Pathfinder User Manual

1.1. Introduction

Pathfinder is an agent-based egress and human movement simulator. It provides a graphical user interface for simulation design and execution as well as 2D and 3D visualization tools for results analysis.

1.2. Download and Install

You can download the current version, sign up for a free trial, and purchase the software from the Pathfinder Support Page. This page also provides instructions for installation and activation. Troubleshooting info can be found on the Pathfinder FAQs page. There is no functional difference between the trial version of Pathfinder and the full version, the only limitation is the trial license duration.

When installing Pathfinder, the installer will either upgrade an existing version or install Pathfinder to a new location, this behavior is based on the version. In the case of minor updates (e.g. upgrading from Pathfinder 2020.1 to Pathfinder 2020.3), the installer will remove the older version and replace it with the new version. When installing a major update (e.g. Pathfinder 2019 to Pathfinder 2020), the older version will not be modified and the newer version will be installed to a different folder.

Administrator privileges are required to install Pathfinder. This is necessary because the installer adds processes to the operating system for license management.

Pathfinder will regularly check for and notify the user of available updates to the software when configured to do so. By default, Pathfinder will check for updates on startup and display the relevant information in the Check For Updates dialog when one is available.

Users can also access this dialog by navigating to Help→Check For Updates

The dialog can be disabled on startup by unchecking Check for newer version on startup. Users can also elect to skip the current update by clicking the Skip Update button, which will prevent update notifications until a new version is released beyond the latest version.

1.3. Graphical User Interface

Pathfinder includes a graphical user interface that is used primarily to create and run simulation models. A screenshot of this user interface is shown in Figure 2. This screenshot displays a model of the Theater de Vest in Alkmaar, Netherlands. The model was created by Van Hooft Adviesburo. For clarity, the image shows only one of the DXF files used to create the geometry. The model includes 2177 occupants.

Pathfinder also includes a second program designed specifically for high-performance visualization of 3D time history. The 3D Results program is shown in Figure 3. In this image, occupants are gathering at a refuge area before proceeding to elevators. Transparency has been used to help view occupants on the refuge floor.

In addition to 3D visualization, Pathfinder also provides output in the form of 2D time history plots of CSV (comma separated values) out files and a text summary of room clearing times and doorway flow rates. An example time history plot can be seen in Figure 4. This plot shows the number of occupants in the refuge area and the total number of occupants in the building.

1.4. Model Representation

The movement environment is a 3D triangulated mesh (Figure 5), designed to match the real dimensions of a building model. This movement mesh can be entered manually or automatically based on imported data (e.g. FDS geometry).

Walls and other impassable areas are represented as gaps in the navigation mesh. These objects are not actually passed along to the simulator, but are represented implicitly because occupants cannot move in places where no navigation mesh has been created.

Doors are represented as special navigation mesh edges. In all simulations, doors provide a mechanism for joining rooms and tracking occupant flow. Depending on the specific selection of simulation options, doors may also be used to explicitly control occupant flow.

Stairways are also represented as special navigation mesh edges and triangles. Occupant movement speed is reduced to a factor of their level travel speed based on the incline of the stairway. Each stairway implicitly defines two doors. These doors function just like any other door in the simulator but are controlled via the stairway editor in the user interface to ensure that no geometric errors result from a mismatch between stairways and the connecting doors.

Elevators are called to a floor when occupants arrive at the elevator door. The elevator model includes capacity, pick-up and discharge floors, and the ability to group elevators in banks.

Each occupant is defined by position, a profile that specifies size, speed, etc., and a behavior that defines goals for the occupant. The behavior allows scripting so that, for example, an occupant may wait at a location for a specified time and then proceed to an elevator. The occupant is represented as an upright cylinder on the movement mesh and movement uses an agent-based technique called inverse steering. Each occupant calculates movements independently.

1.5. Simulation Modes

Pathfinder supports two movement simulation modes. In "Steering" mode, occupants use a steering system to move and interact with others. This mode tries to emulate human behavior and movement as much as possible. SFPE mode uses a set of assumptions and hand-calculations as defined in the Engineering Guide to Human Behavior in Fire (SFPE 2019). In SFPE mode, occupants make no attempt to avoid one another and can interpenetrate, but doors impose a flow limit and velocity is controlled by density. You can freely switch between the two modes within the Pathfinder user interface and compare answers.

More information about both modes is provided in the Pathfinder Technical Reference (Pathfinder Technical Reference, n.d.).

1.6. System Requirements

System requirements depend on the type of model being analyzed. To illustrate this, two different models (Table 1) were evaluated using a laptop running 64-bit Windows 8 Pro with an Intel Core i7 2.60 GHz processor, 8 GB of RAM, and NVIDIA NVS 5200M graphics card. The first model (Figure 6) had a single room with 50,000 occupants and did not include any imported geometry. The second model (Figure 7) imported a relatively complex Revit model to create the Pathfinder model and had 3,000 people.

The key parameters are the number of people in the model and the model complexity, measured by the number of navigation mesh triangles used in the Pathfinder solution and the number of imported Revit primitives (triangles). The simple model had only 4 triangles, with the consequence that the movement calculation of the path for each person is simple and that display performance is related to the drawing of people. The Revit model had 21,480 triangles for the navigation mesh but over 1,300,000 triangles for the Revit geometry.

The model with 50,000 people (Figure 6) solved in about 18 minutes, while the Revit model with 3,000 people (Figure 7) took about 5 minutes. The graphical display performance for the model with 50,000 people was responsive at 15 frames/sec, while the Revit model with the imported geometry displayed was slow at 5 frames/sec. When only the Pathfinder navigation mesh was displayed, the Revit model was responsive.

The minimum requirements to run Pathfinder include:

For a balanced performance we recommend:

Revit models place a premium on graphics capability. We have found that mid-cost gaming graphics cards (GeForce GTX 570 / Radeon HD 7870 or equivalent) allow us to display relative large Revit models with good performance. Benchmarking sites that we find useful to compare CPU and graphics card performance can be found at: http://www.cpubenchmark.net/ and http://www.videocardbenchmark.net/.

1.7. Configuration Files

Pathfinder stores data related to user preferences in a file called Pathfinder.props. By default, this file can be found in one of:

%APPDATA%\Pathfinder\Pathfinder.props
%PROGRAMDATA%\Pathfinder\Pathfinder.props

If at least one of these files exists, Pathfinder will load the user preferences. If both files exist, Pathfinder will load user preferences from both files, giving preference to the file located in the APPDATA folder. This way the preference file located in the PROGRAMDATA folder can be shared among multiple machines, and the file located in the APPDATA folder on each machine overrides the shared settings.

The PROPS file is stored in a plaintext format, and can be viewed or edited with any conventional text editor. While it is not recommended to edit the file directly, some troubleshooting techniques may involve deleting the PROPS file so that a new one can be created from scratch by Pathfinder.

1.8. Contact Us

Thunderhead Engineering
403 Poyntz Avenue, Suite B
Manhattan, KS 66502-6081
USA

Sales Information: sales@thunderheadeng.com
Product Support: support@thunderheadeng.com
Phone and Fax: +1.785.770.8511

2.1. Navigation View

The Navigation View helps you quickly find objects and data that are not always easily accessible from the 3D and 2D views.

The Navigation View is arranged in the following groups:

The buttons directly above the Navigation View perform the following actions:

The Floor selection box above the Navigation View panel (see the top of Figure 8) can be used to manage floors. Any time a room, stair, ramp, or door is created it is added to a floor group matching the current selection in the Floor box. Changing the selection in the Floor box will cause the newly selected floor to be shown and all other floors to be hidden. Also, the Z property for all drawing tools will automatically default to the height of the floor currently selected in the Floor box. The visibility of any object or group of objects can always be manually set using the right-click context menu. This technique is useful if you want to show two floors at the same time (e.g. when creating a stairway).

2.2. 3D and 2D Views

The 3D and 2D views as shown in Figure 9 are the main views in which drawing is performed in Pathfinder. Both views contain tools to draw egress geometry and navigate in a model. The main difference between the two views is that the 3D view allows the model to be viewed from any direction, whereas the 2D view only allows viewing from one, orthographic direction. In addition, the 3D view contains no snap grid, whereas the 2D view does. The 3D view is entered by selecting the perspective camera, , and the 2D view is entered by selecting one of the orthographic cameras, , , or .

At the top of the view is several buttons that show different camera modes, display options, and navigation modes. The panel under this is known as the Property Panel and is a selection context-sensitive panel. If a drawing tool is selected, it will show properties that can used to help draw. If no drawing tool is selected, and an object or several objects are selected, this panel will show the properties relevant to the selection. The panel of buttons on the left shows move/copy and drawing tools. The small panel at the bottom displays messages relevant to the current tool.

2.3. View Options

Pathfinder provides a variety of view options for displaying both navigation geometry and imported geometry that can also aid with drawing. This includes options for rendering geometry, displaying agents, coloring rooms, and setting the transparency of rooms.

2.3.1. Render Options

In the toolbar above the properties window in the 2D and 3D views, there are a number of buttons as shown in Figure 10 that control how geometry is rendered.

From left to right, the buttons are:

Wireframe Rendering

Displays imported 3D geometry as wireframe only. This option is mutually exclusive with the solid rendering option. It is useful for drawing doors in the 2D view when 3D geometry has been imported.

Solid Rendering

Displays imported 3D geometry filled in. This is selected by default.

Show Materials

Shows materials applied to the faces of imported 3D geometry. This is selected by default.

Show Object Outlines

Shows the outlines of 3D imported geometry. This is similar to showing the wireframe and solid versions at the same time.

Smooth Lighting

Uses a more realistic shading model to show all geometry. This may be a little slower to render on older graphics cards.

Show Navigation Geometry

This toggles the visibility of all the navigation geometry. It does not affect anything else (including imported geometry and occupants).

Show Imported Geometry

This toggles the visibility of all imported 3D geometry.

Show Occupants

This toggles the visibility of occupants.

Show Behaviors

This toggles the visibility of behavior objects, such as waypoints.

Show Occupant Sources

This toggles the visibility of occupant sources.

Show Measurement Regions

This toggles the visibility of measurement regions.

Show View Objects

This toggles the visibility of view objects.

Show Attractors

Toggles the visibility of attractor objects.

2.4. Model Organization with Groups

The main method of organization in Pathfinder is to use groups. In every model there are already some implicit groups that cannot be modified, including Views, Imported Geometry, Profiles, Vehicle Shapes, Assisted Evacuation Teams, Behaviors, Occupant Sources, Occupants, Movement Groups, Movement Group Templates, Elevators, Measurement Regions, and Floors as shown in Figure 11. Sub-groups can be created to further organize the model as discussed in the following sections.

2.5. Keyboard Shortcuts

By default, Pathfinder uses a variety of keyboard shortcuts that are standard to Windows and Java applications. To accelerate model creation, shortcuts can be added or changed to in a variety of ways.

Some keyboard shortcuts are used by Java UI components. If a shortcut does not result in the expected behavior, it may be in direct conflict with a preexisting Java shortcut. It is best practice to avoid these conflicts (Default Swing key bindings (IBM n.d.)).

2.5.1. Keyboard Shortcut Editor

The Keyboard Shortcut Editor Window can be found in the File→Preferences dialog and clicking Edit Actions and tools can are bound to a combination of modifier keys (ALT, CTRL, SHIFT, etc.) and other key presses.

The dialog is split into sections similar to those used in the Pathfinder toolbar menus. There are additional tabs for shortcuts related to tool activation, object selection, and context sensitive actions.

To change a shortcut, click on cell in the Key Press column and a window launches (Figure 13) with four different options.

Type an input

Input the desired keybinding to map it to the action.

Clear

Remove the current keybinding from the action.

Reset

Assign the default keybinding to the action.

Cancel

Exit the editor window without making any changes.

2.6. Object Sets and Discrete Distributions

There are times when a set of objects might need to be selected or a distribution of discrete items specified. Pathfinder provides two dialogs that can be used to do so.

2.6.1. Object Sets

When specifying a set of items, such as the doors an occupant is allowed to use, the Figure 14 is shown.

The list in this dialog shows the items in the model that can be chosen. Click the checkbox next to the item in the list to select the item. Alternately, click the checkbox in the header of this list to select or deselect all items currently displayed in the list.

Click OK to commit the selected items.

Sometimes, the list of items might be quite long, making it difficult to quicky find the desired items. There are several ways to limit the displayed items, however. At the top of the dialog is a search field. Typing in this field will limit the list of items to only those that partially contain the entered text. To match the name of an object exactly, surround the text with quotes. For example "Door01" will show only the doors that have exactly the name, Door01. This search field also allows wildcards including the following:

?

Matches any single character

*

Matches any number of characters

For example, typing Door?1 would find objects with the following names: Door01, Door51a, Exit Door91 (south), etc. It would not, however, find the following: Door001, Door9221, etc. Typing Door*1, however, would find those.

Another way to limit the displayed item is to check the box next to Show only selected rows. This will only show items that have already been selected. By default, when the Set Chooser dialog opens, if there are selected items in a long list, Show only selected rows will be automatically selected so it’s easy to see the current selection.

The following additional options are also available:

Clear

Clicking this button will clear the selection, including both displayed and hidden rows.

Show group labels

If checked, the group labels for each item is shown in the list. For example, "Door01" might become "Floor 0.0 m→Door01".

2.6.2. Discrete Distributions

Pathfinder also allows discrete distributions of objects in certains cases. For example, the Change Behavior action allows occupants to change their behavior by choosing a random behavior from a discrete distribution. Occupants might have a 30% chance of choosing Behavior01 and 70% chance of choosing Behavior02. The Figure 15 allows these distributions to be specified.

In this dialog, the probability of choosing a value can be entered into the first column. The second column shows the name of each available item. The sum of the values in first column must add to 100%.

As in the Set Chooser dialog described above, the displayed items can be filtered either by typing text into the search field at the top of the dialog or by clicking Display only non-zero rows, which only shows rows that have non-zero probabilities. In addition, Show group labels can be checked to show the names of the groups next to the item names in the list, such as "BehaviorGroup01→Behavior01".

The distribution dialog has some additional actions that can be used to clear values or distribute probabilities evenly among several items.

To set the probability of multiple items to 0.0%, click the Clear button and choose from one of the following options in the popup menu:

Clear selected rows

Clears the values for all highlighted rows.

Clear displayed rows

Clears the values for all rows currently in the list but not hidden rows.

Clear all rows

Clears the values for all rows, including hidden rows that do not match the current search field.

To distribute probability evenly across multiple rows, click the Distribute Evenly button and choose one of the following option in the popup menu:

Distribute remaining X% to selected rows

This is only available if the current total distribution is less than 100%. It will distribute all remaining values to those currently highlighted in the list. For instance, if the current total distribution is 85%, and there are 3 highlighted items in the list, this action will add (100 - 85)/3 = 5% to each selected item’s current probability, ensuring that the end total distribution is 100%.

Distribute remaining X% to displayed rows

Distributes the remaining values evenly across all displayed rows.

Distribute 100% to selected rows

Clears all rows (including hidden rows) and then evenly distributes 100% across only those that are highlighted.

Distribute 100% to displayed rows

Clears all rows (including hidden rows) and then evenly distributes 100% across those currently displayed in the list.

Distribute 100% to all rows

Clears all rows (including hidden rows) and then evenly distributes 100% across all rows, including hidden rows.

3.1. Floors

Floors are the primary method of organization in Pathfinder. At their most basic level, they are simply groups in which rooms, doors, stairs, ramps, and exits can be placed, but they also control the drawing plane for most tools and filtering of imported geometry.

In every Pathfinder model, at least one floor must exist, and at any given time, there is one active floor. Whenever any navigation object is drawn, it will either be placed in the active floor or a subgroup of the active floor.

By default when a new model is started, there is one floor at Z=0, and additional floors are either created automatically depending on where the geometry is drawn or manually created. In addition, new navigation components are automatically sorted into the appropriate floor when drawn.

3.1.1. Automatically Creating Floors

When nothing is selected in the model, the Floor Creation panel is shown, as in Figure 16. This panel controls the automatic creation of floors and automatic sorting of new objects into floors.

Auto sort egress components

If this is checked, navigation components are automatically sorted into the appropriate floor when created or modified; if this is unchecked, new navigation components are placed in the group specified under New Egress Components and remain in this group until manually moved.

Automatically create floors

If this is checked, floors are automatically created as navigation components are created and modified.

Floor height

This specifies the height at which new floors are automatically created. If a navigation component is created or moved to a location that is at least this distance from the previous floor, a new floor will be created at a multiple of this distance from the previous floor.

Group

If Auto sort egress components is unchecked, this drop-down specifies the group/floor for new navigation components.

The following scenario demonstrates how objects are organized when auto-sort and auto-floor-creation are enabled (organization of the model is shown in Figure 17):

1. A new model is created. The floor height is left at the default of 3 m.
2. "Room00" is drawn at Z=0 m, and is auto-placed in "Floor 0.0 m".
3. "Room01" is drawn at Z=1.5 m, and is auto-placed in "Floor 0.0 m".
4. "Stair01" is drawn connecting "Room00" to "Room01" and is auto-placed in "Floor 0.0 m".
5. "Room02" is drawn at Z=-1.5 m. A new floor, "Floor -3.0 m" is auto-created, and "Room02" is auto-placed in it.
6. "Stair02" is drawn connecting "Room02" and "Room00" and is auto-placed in "Floor -3.0 m".
7. "Room03" is drawn at Z=7.5 m.
8. A new floor, "Floor 6.0 m" is auto-created, and "Room03" is auto-placed in it.

In this example, only rooms and stairs were created. The floors were automatically created and the rooms and stairs were automatically sorted into the appropriate ones.

3.1.1.1. Using Auto-sort with an Existing Model

Automatic floors can be created and components sorted into the floors by performing the following:

1. Open the model.
2. Clear the selection so that the Floor Creation panel is visible (Figure 16).
3. Ensure that the desired creation/sorting options are enabled and that the correct floor height for the model is set.
4. Select all the components that should be auto-sorted (if everything should be sorted, select the Floors top node).
5. Right-click the selection, and from the shortcut menu, click Sort into Floors.
6. The appropriate floors will be created and all selected items will be sorted into the appropriate floors.

3.1.2. Manually creating floors

Floors can also be created manually at any time.

1. Click on the floor drop-down box above the Navigation View, and select <Add New> as shown in Figure 18. A dialog will open asking for the floor location.
2. Enter the Z plane location (Figure 19) or click on a snap point in the 3D or 2D view and click okay. This Z plane will be used to update the drawing tools' working Z location when this floor is made active.

There are two other options in this dialog:

Set as active floor

The floor is set to be the active floor in the model after being created.

Resort existing egress components into new floor

All existing components that belong in the new floor will be moved to it.

By default, the name of the floor is Floor \(x\) where \(x\) is the working plane of the floor.

Manually Adding a New Floor

3.1.5. Floor Properties

To edit a floor’s properties, first select the desired floor. The property panel as shown in Figure 20 will appear, showing the floor’s name, its Working Z location, and the Z clipping planes (Z Min Filter and Z Max Filter) for imported 3D geometry.

It also shows some statistics of the floor including the total area of the floor (Area), number of people on the floor (Pers) and density of people. Refuge Area and Speed Modifier are discussed in Section Room properties.

Working Z

Controls the plane on which new rooms and wall obstructions are drawn.

Z Min and Max Filters

Control the clipping planes of imported 3D geometry when the floor is visible. Anything below Z Min and above Z Max is clipped.

Z Min Filter

Can be a Z plane location or can have the special value, CURR_FLOOR. If it is CURR_FLOOR, then the clipping plane is set to the working Z location if there are any floors below this floor or \(-\infty\) if there are no floors below.

Z Max Filter

Can be a Z plane location or can have the special value, NEXT_FLOOR. If it is NEXT_FLOOR, then the Z plane is set to the working Z plane of the next higher floor if one exists, or \(+\infty\) if there are no higher floors.

3.2. Rooms

Rooms are open space on which occupants can freely travel. Each room is bounded on all sides by walls. Rooms can be drawn so that they touch each other, but an occupant can only travel between them if they are connected by a door. Only one room can occupy a given space at any time, so if one room is drawn overlapping another, the overlapping area will be subtracted from the old room and given to the new. Rooms can also be merged into one, separated into constituent parts, and have internal, thin boundaries drawn in them. These features are discussed in the following sections.

3.2.1. Adding New Rooms

Pathfinder provides two tools for adding new room geometry:

Polygonal Room Tool

The Polygonal Room tool allows for the creation of complex shapes with any number of vertices (Figure 21).

Left-click anywhere in the model to set the first point, and continue left clicking to add more points to the polygon. When at least three points are defined, right-clicking will close the polygon and complete the shape.

Alternatively, X,Y coordinates can be entered from the keyboard with the Add Point and Close Polygon buttons from the property panel.

Rectangular Room Tool

The Rectangular Room tool creates simple rectangular geometry by left-clicking two points in the model (Figure 22).

The rectangular area can also be created by entering coordinates for two points in the property panel and clicking Create.

In addition to creating new areas, both of these tools can be used on existing geometry to create negative areas. Creating new geometry over existing areas removes any interfering portion from those areas. The newly created geometry can then be deleted, leaving the negative space behind. This is discussed further in the section, Arbitrarily-shaped obstructions (desks, tables, etc.).

3.2.2. Drawing Plane

Each room tool draws on a particular Z plane that is specified in the property panel for the tool as shown in Figure 23.

The Z plane can be specified either manually by typing the location into the Z Plane field or by picking the location from the 2D View or 3D View as follows:

1. Select one of the room drawing tools.
2. In the tool property panel, click Pick Z from Scene. This will clear the tool property panel while waiting for the user to click a location.
3. Click a point in either the 3D View or a 2D View. The tool property panel will return for the selected drawing tool, and the Z Plane field will be filled with the Z coordinate of the clicked location.

3.2.3. Splitting Rooms

Rooms can be split into two or more pieces using the Thin Wall tool. To do this, specify the two points such that they are on the outermost boundary of the room to be divided. The original geometry will be divided into two or more new rooms with that line as the boundary between them as shown in Figure 25.

Dividing a Room

3.2.4. Separating and Merging Rooms

In addition to dividing rooms, Pathfinder has two additional means to aid in creating more complex room geometry.

Merge

The Merge command is used to join two or more rooms that share boundaries into one room. They can also be merged with stairs and ramps, but the stairs and ramps will be converted into rooms and will lose their stair/ramp properties.

To Merge rooms:

1. Select the neighboring rooms
2. Select Merge from either the Model menu or the right-click menu (Figure 26)

Merging rooms

Separate

The Separate command breaks a room into its constituent parts along any negative space that divides it (Figure 29).

To Separate a room:

1. Select the room to be separated
2. Select Separate from either the Model menu or the right-click menu (Figure 28).

Separating a room

3.2.5. Room Properties

To view and edit room properties, select a room. Its properties will be displayed in the property panel as shown in Figure 30.

Name

An identifying name for room.

Visible

Whether the room is currently visible. Uncheck to hide the room.

Color

The color of the room. If unchecked, a default room color is used.

Opacity

The opacity of the room. Making this value less than 100% will cause objects behind the room to become visible.

X, Y, and Z Bounds

The geometric bounds of the room.

Area

The geometric area of the room.

Pers

The number of occupants currently placed in the room.

Density

The number of occupants/area

Refuge Area

Marks the room as a Refuge area, which can then be specified in a list of rooms for the Goto Refuge Rooms action as discussed in Section 5.3.3. When this option is selected, occupants will be tagged as "safe" whenever they are in the room. The "safe" times are reported in the Occupants Summary (Section 14.7) and Occupant History (Section 14.8) output files.

Speed Modifier

A time-variable factor that affects the speed of each occupant who travels in the room. When occupants travel in the room, their maximum speed is multiplied by this factor. This could be used, for instance, to represent the effect of smoke on occupant speeds. By default, the modifier is 1.0 throughout the simulation. To change this, click the link. The Edit Speed Modifier dialog appears as shown in Figure 31. In this figure, for instance, the room initially leaves occupant speeds unmodified, but over the first 40 seconds ramps occupant speeds down to 25% of their maximum values.

Capacity

A maximum capacity of the room, which can be specified using an occupant count or a density. Specifying room capacity is optional. If at any time during the simulation the room capacity reaches the limit, no occupants will enter the room until the room capacity decreases below the limit.

Accepted Profiles

A list of occupant profiles for which the occupants can enter this room (see Section 2.6.1 for help using this dialog). By default, all occupant profiles are accepted.

3.2.6. Preventing Room-Crossing

In some cases, such as modeling seating rows or shops in a mall, it may be desirable to only allow occupants to exit the room and not cross through it. This can be accomplished by making all the doors connected to the room one-way (see Doors) and ensuring that their directions point out of the room. Pathfinder provides a tool to make this easy. Instead of individually setting the one-way status of all the connecting doors, perform the following:

1. Select the room(s) that should not be crossable.
2. Right-click one of the rooms, and from the menu select Make Doors One-way. A dialog will appear as in Figure 32.
3. From this dialog, choose whether occupants can only Enter or Exit the room. If any of the room’s doors were already marked as one-way, another option will be provided to overwrite the one-way status of those doors.
4. Click OK in this dialog to make the doors one-way.

Pathfinder will automatically calculate the correct directions for the doors to make the rooms exit-only or enter-only.

3.3. Obstructions/Holes

In Pathfinder, obstructions are modeled as holes in the navigation geometry. Holes can be created with an arbitrary polygonal shape or as thick walls.

3.3.1. Arbitrarily-Shaped Obstructions

To model an obstruction (e.g. an office desk or other standing obstacle) within a room, the subtractive property of rooms is used. This means that the room containing the obstruction must already exist.

To create the obstruction:

1. Select the Add a Polygonal Room tool or the Add a Rectangular Room tool and draw the shape and location of the obstructed area. This will subtract the area from the old room and create a new room.
2. Next, delete the new room. A hole is left in the old room in the shape of the obstruction. This process is shown in Creating an obstruction.

Creating an obstruction

3.3.2. Thin Walls

Thin, internal walls or boundaries can be added to rooms with the Thin Wall tool .

To use this tool, click two points in the model as shown in Figure 37. Pathfinder will attempt to connect these two points with an internal boundary edge.

3.3.3. Thick Walls

The wall tool is used to make rectangular obstructions in existing geometry (Figure 38).

To make a thick wall:

1. Click on the wall tool.
2. Enter the desired wall width in the property panel.
3. Click or click-drag the two points the wall is to pass through. Holding the shift key will switch between alignment left and right of the defining line.

3.4. Doors

In Pathfinder, occupants cannot pass between two rooms unless they are joined by a door. Doors provide useful flow measurements in simulation results. Also, in the SFPE mode doors act as the primary flow control mechanism. You can add doors using the Add a New Door tool.

When adding doors, different parameters provide hints to Pathfinder for finding a valid door as shown in Figure 39.

3.4.1. Thin Doors

Thin doors can be used to connect two rooms that touch one another as shown in Figure 40. A door is needed in this example to allow occupants to travel from one room to the other.

To create a door in this manner:

1. Select the door tool .
2. Then use one of the following three methods:
   1. Manual Entry: Enter the coordinates of the door in the property panel. If the coordinates specify a valid door location, the Create Door button will enable. Click this button, and a door no larger than Max Width will be created. For thin doors, Max Depth will be ignored.
   2. Single Click: Move the cursor over the desired door location in the 3D or 2D view. A preview door will be displayed if the cursor is on a valid edge. The door displayed will lie either to the left or right of the hover point relative to the boundary edge, depending on whether Max Width is positive or negative. Single click to place the door. The previewed door will then be added to the model.
   3. Click-drag: Move the cursor over the location of one end point of the door, and click drag along the same edge. While dragging, a preview door will be displayed from the first to the second point. When the mouse is released, a door is created along the edge between the two specified points. Creating a door in this manner ignores all the properties in the tool panel.
3. The created door will appear as a thin, orange line in the 3D and 2D views as shown in Figure 41.

3.4.2. Thick Doors

Thick doors are often useful in realistic models, especially when CAD geometry has been imported. In real scenarios, rooms will not touch each other by infinitely thin walls as shown in Figure 42.

To create a thick door to connect these rooms:

1. Select the door tool
2. Use one of the following three methods:
   1. Manual Entry: Make sure Max Depth is greater than or equal to the distance between the edges the door will lie between. Enter a point on one of the edges in the property panel. If the coordinates specify a valid door location, the Create Door button will enable. Click this button, and a door no larger than Max Width will be created.
   2. Single Click: Make sure Max Depth is greater than or equal to the distance between the edges the door will lie between. Then move the cursor over the desired door location in the 3D or 2D view. A preview door will be displayed extending between the rooms if the cursor is on a valid edge. The door displayed will lie either to the left or right of the hover point relative to the boundary edge, depending on whether Max Width is positive or negative. Single click to place the door.
   3. Click-drag: Move the cursor over the edge of one of the rooms, and click drag along the corresponding edge on the second room. While dragging, a preview door will be displayed connecting the two edges. When the mouse is released, a door is created between the edges of the two rooms, where the diagonal of the rectangular door connects the two specified points. Creating a door in this manner ignores all the properties in the tool panel.
3. The created door will appear as an orange rectangle in the 3D and 2D views as shown in Figure 43.

When simulating, thick doors have a special representation: the area of the door will be partitioned in two, and each half is attached to its touching room. A thin door is placed in the middle of the area to represent the thick door.

3.4.3. Door Properties

To edit a door’s properties, select the door. Its properties will appear in the property panel as shown in Figure 44.

Width

The width of the door. Changing this value will change the width of the door, but the value cannot exceed the length of its room edge.

Flow Rate

Checking this box overrides the default door flow rate setting in the Simulation Parameters Dialog (see Section 13.1). Setting this value controls the maximum occupant flow rate for the door in units of pers/s. This can be used, for instance, when a particular door has been measured to flow at a specific rate and that rate must be reproduced. A value of 0.9 pers/s, for instance, would mean that one occupant can go through the door every 1.1 seconds (1/0.9).

State

Indicates the timed opening, closing, and changing the one-way direction of the door, see Section 3.4.3.1. A One-way door is one through which occupants can only travel in one direction.

Wait Time

Amount of time for which each occupant must wait at the door before walking through it. This can be used to simulate turnstyles or doors with access keys. The specific wait time for each occupant will be drawn at random from a predefined continuous or discrete distribution.

Accepted Profiles

A list of occupant profiles for which the occupants can enter this door. By default, all occupant profiles are accepted.

3.4.3.1. Door State

By default, all doors are always open throughout the simulation. To change this, click the link to the right of State.

The Edit Door State dialog will appear as shown in Figure 45. This dialog allows the initial state of the door to be specified as well as additional timed states.

As shown in the figure, for example, the door is initially open, closes at t=10 s, opens in +X direction at t=20 s, and then opens in both directions again at t=30 s.

Even though a door can only be travelled through in two possible directions, the drop-down box allows +X, -X, +Y, and -Y. When one of these directions is chosen, the actual direction Pathfinder chooses is the closest along the door’s normal.

3.5. Stairs

Stairs in Pathfinder are represented by one straight-run of steps. They can be created with two tools. One tool allows creation of stairs between two semi-parallel boundaries of rooms, and the other allows creation of stairs that extend from one room boundary until a criterion is met, such as number of steps, height of stairs, etc., or until another room is reached.

One requirement of all stairs for successful simulation is that each end of the stairs must connect to boundary edges of the rooms, meaning that there must be empty space at the top of the stairway and empty space below the bottom. See Stair geometry requirements for an illustration of this issue. The size of the gap must be greater than or equal to the radius of the largest occupant to travel on the stairs.

Stair geometry requirements

3.5.1. Stairs Between Edges

One way to create stairs is to draw them between two pre-existing rooms. Stairs of this type will match the ends of the stairs exactly to the edges that they were drawn between, which means that the tread rise and run may or may not match the actual slope of the stairs. In Pathfinder, the speed on stairs is determined by the specified tread and run. The geometric slope of stairs is for display only and not used to calculate the speeds.

To create stairs between edges:

1. Ensure that both the connecting rooms are visible. If the rooms are on different floors, at least one room will have to be manually set visible, which can be done through the right-click menu in the Navigation View.
2. Select the two-point stair tool, . The property panel will display the stair creation properties as shown in Figure 48.
3. The stairs can now be created in one of the three following ways:
   1. Manual Entry: Set the desired stair width, and for each edge on which the stairs should be created, enter a point. If the points are valid, a preview stair will be shown in the 2D or 3D view and the Create button will enable. Click Create to add the stairs.
   2. Two-click: Set the desired stair width. Move the cursor over the first edge, and a preview line similar to a thin door will appear previewing the top or bottom of the stairs. Single-click to set the point. (Figure 49) Now move the cursor over the second edge. Now a preview of the stairs will appear connecting the first edge to the second. Single-click on the second edge to create the stairs (Figure 50).
   3. Two-click with drag: Click-drag on the first edge to specify both the starting point and width of the stairs. Release the mouse and then single-click on the second edge to place the stairs.

To change the display, you may:

1. Measure the total vertical rise of the stair.
2. Set the tread rise to total rise/desired step count

Drawing stairs with the two-point stair tool

3.5.2. Stairs Extending from One Edge

Another way to create stairs is to have them extend from an edge and exactly match the specified tread rise and run. They will stop when they meet a specified criterion or reach another room.

The property panel for the one-click stair tool, as shown in Figure 51, provides four ways to terminate the stairs:

Step count

The stair will have this many steps.

Total rise

The stair will be this tall in the Z direction.

Total run

The stair will be this length in the XY plane.

Total length

The hypotenuse of the stair will be this length.

To create stairs in this manner:

1. Select the one-point stair tool, . The property panel will show.
2. If the tread rise is positive, the stairs will extend up from the starting edge, and if it is negative, the stairs will go down. Similarly, if the tread run is positive, the stairs will extend away from the room, and if it is negative, the stairs will extend in toward the room. Another way to change these values is to hold CTRL on the keyboard to make the tread rise negative and hold SHIFT to make the run negative.
3. Now the stairs can be created in one of the three following ways:
   1. Manual Entry: Set the desired stair width, tread rise, tread run, and termination criterion. Specify the starting point on the desired edge. If the location is valid, a preview stair will be shown, and the Create button will enable. Click Create to add the stairs.
   2. Single-click: Set the desired stair width, tread rise, tread run, and termination criterion. Move the cursor over the starting point on the room’s boundary. A preview stair will be displayed. Single click to place the stairs.
   3. Click-drag: Set the desired tread rise, tread run, and termination criterion. Now click-drag along the room’s boundary to specify both the location and the width of the stairs.
4. Release the mouse to create the stairs.

After creating stairs in this manner, the Z location of the next floor or room will have to match the top of the stairs exactly for the next room to connect properly to the stairs. This can be done by clicking the top of the stairs in the 3D or 2D view when choosing the Z location for either the floor or next room.

After creating a one-click stair, you can only modify the stair by clicking the handles and dragging to existing geometry.

3.5.3. Stair Properties

Stairs have a number of properties that control their geometry and behavior of occupants that travel on them. When a stair is selected, these properties can be seen in the stair’s property panel as shown in Figure 53.

Riser and Tread

Together, these parameters control the speed at which occupants can travel on the stairs during simulation. The default speed on stairs uses the SFPE speed modifiers, see (Pathfinder Technical Reference, n.d.). While the one-point stair tool uses the tread rise and run to create the initial shape of the stair, these properties can later be changed without affecting the stair shape.

Length

The total length of the stair from the bottom to top edge. This is the same as the hypotenuse formed by the total stair rise and total stair run.

Width

The width of the stair.

Top Door and Bottom Door

Clicking these links show the dialog in Figure 54. Here, properties of each implicit door can be edited independently of the other door, including Width, Flow Rate, and State. For more information on these properties, see Section 3.4.3.

One-way

Indicates whether the stair should only allow occupants to travel in one direction and if so, which direction.

Speed Modifier

A time-variable factor that affects the speed of occupants who travels on the stair. This acts the same as the Speed Modifier property for rooms (see Section 3.2.5).

Capacity

A maximum capacity of the stair, which can be specified using an occupant count or a density. This acts the same as the Capacity property for rooms (see Section 3.2.5).

Additional Info

Clicking this link shows additional information about the stair, such as its geometric bounding box, area, and number of occupants.

Accepted Profiles

A list of occupant profiles for which the occupants can enter this stair. By default, all occupant profiles are accepted.

3.6. Ramps

Ramps are nearly identical to stairs in how they are created and represented. Like stairs, they have two implicit doors at either end and always take the shape of a rectangular piece of geometry.

They also have very similar creation tools: the two-point ramp tool , and the one-point ramp tool . The key difference between ramps and stairs is that ramps do not affect the speed at which occupants travel by default.

3.7. Escalators

Pathfinder provides some limited support for escalators. They are essentially stairs with slightly modified properties.

To create an escalator, perform the following:

In the results view, escalators do not appear differently than stairs.

By default, occupants do not walk on moving walkways or escalators, and they will not stand on any specific side. This can be changed by modifying the occupant’s profile and selecting their Escalator Preference (see Section 5.1). If an occupant is walking, the escalator’s speed constant will be added to the occupant’s current speed on the escalator.

3.8. Moving Walkways

Pathfinder also provides limited support for moving walkways. This is similar to creating escalators, but instead of setting a speed constant on an existing stair, the speed constant is set on a Ramp instead, which can be made flat like a walkway.

3.9. Elevators

Pathfinder supports elevators in egress-mode operation, which is based on current thinking described in Using Elevators In Fires (Bukowski and Li 2010).

The basic operation of elevators in evacuations can be summarized as follows:

3.9.1. Creating Elevators

Elevators can be made after creating the rest of the model.

Perform the following steps to create the elevator (refer to Figure 18):

1. Draw a room that defines the shape of the elevator, preferably on the discharge floor, see Figure 56.
2. Draw all doors on the boundary of the base room, see Figure 57. Occupants will use these doors on every floor to enter and exit the elevator.
3. Right-click the base room, and from the right-click menu, select Create Elevator, see Figure 58. This will show the New Elevator dialog as shown in Figure 59.
4. In the New Elevator dialog, enter all parameters for the elevator:

   Name

   The name of the elevator.

   Nominal Load

   The number of people in a full load (estimated). Please read the Nominal Load section below for details.

   Elevator Geometry

   The base room that defines the elevator shape. This defaults to the room that was originally selected.

   Travel Direction

   A vector defining the direction the elevator can travel. This vector will automatically be normalized. The elevator can travel negatively against this vector.

   Elevator Bounds

   This defines the bottom-most and top-most floors the elevator can connect to.

   Elevator Timing

   This defines a basic timing model used to calculate the travel times for the elevator to travel from the discharge floor to each pickup floor.

   Acceleration (Elevator Timing) [optional]

   The acceleration of the elevator.

   Max Velocity (Elevator Timing)

   The maximum velocity that the elevator can accelerate to.

   Open+Close Time (Elevator Timing)

   The sum of the door opening and closing times. Each value will be taken as half of this.

   Call Distance

   The distance away from the elevator door at which an occupant can call the elevator.

   Double-Deck

   Whether the elevator should use two connected decks to transport occupants. Please see the Double-Deck Elevators Section for details.

5. Click OK to create the elevator.

If necessary, Pathfinder will automatically subtract holes in existing geometry to make space for the elevator shaft. It will also delete existing rooms, doors, stairs, and ramps in the elevator shaft. Pathfinder will ask before making any of these changes.

In order for occupants to use elevators, they must either be allowed to use elevators in their Profile under Restricted Components (see Section 5.1.2) or be explicitly told to do so through their behaviors, as discussed in Behaviors. Occupants can be encouraged to prefer elevators to stairs using the Elevator Wait Time Profile parameter (see Section 5.1.4).

3.9.2. Elevator Representation

Once an elevator is created, it will appear in the model as a series of "rooms" and doors connected by a transparent elevator shaft as shown in Figure 60. There is one room and set of doors for each floor to which the elevator can connect. In the 3D and 2D Views, each room is shaped the same as the base room that created the elevator. In the Navigation View, each room is shown under the elevator rather than the Floors top node, see Figure 61. In addition, each set of doors for the room is shown under the room. By default, each of the rooms is named after the floor on which it connects. If the elevator is disconnected completely from a floor as discussed in Connecting/Disconnecting floors, the room is named "<Disconnected Level>".

3.9.3. Elevator Properties

Once an elevator is created, the elevator’s properties can be edited by first selecting it from the navigation view or by ALT-clicking one of its rooms from the 2D or 3D view. Its properties can be edited in the property panel as shown in Figure 62.

Nominal Load

The number of people in a full elevator load (estimated). Please read Section 3.9.4 below for details.

Open Delay

The minimum amount of time an elevator’s doors will stay open on a pickup floor.

Close Delay

The minimum amount of time the elevator’s doors will stay open after an occupant passes through one of the doors. This can also be thought of as the time someone in the elevator will hold the door open waiting for another occupant to enter. This delay time will reset every time an occupant passes through the doors. If the delay time passes without another occupant passing through the doors or without another occupant appearing in range of the doors or the elevator reaches capacity, the doors will close. The total amount of time for elevator doors to stay open, assuming no other occupants are within sight of the elevator who are heading toward it, can be summarized as: \(t_{\text{open}} = \max\left( \text{delay}_{\text{open}},t_{\text{last}} + \text{delay}_{\text{close}} \right)\)

Discharge Floor

The floor at which occupants will discharge during an evacuation.

Floor Priority

The priority of the floors for pickup. By default this is top-down. This can be changed, however by clicking the text, which will show the Floor Priority dialog as shown in Figure 63. This allows the simulation of a fire floor.

Level Data

Click the Level Data: Edit link to edit timing for each floor. This will open the Elevator Levels dialog as shown in Figure 64.

Delay

The time delay from the start of the simulation for when the elevator can start picking up occupants from a floor. This value does not affect the discharge floor.

Open+Close Time

The total amount of time it takes to open and close the doors for this floor. The door is assumed to open and close at the same speed, so after arrival at a floor the door will open after a delay of half the specified Open+Closed Time. Similarly, after the door closes the elevator will leave the floor after a delay of half the specified Open+Closed Time.

Pickup Time

The time for the elevator to travel from the discharge to the pickup floor.

Discharge Time

The time for the elevator to travel from the pickup to the discharge floor.

Reset

By selecting the Reset option at the bottom of the dialog, an Elevator Timing dialog will open, allowing automated recalculation of the Level Data parameters. The timing options shown are the same as those shown when creating the elevator.

Initial Floor

The floor at which the elevator deck will be located at the beginning of the simulation.

Call Distance

The distance away from the elevator door at which an occupant can call the elevator.

Double-Deck

Whether the elevator should use two connected decks to transport occupants. Please see Section 3.9.7 for details.

3.9.6. Call Sets

By default, each elevator is called individually. Elevators can be grouped into call sets, however, so that when one is called, all elevators in the call set respond and travel to the pickup level.

To create a call set:

1. Create a group in the top Elevators group.
2. Add the desired elevators to the new group.

All elevators in the group will be in the same call set as shown in Figure 65.

3.10. Exits

In Pathfinder, exits are merely thin doors that exist on the boundary of the model. An exit can only have a room on one of its sides.

Exits are created in almost the same way as thin doors as discussed in the section, Thin doors. The only difference is that the door must lie on an edge of a room, and the edge must not be shared between two rooms.

Exit doors are displayed the same as thin doors except that they are green as shown in Figure 66.

4.1. Importing Images

Background images can be imported by clicking Add a Background Image on the Model menu.

The imported image is added to the Imported Geometry → Background Image group in the Navigation View. The image can be edited and deleted from there.

4.2. Importing CAD Files

Pathfinder can import geometry from several CAD formats, including buildingSMART’s IFC format for building information models (BIM), AutoCAD’s DXF (Drawing Exchange Format), DWG, FBX, DAE, and OBJ files.

Depending on which type of file is imported, Pathfinder also provides various tools to generate the navigation mesh elements such as rooms, doors, and stairs, see Section 4.3.

To import one of these files:

All imported elements will be added to the "Imported Geometry" node in the Navigation View. If the CAD file was a DWG or DXF, the grouping structure will include the model level, the layer level, and all entities distributed within the layer. For IFC files, the grouping is determined by the Object Grouping setting as specified above. For other CAD files, the grouping structure will match the node structure in the file. If both lines and faces were included in the import and an entity contained both lines and faces in the CAD file, the entity is split into two in Pathfinder - one with the lines, and one with the faces.

While this option is no longer available, both imported line and face data is now sent directly to the 3D results viewer instead, eliminating the need for a background image.

4.2.1. Imported Objects

When a CAD file is imported, there may be many resulting objects. Depending on the type of imported file, there are various levels of information that may be imported for each resulting object. Each object has a name and always includes some geometric information, such as the 2D curves or 3D faces composing the object. For some files, such as IFC files, there may be even higher-level information such as whether the object is a door and the door’s width. Pathfinder uses this information to generate model elements as described in Working with Imported Data.

Common to all import objects is the ability to set some visual properties, such as color and opacity for each component of the geometry. The imported geometry is sent as-is to 3D Results, resulting in a clean and fast graphical representation of the data.

When an imported object is selected, its property panel appears as shown in Figure 72.

Imported objects have the following properties:

Visible

Whether the object is currently being shown in the 3D or 2D view.

Material

The material applied to the selected faces when the Show Materials option is turned on. Clicking the material button will open the Material Dialog as shown in Figure 85. In this dialog, the material can either be edited or a new material can be applied to the faces by selecting one from the list on the left and clicking the OK button. To remove the reference to the material, select the <No Material> option from the material list.

Color

The color of the selected objects when they have no material or the Show Materials option is turned off.

Opacity

The opacity of the selected objects when they have no material or the Show Materials option is turned off.

X, Y, Z Bounds

The bounds of the object’s geometry.

Object Type

The object’s originating type as specified in the imported file. For IFC files, this is the object’s IFC Entity type, such as IfcRoof. This value cannot be changed.

Import Type

Specifies how the object is to be treated when automatically generating the model as described in Section 4.3.1. Pathfinder chooses the value for this property during import. For more information on how the Import Type is chosen, see the section for each import file type (see Section 4.2.2).

Generate Model from BIM Selection

This action attempts to generate a Pathfinder model from the selected imported objects. For more information, see Section 4.3.1.

4.3. Working with Imported Data

Each type of file that can be imported provides an aid for creating navigation geometry. The different types can be worked with in various ways to create the desired rooms, stairs, and doors.

4.3.1. Generate Model Automatically

The easiest way to create a complete Pathfinder navigation mesh, including rooms, doors, and stairs, is to use the Generate Model from BIM action. This action works best with imported IFC files, but it can work with other CAD file types as well, as long as those files contain 3D face data, such as from DXF, DWG, and FBX files. These non-IFC file types require some extra steps as outlined below.

To use this action, perform the following steps:

1. Import all CAD files that contribute to the model into the same Pathfinder model.
2. If any of the imported files were not IFC, set the Import Type for the objects imported from those files. These files default all objects to the Import Type, Obstruction, so this only needs to be done for non-Obstruction objects.
   Some fast ways to do this include:
   1. If the imported objects are grouped together in the navigation view by type, select the group containing the objects such as the one containing all the doors, and set the Import Type in the property panel to Door.
   2. If the imported objects contain the object type in their name, such as Door43, use the search tool (Edit→Find) to select all with the text Door in the name. Then set the Import Type to Door on the whole selection.
3. Delete any objects that should not contribute to the Pathfinder model or set their Import Type to <ignored>. This may be necessary, for instance, if the file contained stand-in objects, such as the building envelope.
4. In the Model menu, click Generate Model from BIM. This will show the Generate Settings dialog as explained in Section 4.3.1.2.
5. Set the desired properties for generating the model, and click Generate. This will generate rooms, stairs, and doors for the entire imported model.
6. If any exits still need to be added, do so manually.
7. There may be extra detached rooms that are not needed in the model. An easy way to remove these is to first right-click a room that should be in the result, and click Select Connected Components from the right-click menu. Select the Entire graph option in the dialog, and click OK. Hide the selected objects. Repeat this until all required components have been hidden. The remaining extra rooms can be selected and deleted.

If only a subset of the imported objects needs to be modeled in Pathfinder, either set the Import Type for unnecessary objects to <ignored> before generating the model with the above steps or perform the following instead:

1. Select the imported objects that should be turned into navigation elements. The selection does not have to include objects with Import Type set to Obstruction, as obstructions are automatically subtracted during model generation.
2. Right-click the selected objects, and from the menu, click Generate Model from BIM Selection.
3. In the Generate Settings dialog, enter the desired settings and click Generate.

4.3.1.1. Generate Process

The following table describes how Pathfinder converts imported objects into Pathfinder navigation elements based on their Import Type and any additional properties that may have been imported along with the object:

Import Type	Pathfinder Type	Details
<ignored>	–	These objects are completely ignored when generating the model.
Door	Door	To generate a Pathfinder door, Pathfinder first obtains the geometry of the imported door that will define the shape of the Pathfinder door. If the imported door has an associated wall opening, the wall opening’s geometry is used. If not, the door’s geometry is used. The minimum bounding rectangle of the geometry is then used to define the Pathfinder door shape. If the door’s geometry was used and the door has an associated opening width property, the resulting door will be no wider than this opening width. The minimum bounding rectangle is then extruded into a box such that the bottom of the box is slightly below the bottom of the source geometry and the top is slightly above the top of the source geometry. This box is then subtracted from the generated rooms, and a Pathfinder door is used to fill the gap.
Escalator	Stair and Room	The conversion is performed the same as for Import Type Stair. If the resulting stair must be treated as an actual escalator, its properties must be set after generating the model. See Section 3.7 for more information.
Floor	Room	Pathfinder will identify the potential walking surfaces of the imported objects. It will then identify all potential obstructions and subtract them from the walking surfaces. NOTE: With the exception of objects with Import Type, Door and <ignored>, all imported objects are treated as obstructions to flow, even if they don’t have Import Type, Obstruction.
Moving Walkway	Room	The conversion is performed the same as for Import Type Floor. If an actual moving walkway is needed instead of a room, delete the generated room and create a moving walkway as described in Section 3.8.
Obstruction	–	These objects do not directly become Pathfinder objects. Instead they become either holes in the rooms or thin boundary walls.
Ramp	Room	The conversion is performed the same as for Import Type Floor. If an actual ramp is needed instead of a room, delete the generated room and create a ramp instead as described in Section 3.6.
Stair	Stair and Room	To generate a Pathfinder stair, the imported object’s steps are first generated as if they were rooms. Like with rooms, overhead obstructions, such as railings, are subtracted from them. After this, the steps of the stair are connected together using Pathfinder stairs. If multiple steps can be strung together in a row and have similar rise and run characteristics, they all become one stair. Otherwise, they are separated into multiple stairs so that each stair has similar rise/run to the underlying imported geometry. This process may leave part of the stair geometry, such as the landings, as rooms.

4.3.1.2. Generate Settings

When using the Generate Model from BIM action, various settings can be specified in the Generate Settings dialog as shown in Figure 73.

The following settings are available in the Generate Settings dialog:

Max Slope

Determines the maximum slope of a floor to be considered as a walkable surface. A slope of 0° indicates a flat surface, while a slope of 90° is vertical.

Max head height

The maximum height for objects to be considered overhead obstructions. Overhead obstructions are used to cut out portions of the resulting rooms to prevent occupants from walking in that space. Imported objects higher than this will not be counted as obstructions.

Generate from tops of solids

If checked, walkable surfaces will only be generated from closed, solid objects if the surface is on the top of the solid (i.e. there are no other surfaces in the object above it). This helps reduce the number of surfaces that will be considered for generating rooms, which also reduces the computation time. The result should be the same, however, if this is checked or unchecked. If it seems like any rooms are missing from the result, try unchecking this option.

Exclude rooms in solids

If checked, rooms that were generated inside solid objects such as walls are excluded from the result. This helps reduce the number of resulting rooms. If any rooms appear to be missing from the result, try unchecking this option.

Close gaps smaller than x

If checked, thin boundary edges are inserted into a room anywhere where there are room boundaries close together. This is useful in combination with Exclude rooms with area less than x to reduce the complexity of the model.

Exclude rooms with area less than x

If checked, rooms with small area are excluded from the result. This is useful in combination with Close gaps smaller than x to reduce the complexity of the model and remove portions where an occupant would not walk, such as between a desk and wall.

Use imported names

If checked, the resulting navigation elements (rooms, doors, stairs) will be named after the imported object from which they derived. Otherwise, a generic name will be used.

Generate doors

If checked, adds Pathfinder doors to the navigation mesh from the imported doors.

Generate stairs

If checked, adds Pathfinder stairs to the navigation mesh from the imported stairs.

Max vertical step distance

The maximum allowed distance in the Z direction between steps of a stair. If an imported stair contains any consecutive steps further away than this, they will not be connected.

Max horizontal step distance

The maximum allowed distance in the XY direction between steps of a stair. If an imported stair contains any consecutive steps further away than this, they will not be connected.

Min stair width

The minimum width of resulting stairs. If an area that looks like a stair is narrower than this distance, it will not result in a stair.

4.3.1.3. Limitations

While the Generate Model from BIM action can quickly provide a good starting point for a Pathfinder simulation, it does have some limitations, including:

• Escalators are only supported as Pathfinder stairs. Their speed and direction are not determined during extraction.
• Moving walkways are only supported as Pathfinder rooms. Their speed and direction are not determined during extraction.
• Elevators are not currently supported.
• Generated doors may be slightly wider than the actual door opening. This is because the shape of the door is determined from either the imported door’s associated wall opening or the door geometry. In the former case, the actual door opening may be slightly smaller than the wall opening due to the door jam. In the latter case, the door geometry often includes door trim, which may be several inches wider than the actual door opening. In addition, some CAD packages may export a curtain wall door with windows on the side as one door object. In this case, the resulting door may be quite a bit wider than the actual door opening because the wall opening/door geometry would include the side windows.
• Pocket doors might be twice as wide as they should be since their opening may include the space inside the walls.
• Doors might be thicker/deeper than the surrounding wall if the CAD package that exported the IFC file uses deep wall openings rather than openings that are just deep enough to cut out an opening in the wall. This should not significantly impact the simulation unless the opening is extremely deep.
• The presence of a door threshold may prevent a door from generating correctly.
• Pathfinder stairs are only generated from objects marked with the Import Type, Stair. Some objects, such as steps in a stadium might look like stairs but are actually marked as floors. In this case, stairs will not be automatically generated, and will look like small, disconnected rooms instead.
• Pathfinder may treat some objects as obstructions that should not participate in the extraction process, such as a stand-in object representing the building envelope. This is caused by limitations in the IFC format or the exporting CAD package, where these objects are marked with the entity type, IfcBuildingElementProxy. This type is merely a stand-in data type for objects not inherently supported by the IFC standard. They may or may not be physical objects in the model, and there is currently no way to differentiate, so Pathfinder treats them all as obstructions.

4.3.1.4. Troubleshooting CAD Import

Depending on the imported CAD data, some problems may arise when generating the Pathfinder model. Table 4 below may help determine the source of the problem and resolve it.

Problem	Cause	Solution
There is a wall in the middle of a generated room where there was no obstruction or there is a gap between rooms when they should be connected.	The wall/gap might actually be a very thin gap that exists between adjacent imported slabs. Pathfinder does not currently close these small gaps automatically.	Either draw a door along the edge that bridges the gap or adjust the geometry of the rooms and merge them together.
A generated door should connect two rooms but is an exit instead.	This can happen if the imported door had no associated wall opening, the door’s geometry was thinner than the surrounding wall, and there is no slab or other floor object under the door.	Select the door and use the manipulation tool to connect the door to the other side of the door opening.
A generated door appeared where it wasn’t expected.	This may happen if a single door was broken into several pieces and/or objects were marked as doors that weren’t actually doors. For instance, this might happen if the door trim is modeled as a separate object than the actual door, and the trim is also marked as a door. In this case, the piece of trim is modeled as a separate door.	Delete the door and draw manually instead.
A generated door was too small.	This is usually caused by the same problem as above.	Select the door and change the Width in the property panel to the desired size or delete and redraw the door if this does not work properly.
A generated door was too wide.	This can happen due to limitations in the door extraction algorithm, see Section 4.3.1.3.	Select the door and change the Width in the property panel to the desired size.
A door is missing	The imported object’s Import Type was not set to Door, or the door had no walking surface under it, did not have an associated wall opening, and was thinner than the surrounding wall. This might also happen if there is a door threshold.	Draw the door manually.
A room is missing	This may either be because the imported object defining the floor did not have its Import Type set to Floor or the Exclude rooms in solids option was turned on and there is a solid object in the model marked as an obstruction that should not be in the model, such as one representing the building envelope.	Undo the import, ensure the imported object’s Import Type is set to Floor, and delete any objects that should not be in the model. Then try generating the model again. If this still does not work, draw the room manually.
A stair is missing	The imported stair object was not marked as a Stair or the step distances exceeded the limits set in the generate settings.	Undo the import, set the Import Type to Stair, and then perform the Generate Model from BIM action again, or draw the stair manually.
An imported stair was broken into several Pathfinder stairs.	This can happen if an imported stair does not conform to a Pathfinder stair, such as with spiral stairs. This might also happen if there are multiple directions from which an occupant could step down off a step of the stair. Another cause could be that the step rise/run changed drastically from one step to another, such as if the top or bottom step does not align exactly with the connecting slabs.	If the stair should have been generated as a single Pathfinder stair, delete the generated stairs and draw the stair manually.
The steps of the generated stair do not match the steps of the imported stair exactly.	This can happen if the steps of the imported stair do not have a consistent step height or tread depth or the imported stair did not line up exactly with the slabs it was connecting. In this case, Pathfinder averages the rise/run of the resulting steps over the entire rise/run of the stair, which may cause the steps to be slightly out of alignment with the imported stair.	If desired, select the Pathfinder stair and change its step rise/run in the property panel.
An elevator is missing.	Generating elevators is not currently supported.	Create the elevator manually, see Section 3.9.
An escalator has extra steps off of the side.	Escalators are generated as stairs. Pathfinder generates stairs using a generic algorithm where any flat surface can be treated as a step. If some of the geometry looks like it might be a step, Pathfinder will create a stair going to it.	Delete the extra stairs.

4.3.2. Extract Rooms Individually

While automatic model generation should work for most 3D CAD files, it may not always produce the desired result, the user might want more control over the rooms that are generated, or it might just be too prohibitive to set the Import Type for some non-IFC CAD files.

Pathfinder provides an Extract Room tool that can address these issues. This tool allows rooms to be extracted individually using a flood-fill algorithm. While it may take more effort to extract all the necessary rooms, it does not require objects to have an Import Type specified unless an object is to be ignored.

To use the Extract Room tool:

1. Select the tool from the drawing tool panel on the left of the 3D or 2D view. The tool properties are shown in Figure 74.

   Max Slope

   Refers to the maximum grade that a person can walk on. Only imported polygons that have a slope less than this will be included in the result.

   Max Head Height

   Refers to the maximum height of all the agents that will be included in the simulation. This parameter is used to subtract overhead obstructions from the resulting room.

   Gap Tolerance

   Provides some control in dealing with imperfections in the imported data. If walls are closer than the gap tolerance, Pathfinder will add an extra thin wall in that area, helping to split of rooms so the result does not bleed into undesired areas.

2. Once the appropriate parameters have been chosen, either enter a location on the floor of the desired room into the property panel or click this point in the 3D or 2D view.
3. If this point does not have any overhead obstructions within Max Head Height and the point is on a polygon with a slope less than Max Slope, Pathfinder will march out from this point on the imported geometry’s polygons until it finds the boundaries of the room. It will also subtract overhead obstructions within Max Head Height from the resulting room.

Below is an example of a 3D CAD model Figure 75 and a room extracted from it Figure 76.

When using the extract room tool, Pathfinder will include all imported geometry with faces, even if hidden. If an object must be excluded from room extraction, the object’s Import Type must be set to <ignored> before performing extraction. Otherwise, this tool completely ignores the Import Type of the objects.

4.3.3. Working with 2D CAD

2D CAD data can be worked with in two ways:

• It can be used as a guide for drawing rooms similarly to background images with the added benefit of being snapped to
• It can have rooms extracted from it similarly to 3D imported geometry as described above.

To sketch the rooms using the built in drawing tools, refer to Section 3.2.

Extracting rooms from 2D CAD data works similarly to extracting rooms from 3D CAD data. As in 3D extraction, the Extract Room tool is used. In addition, the user must click a point in the model with the tool, and one room will be extracted.

The main difference from 3D extraction is that the clicked point must not lie on any 3D imported faces marked for room extraction; instead it must be in empty space (or on the background rectangle imported with a 2D floorplan). The clicked point should also be surrounded by imported 2D lines. These lines will form the boundary of the resulting room. For this reason, any lines that do not contribute to the room’s boundary, such as notations, symbols, etc. should be deleted, hidden, or excluded from room extraction prior to clicking the extraction point.

To manually exclude imported geometry from floor extraction, select the geometry and from the property panel, set the Import Type to <ignored>. When determining which imported geometry to extract rooms from, the 2D room extraction tool will automatically exclude hidden objects and those manually ignored.

Once the desired point is clicked, the surrounding 2D lines looking at the model from the Top View will be projected along the Z axis onto the active floor’s working Z plane. These projected lines will then be used to define the room around the clicked point. If the surrounding lines do not form a closed boundary as shown in Figure 77, the resulting room will spill outside of the lines and form a room around the bounding box of all the lines as shown in Figure 78. In this case, this outer portion of the room can be separated from the inner portion using the Thin Wall tool as discussed in Section 3.3.2. Once separated, the outer portion can be deleted.

When the extraction tool is finished finding a room, the room will lie in the working Z plane of the active floor.

4.3.4. Working with Images

Working with background images requires the user to draw all rooms, doors, and stairs over the background image (Figure 79). Because the drawn navigation geometry will cover the background image, it may be preferable to make the navigation geometry transparent. This can be accomplished by selecting the drawn navigation components and lowering the opacity in the property panel. Figure 80 shows a background image with rooms and doors drawn on top, with a lowered opacity for the drawn rooms.

To draw rooms on top of a background image, refer to Section 3.2.

4.3.5. Filling in Missing Pieces

Once rooms have been extracted using the Extract Room tool, the model will still be missing doors and stairs (Figure 81). Doors and stairs must be added manually as discussed in Section 3.4 and Section 3.5 of this guide.

One feature that may be of particular interest to help this process, however, is the internal door feature of the door tool. This feature automatically finds areas within a room that look like potential doorways and can be used to create a thick door in this area.

To use this feature:

1. Select the door tool.
2. In the property panel for the tool as shown in Figure 44.

   Max Width

   Refers to the maximum width of the doorway to search for.

   Max Depth

   Refers to the maximum thickness of the doorway. These numbers may need to be larger than for the normal creation of a door to find potential doorways.

3. Once the appropriate parameters have been entered, move the cursor over the desired doorway (Figure 82). A door preview will be displayed. If it doesn’t, adjust the search parameters in the property panel and try again.
4. If the door appears correctly, left click the mouse button. The doorway area of the room will be subtracted from the room, and the thick door will be created in its place (Figure 83).

4.3.6. Flattening and Z Location

Sometimes when importing from 3D CAD models, extracted rooms may not be at the proper height or may have some undesired slope. These issues can be corrected either before or after extracting rooms by using the Set Z dialog (Figure 84).

To do so, follow these steps:

1. Select the objects that need to be corrected.
2. Right-click the selection and select Set Z.
3. This will open the Set Z dialog as shown in Figure 84.
4. Set the desired options, and select OK to modify the geometry in the selection.

The dialog shows the following properties and options:

Selection Bounds

Shows the minimum and maximum Z locations of the selected objects.

Flatten Objects

If selected, each object in the selection will be flattened so that all of its geometry lies in the same plane. The location of the plane is determined by the Move to option.

Move to

This specifies how the geometry should be moved in the Z direction. This can be one of the following values:

Absolute Z

All the selected objects will be moved to the same Z plane. If Flatten Objects is not selected, each object is moved such that its minimum Z touches the specified plane.

Z Offset

Each object in the selection is moved by the specified Z Distance. If Flatten Objects is selected, the object is first flattened to the plane that touches the minimum Z of the object’s original geometry, and then moved by the Z Distance. \(z=z_{\text{offset}}+z_{\text{multiplier}}*n\)

4.3.7. Materials

Materials define advanced display properties that can be applied to faces contained in the imported geometry. They are only shown when the Show Materials option is selected in the 2D View or the 3D View, see Section 2.3. Materials can be shared among faces; when a material is edited, all faces referencing that material are updated.

Materials are extracted from import files in different ways, depending on the file type:

DWG, FBX, DAE, OBJ

These files have a concept of materials. Each material that is referenced by an object in the file will be imported into Pathfinder. Currently, Pathfinder supports the diffuse color, diffuse texture, opacity color, ambient color, specular color, and emissive color settings of the material. Only the diffuse color and texture can be changed in the material dialog, however.

FDS and PSM

Pathfinder materials are constructed from the color and texture settings of the surfaces in these file types.

To see the materials that have been imported from the DWG or PSM file, on the Model menu, select Manage Material Database. The Material Dialog will appear as shown in Figure 85.

Pathfinder provides some default database materials. Most of these materials start with the prefix, psm_ as in PyroSim. Other materials were either created manually by the user or were imported with the CAD or PyroSim file.

Materials can be added manually by clicking New under the material list. Materials can also be created from an initial texture image on disk by clicking Import. The image is copied into the database directory. Newly created materials are added to the database, and can be used across instances of Pathfinder.

Materials can be deleted by clicking Remove under the material list. If the material exists in the database, all its associated files in the database directory will also be permanently removed.

The following material properties can be edited from this dialog:

Texture Width and Height

Define the dimensions of the texture image in the model. For instance, if the image depicts a 4x4 array of bricks with no mortar, and each brick is 8"x3", the Width would be 32" and the height would be 12".

Diffuse Color

Selecting this option makes the material display with a solid color.

Diffuse Texture Image

Selecting this option makes the material show a texture image.

Opacity Value

Defines the opacity of the material.

Opacity Texture Image

Defines a texture which controls the opacity of the material.

4.3.8. Advanced Material Properties

Additional material properties can be edited by pressing the Advanced Materials button. This will show the Advanced Materials Dialog for the currently selected material.

Most properties in this dialog can be specified as either a constant color/value or as a texture image. The following material properties can be edited from this dialog:

Ambient

Defines the color used to modulate ambient lighting applied to the material. This will only be applied when Image Based Lighting is disabled. Selecting the From Diffuse/Albedo option for this channel causes the Diffuse channel value to modulate ambient lighting instead.

Emissive

Defines the amount and color of light emitted by the material.

Normal/Bump

Whether to use normal mapping or bump mapping for the material.

Normal

The normal map used for the material.

Y-Down Normals

Whether or not to invert the y-component of the provided normals. This should be enabled for normal maps designed for DirectX. Check any documentation that comes with the material to determine if this applies.

Bump

The bump map used for the material.

Bump Scale

The strength of the bump map effect.

Displacement/Height

The parallax displacement or height map to use.

Parallax Scale

The strength of the parallax mapping effect. This unit of this scale is purely visual, but it should be kept low to prevent rendering artifacts.

Invert Parallax

Whether or not to invert the displacement/height map. This should be enabled for height maps.

Workflow

The material workflow to use. Provided options are Specular (Basic), Metallic (PBR), and Specular (PBR). Materials with a Specular map are designed for either the Specular (Basic) or Specular (PBR) workflow. Specular materials with a Roughness, Glossiness, or Ambient Occlusion map are meant for the Specular (PBR) workflow. Materials with a Metallic map are designed for the Metallic (PBR) workflow.

Depending on which workflow is selected, the following additional properties are provided:

Specular

Defines the specular reflectance of the material. This property is only available in the Specular (Basic) and Specular (PBR) workflows.

Metallic

Defines whether or not the material is metallic. This property is only available in the Metallic (PBR) workflow.

Shininess

Defines how shiny the material’s surface is. This property is only available in the Specular (Basic) workflow.

Roughness/Glossiness

Determines whether to use roughness or glossiness to define the material’s microsurface. This option is only available in the Metallic (PBR) and Specular (PBR) workflows.

Roughness

Defines how rough a material’s microsurface is. This is the exact inverse of Glossiness. This option is only available in the Metallic (PBR) and Specular (PBR) workflows.

Glossiness

Defines how glossy a material’s microsurface is. This is the exact inverse of Roughness. This option is only available in the Metallic (PBR) and Specular (PBR) workflows.

Ambient Occlusion

Provides additional shading information for the material. Note that this property is not related the scene-wide Ambient Occlusion in Results. This property is only available in the Metallic (PBR) and Specular (PBR) workflows.

4.4. Importing FDS Output Data

Pathfinder can use the PLOT3D data output from FDS to create time history data for each occupant as they move throughout the simulation. In cases where FDS PLOT3D output data is available for \(CO\) Volume Fraction, \(CO_{2}\) Volume Fraction, and \(O_{2}\) Volume Fraction; Pathfinder will also output Fractional Effective Dose (FED) for each occupant specified.

FDS data integration is a measurement only and does not alter the movements or decision making within the Pathfinder simulation. However, enabling this feature causes simulations to require additional runtime because of the additional processing load relating to reading the FDS output files and mapping PLOT3D data to occupants.

To enable FDS Integration:

The dialog (Figure 87) will display information about the attached SMV file and indicate which quantities were found.

For more information about how Pathfinder computes the maximum walking speed of occupants in smoke, see (Pathfinder Technical Reference, n.d.).

To enable FED and PLOT3D quantity output for one or more occupants:

Once the simulation has completed, CSV data is available for each specified occupant in the output folder. See Section 14.8 for more information on the CSV data.

For information on how FED is calculated or how its use was verified in Pathfinder, see (Pathfinder Technical Reference, n.d.) and (Pathfinder Verification and Validation, n.d.) documents respectively.

4.5. Importing Custom Avatars

When viewing occupants as people in either Pathfinder or Pathfinder Results, occupants and vehicles are represented by a 3D avatar. Avatars are chosen in either the Edit Profiles dialog (see Section 5.1) or the Edit Vehicle Shapes dialog (see Section 5.2). While Pathfinder ships with many avatars, they might not cover all modeling scenarios. Custom avatars can be imported into Pathfinder to meet additional requirements.

4.5.1. Custom Avatar Requirements

The following file formats are supported for importing custom avatars:

Occupant Avatars

FBX, DAE

Vehicle Avatars

FBX, OBJ, DAE

Avatar files should follow these rules:

• There should be one avatar per file.
• When using an FBX file, if possible, the textures should be embedded in the file; otherwise, the textures will have to be manually copied to the avatar directory (see Section 4.5.5 below). Other file formats require copying textures.

Occupant avatars have the following additional constraints:

• There should be at least one "animation" where the avatar is in a T-pose or an A-pose or some variation. There can be other animations in the file, but this will adversely affect loading performance.
• Occupant avatars must be "rigged", meaning there is a joint hierarchy specified in the FBX or DAE file. The rig must be human-like.
• Joint names in the FBX or DAE file must follow standard conventions used by industry-wide software.

5.1. Profiles

Pathfinder uses an occupant profile system to manage distributions of parameters across groups of occupants. This system helps you control the occupant speed, size, and visual distributions. To edit occupant profiles, you can use the Edit Profiles dialog (Figure 89).

To open the Edit Profiles dialog: on the Model menu, click Edit Profiles, or double-click the word Profiles in the Navigation View.

To select 3D models:

By clicking the Import button in the 3D Models dialog, custom avatars can be imported into Pathfinder. See Section 4.5 for more information.

5.1.6. Advanced Tab

The Advanced tab provides the following parameters:

Acceleration Time

Is a Steering Mode parameter that specifies the amount of time it takes for the occupant to reach maximum speed from rest or to reach rest from maximum speed. The resulting forward acceleration of each occupant is \(\text{forward_acceleration}=\text{max_speed}/\text{accel_time}\). The occupant uses a separate reverse acceleration of \(2*\text{forward_acceleration}\) and a separate lateral acceleration of \(1.5*\text{forward_acceleration}\).

Persist Time

The amount of time an occupant will maintain an elevated priority when trying to resolve movement conflicts. See the (Pathfinder Technical Reference, n.d.) for more details.

Collision Response Time

The distance ahead at which an occupant will start recording a cost for colliding with other occupants when steering. It is multiplied by an occupant’s current speed to calculate the recording threshold. As an example, with the default value of 1.5 s and the default maximum speed of 1.19 m/s, the occupant will look ahead 1.785 m from their current position to detect potential collisions and calculate costs.

Slow Factor

Specifies a fraction of the occupant’s speed at which they are considered to be slow. A slow occupant will consider backward directions to separate with others, while a fast moving occupant has a tighter, more focused direction.

Wall Boundary Layer

Specifies the distance that occupants try to maintain with walls and other static obstructions.

Personal Distance

The desired distance one occupant will try to maintain with others in a queue. This may be entered explicitly as a distance, from queue area, or from queue density. When entered as a distance, it is defined as the gap distance between the occupants' shapes rather than their center-to-center distance. If entered as an occupant area, the personal distance is calculated based on sphere packing: \(c = \frac{2}{\sqrt[4]{12}}\sqrt{a}-d\) Where \(c\) is personal distance, \(a\) is the occupant area, and \(d\) is the occupant’s shoulder width. Personal distance is calculated similarly when entered as occupant density, except that \(a=\frac{1}{\rho}\) where \(\rho\) is occupant density.

Social Distancing

Enables or disables Pathfinder’s social distancing model for the occupant profile. When enabled, the desired social distance can be set as a constant value or a distribution of values, enabling occupants to have different desired social distances. Social distance is defined differently than Personal Distance in that it is the center-to-center distance between occupants, whereas the personal distance is the gap distance between their shapes. In addition, social distance is enforced more strictly than personal distance and is more useful for maintaining larger distances between occupants (> 1 m).

Each of these parameters (except on/off parameters) can be set using a constant value, a uniform distribution between two values, or either a normal (Gaussian) or log-normal distribution (see Section 5.1.7).

Each occupant in the Pathfinder model is linked to one profile. Profile parameters can be edited in the profiles dialog at any time and the occupants using that profile will be automatically updated. Occupants' profiles can be set when adding the occupants or by selecting the occupants after being created and editing the Profile box in the property panel.

5.1.6.1. Advanced Speed Properties

In most cases, users only need to enter the maximum speed of an occupant in the Characteristics tab of the Edit Profiles dialog. The actual speed of the occupant throughout a simulation will vary according to this speed and a set of assumptions from the Engineering Guide to Human Behavior in Fire (SFPE 2019), which takes into account the type of terrain being traversed (stairs, ramps, etc.) and the density of surrounding occupants. See the (Pathfinder Technical Reference, n.d.) for more information.

Pathfinder allows for fine-grained control over the speed of the occupant, however, and the SFPE assumptions can be customized or replaced with other assumptions.

To do so, follow these steps:

1. In the Model menu, click Edit Profiles to open the Edit Profiles dialog.
2. Click the Characteristics tab.
3. Next to Speed, click the drop-down box and select Advanced as shown in Figure 91.

This will open the Advanced Speed Properties dialog as shown in Figure 92.

As noted in the Advanced Speed Properties dialog, when simulating in SFPE mode, only the maximum speed property is used. All others in the Advanced Speed Properties dialog are ignored.

Clicking Reset to Defaults in the Advanced Speed Properties dialog will reset all advanced speed properties to their default values in Pathfinder.

Each tab in the dialog allows the customization of occupant speed on each terrain type in Pathfinder, including Level Terrain, Stairs, and Ramps.

5.1.6.1.1. Level Terrain Tab

The Speed Density Profile can be used to set the occupant’s speed as a function of the surrounding occupant density, also known as the fundamental diagram. One of three options may be chosen for the profile:

SFPE

The fundamental diagram as specified in the Engineering Guide to Human Behavior in Fire (SFPE, 2003) is used to adjust occupant speed.

Constant

The maximum speed is multiplied by a constant factor to determine the occupant’s speed. In most cases, the occupant will either try to move this speed or stop.

From Table

The speed is entered as a fraction of the occupant’s maximum speed as a function of surrounding occupant density. The values are entered in the Speed-Density Profile dialog as shown in Figure 93. The profile is defined as a piece-wise linear function, where sample points are entered into a table. For densities within the entered range, the speed fraction is interpolated. For densities outside the range, the speed fraction is equal to that entered for the nearest specified density. A preview of the fundamental diagram is shown to the right of the table. The SFPE profile, which is the default profile, may be loaded by clicking Load SFPE profile below the table.

5.1.6.1.2. Stairs Tab

The following properties may be entered in the Stairs tab:

Speed Fraction Up

Defines a speed factor when the occupant travels up stairs.

Speed-Density Up

Defines the speed-density profile to use when the occupant travels up stairs.

Speed Fraction Down

This specifies the speed fraction when the occupant travels down stairs.

Speed-Density Down

This specifies the speed-density profile to use when the occupant travels down stairs.

The above parameters define a factor that is multiplied by occupant’s maximum speed to determine their speed up or down stairs.

The factor may be specified in one of three ways:

SFPE

The assumptions from the SFPE Engineering Guide to Human Behavior in Fire are used to determine the speed fraction up stairs. This option uses the rise and run of the stair to determine the speed.

Constant

A constant factor is applied to the maximum speed.

From Table

The speed factor can be entered as a function of stair slope. Stair slope is defined as step rise/step run. The function is entered as a piece-wise linear function.

Additionally, the Speed-Density Up and Speed-Density Down parameters have the From Level Terrain option. This option forces the occupant to use the same speed-density profile as specified on the Level Terrain tab when the occupant travels up or down stairs.

5.1.6.1.3. Ramps Tab

The Ramps tab has nearly identical properties available as on the Stairs tab. The only difference is that Speed Fraction Up and Speed Fraction Down are entered in terms of the ramp’s geometric slope rather than step slope. The geometric slope is determined per triangle in the resulting navigation mesh and depends on the triangle’s normal direction.

5.1.9. Customizing Occupants

When occupants are selected, their property panel appears as shown in Figure 94. Occupants can be given custom profile data once they are added to the model. This can be done by selecting a set of occupants and checking the box next to the parameter to be customized.

Percentage-based distributions can also be used to assign occupant profiles and behaviors to a group of occupants, see Section 5.5.

Customized properties will be overwritten if an occupant switches their profile during simulation, see Section 5.3.3.8.

When using custom profile data, only constant values can be used for occupant parameters. In addition, once a parameter is customized, any changes to that parameter in the profile will not affect the customized value.

Occupants with individually customized parameters can easily be found by right-clicking all or a sub-set of occupants and selecting Select Customized Occupants from the right-click menu if any exist in the selection.

5.1.10. Profile Libraries

Profiles can be saved and reused using profile libraries (Figure 95). Profile libraries are managed in the Profile Libraries dialog. To open the Profile Libraries dialog, on the Edit Profiles dialog, click Add From Library Alternatively, the Profile Libraries dialog can also be opened by clicking Edit Profile Libraries on the Model menu.

The list on the left side of the dialog shows all profiles contained in the current Pathfinder model. The list on the right side of the dialog shows all profiles stored in the profile library. Profiles can be moved between the lists using the buttons in the middle of the dialog. Create New Library clears the list of library profiles so that a new library can be created. Load Library opens a profile library from file. Pathfinder supports loading profiles from profile library files (PLIB) and from standard Pathfinder model files (PTH).

To create a Pathfinder library file (PLIB) based on profiles in the current model:

1. Click Create New Library to create a new empty library.
2. Use the arrow buttons to copy profiles from the current model to the library.
3. Click Save Current Library

The dropdown menu on the right side of the dialog can be used to load predefined libraries. To fill the predefined libraries box, Pathfinder scans two locations: a folder in the Pathfinder installation shared by all users and a folder in the current user’s APPDATA path, see Table 7.

PLIB File Location	Suggested Use
C:\Program Files\PyroSim 20XX\lib\profiles (or alternate install folder)	Built-in libraries included with Pathfinder. Administrator access is required to modify this location. Changes to PLIB files from this location will affect all users sharing the computer.
%APPDATA%\Pathfinder\profiles	Recommended location for storing PLIB files. Non-admin users have write access to this folder. Changes to PLIB files in this location will affect only the current user.

All predefined profile libraries are opened as read-only to prevent accidental modification. To modify a library, you will need to resave to overwrite the existing PLIB file. See Appendix A, for more information on the occupant profiles provided with Pathfinder.

5.2. Vehicle Shapes

An occupant can be assigned a vehicle to use throughout the simulation. When using a vehicle, an occupant uses the shape of the vehicle rather than the default cylinder shape when performing collision detection. Any convex polygon can be used as the vehicle shape.

Vehicle shapes are not intended to be used as shapes of regular occupants. A vehicle movement is fundamentally different from an occupant movement. Unlike regular occupants, vehicles are not allowed to move sideways. Consequently, the vehicles follow a different path, which accounts for this movement restriction. Vehicles also avoid collisions with other occupants and walls differently from regular occupants. Finally, vehicle movement uses more complex calculation, which can increase the run time of the simulation.

The vehicles can be created and customized in the Edit Vehicle Shapes dialog (Figure 96). To open the Edit Vehicle Shapes dialog: on the Model menu, click Edit Vehicle Shapes.

The Description box provides a place to enter descriptive text. This value is not used outside the Edit Vehicle Shapes dialog.

The Vehicle Preview shows a graphical preview of the projected shape of the vehicle and provides additional capability to add, remove, and change points of the vehicle shape, the pivot location, and the positions of attached agents.

The dashed lines depict the horizontal and vertical axes. Their intersection (by default point x=0, y=0) is the pivot of the vehicle, around which the vehicle body rotates. The red arrow points in the direction of the movement of the vehicle. The pivot can be moved both inside and outside of the vehicle shape.

A point can be added to the vehicle shape or positions of attached occupants by right clicking inside the graphical editor. When moving the cursor close to a point, the point changes its color to orange indicating that it can be selected. A selected point changes its color to yellow. This selection is also displayed in the point editors on the left side of the dialog.

Any point can be moved by selecting and dragging, and it can be deleted by right clicking and selecting the Delete Point option. Mouse wheel can be used to zoom in and out, and mouse dragging can be used to move around. Reset View button resets the view so that all points are visible. The Undo/Redo buttons can be used to undo/redo any action within the 2D Graphical Editor.

A warning will appear at the bottom of the dialog in case constraints like minimum number of points in the vehicle shape, convexity, distance of assisting occupants from the vehicle shape etc. are violated.

For more information about the navigation of polygonal shapes in Pathfinder see the Pathfinder Technical Reference (Pathfinder Technical Reference, n.d.).

5.3. Behaviors

Behaviors in Pathfinder represent a sequence of actions the occupant will take throughout the simulation. Once they occupant has completed all actions, they are removed from the simulation. Actions may be added that can make the occupant wait or travel to a destination, such as a room, point, or exit.

The last destination for the occupant can be thought of as the occupant’s sink. By default, there is one behavior in the model called "Goto Any Exit". This behavior simply makes the occupant move from their starting position to any exit present in the model by the fastest route.

As with profiles, any number of occupants can refer to a single behavior. Any changes to the behavior will be reflected in referring occupants.

5.3.1. Creating a New Behavior

To create a new behavior:

1. Right click the Behaviors node from the Navigation View, and from the right-click menu, click Add a Behavior, which will open the New Behavior dialog shown in Figure 97.
2. In the New Behavior dialog, enter a behavior name, and optionally specify an existing behavior to base the new behavior on. Using this option will copy all the actions from the existing behavior.

With the new behavior selected, the behavior property panel will appear as shown in Figure 98.

Initial Delay

Specifies an initial delay that makes the occupant wait at their starting position before moving to the next action. If this link is clicked, it will show a dialog where different distribution curves can be entered for the delay, similar to those discussed in Profiles.

5.3.2. Adding Actions

Additional actions can be added to any behavior, such as going to a room, a waypoint, an elevator, or simply waiting in place. To add an action, select a behavior or existing behavior action. The property panel (Figure 99) will show a drop-down button with the description of an action that can be added. To add the currently shown action, simply click the button. To add a different action, click the down-arrow shown to the right of the button and select the desired action from the behavior actions list.

Once the desired action is clicked, a creation panel will be shown above the 3D/2D View depending on the action. Enter the desired parameters in the creation panel as discussed in the following sections, and then click Create to create the action and append it to the behavior. If the behavior itself was selected when adding the action, then the new action will be appended to the end of the list. If, instead, an action was selected when the new action was created, then the new action is inserted directly after that selected action. If the action is an ending action (includes all actions below the separator in the behavior actions list), the action will always be added at the end. If the behavior already has an ending action, it will replace the existing ending action.

Actions always occur in the order shown in the Navigation View. For instance, as shown in Figure 100, an occupant using "Behavior1" would first go to any elevator, then go to "Room00", then wait for 20 seconds, then go to "Room09". After reaching "Room09", the occupant will be removed from the simulation. The actions can be reordered at any time by dragging and dropping an action in the list in the Navigation View.

5.3.3. Behavior Action Types

Action	Ending Action?	Description
Goto Waypoint	No	Specifies that an occupant should go toward a specific point on the navigation mesh.
Goto Rooms	No	Specifies that an occupant must select a room out of a set, and go to it.
Goto Elevators	No	Tells an occupant to use evacuation elevators.
Goto Queue	No	Specifies that an occupant should join a designated Queue.
Wait	No	Tells an occupant to wait in their current location for a specified amount of time.
Wait Until	No	Instructs an occupant to delay their movement until a specified simulation time passes.
Change Behavior	No	Instructs an occupant to change a behavior to a new behavior picked randomly from a behavior distribution.
Change Profile	No	Instructs an occupant to change to a different profile picked randomly from a profile distribution.
Assist Occupants	No	Instructs the occupant to join an assisted evacuation team and begin assisting occupants who request assistance from that team.
Wait For Assistance	No	Indicates that the occupant should wait for assistance from other occupants.
Detach from Assistants	No	Detaches a client from their assistants, allowing the assistants to continue helping other clients.
Resume Prior Behavior	Yes	Instructs the occupant to continue using the behavior prior to the current behavior.
Remove Occupant	Yes	The occupant will be removed from the simulation.
Wait Until Simulation End	Yes	The occupant will wait in their current location until the end of the simulation.
Goto Refuge Rooms	Yes	Instructs the occupant to go to one of a set of rooms marked as refuge areas.
Goto Exits	Yes	Instructs an occupant to take the fastest route to a set of exits.

5.3.3.1. The Goto Waypoint Action

A Goto Waypoint action specifies that an occupant should go toward a specific point on the navigation mesh. Once they arrive within a certain radius of the point, they will move on to the next action in their behavior.

To add one of these actions:

1. Click the Goto Waypoint button from the behavior actions list
2. Enter the Location or click a point on the model
3. Enter the Arrival Radius or drag the mouse after you click the location to specify the radius

These parameters can be entered manually in the creation panel or be filled in by clicking a point on the navigation mesh in the 3D or 2D View or click-dragging to specify the location+arrival radius. When clicking or click-dragging, the action is created when the mouse button is released.

5.3.3.2. The Goto Rooms Action

A Goto Rooms action specifies that an occupant must select a room out of a set, and go to it. Once they cross a door into the room, they are considered to be in the room and can move on to the next action in their behavior. If multiple rooms are specified for the action, the occupant will go to the one that is fastest to reach.

To add a Goto Rooms action:

1. Click the Goto Rooms button from the behavior actions list.
2. Click the Rooms link to specify the rooms with a dialog (see Section 2.6.1 for help using the Object Sets dialog), or left-click the desired rooms in the 3D or 2D View.
3. Right-click in the 3D/2D View to finish selecting the rooms and create the action, or click Create.

5.3.3.3. The Goto Elevators Action

A Goto Elevators action tells an occupant to use evacuation elevators. When using this action, an occupant will go to a specified elevator, call it, wait for it to arrive, enter it, and then wait for it to reach the discharge floor. Once they reach the discharge floor, they can begin their next action. The Goto Elevators action can only be used for occupants who are not on the discharge floor of the desired elevator. If multiple elevators are specified for the action, the occupant will use the one that allows them to reach the discharge floor fastest.

To add a Goto Elevators action:

1. Click the Goto Elevators button from the behavior actions list.
2. Either click the Elevators link to specify the desired elevators with a dialog (see Section 2.6.1 for help using the Object Sets dialog), or left-click the desired elevators in the 3D or 2D View.
3. Right-click in the 3D/2D View to finish selecting the elevators and create the action, or click Create.

5.3.3.4. The Goto Queue Action

A Goto Queue action specifies that an occupant must select a Queue out of a set, and go to it. When using this action, the selected Queue will direct the occupant’s movement through available queue paths and service points and then releasing the occupant to the next behavior action once it is complete.

To add a Goto Queue action:

1. Click the Goto Queues item from the Add Action dropdown list.
2. Click the Queue link to select the queues with a dialog (see Section 2.6.1 for help using the Object Sets dialog). Both queues and queue groups can be selected. If a queue group is selected, the queues in that group do not need to be selected. Alternatively, left-click the desired target queues in the 3D or 2D View.
3. Click the Create button

5.3.3.5. The Wait Action

A Wait action tells an occupant to wait in their current location for a certain amount of time. Once that time has elapsed they will begin their next action.

The manner in which they wait will vary depending on their most recent destination. For instance, if their previous destination was a waypoint, they will try to stay close to the center of the waypoint. If the previous destination was a room, they will try to move toward the furthest point in the room away from all active doors. This allows other occupants to enter the room.

If their previous destination is an elevator, they will first move toward the walls as in waiting in a room, and then stand still when the elevator travels. In all cases, a waiting occupant will move out of the way of occupants headed toward a destination unless the destination overlaps with the waiting occupant’s most recent destination.

To add a Wait action:

1. Click Wait from the behavior actions list
2. Specify the Wait Time

5.3.3.6. The Wait Until Action

A Wait Until action instructs an occupant to delay their movement until a specified simulation time passes. This action is useful for synchronizing movement of many occupants at a time. Occupants fill space during a Wait Until action per the same rules described for the Wait action. Wait Until actions can be specified using three different approaches: occupants can wait until a specific time, the next in a list of times, or the next time in a periodic function.

To add a Wait Until action:

1. Click Wait Until from the behavior actions list.
2. Click the time to edit the value, which will show the Wait Until Time dialog as shown in Figure 101.
3. Choose a sub-action from the drop-down.
4. Specify the required parameters.
5. Click OK on the Wait Until Time dialog.
6. Click Create.

Within the Wait Until Time dialog, there are three sub-actions available:

Wait until a specific time

This action tells occupants to wait in their current location until the simulation time passes the specified time. If the time has already passed when the occupant begins this action, they will immediately proceed to their next action.

Wait until next scheduled time

This action allows the user to specify a list of wait times. When an occupant begins the wait action, they compare the simulation time to the list of specified times, and wait until the first time greater than the simulation time. If the simulation time is greater than any specified time, the occupant immediately proceeds to the next action.

Wait until next periodic time

This action sets up a periodic list of times.

Time offset

Specifies the first entry in the time list.

Time interval

Specifies the delay between times in the list.

The list of times is then generated from these parameters. For example, if Time offset is set to 60 s, and the Time interval is set to 10 s, the list of times will be [60, 70, 80, 90, 100, …​]. Similarly to the Wait until next scheduled time action, when the occupant begins this action, they will pick the next time in the list and wait until that time passes.

Both the Time offset and Time interval may be specified as distributions. In this case, each occupant will be given a unique list of times to choose from. For instance, if the Time offset is set to a uniform distribution of [50,60] and the Time interval is set to be constant at 10 s, one occupant may get the list, [52.3, 62.3, 72.3, 82.3, …​], and another occupant may get the list [59.2, 69.2, 79.2, 89.2, …​].

5.3.3.7. The Change Behavior Action

This action causes an occupant to switch its behavior. After this action, the occupant will start performing actions from a different behavior. This new behavior is randomly selected from a given behavior distribution. Besides other behaviors, the same behavior and No Change can also be selected. If the occupant changes behavior to its current behavior, the behavior will be restarted. If the occupant selects to make No Change, the Change Behavior action will have no effect. It is possible to create loops in the behavior references. That way the occupant might keep performing the actions forever (until the end of the simulation). Note that depending on the specific setup, it is possible that actions that come after a Change Behavior action will not be performed by the occupant.

See Section 2.6.2 for help specifying behavior distributions.

5.3.3.8. The Change Profile Action

This action causes an occupant to change their profile, which will override all parameters settable in an occupant profile (Section 5.1). This can be used to change an occupant’s speed, shape, avatar, etc., throughout a simulation. The chosen profile is selected from a list of possible profiles, including a No Change item that will prevent the occupant’s profile from changing.

For profile parameters that are specified as distributions (e.g. max speed), a given occupant will always select a value from the same part of the distribution for that parameter. For instance, if a given occupant starts with a profile whose max speed is a normal distribution, and the occupant’s speed is chosen from the 25^th percentile, any subsequent profile changes will also lead to the occupant’s speed being chosen from the 25^th percentile of the new speed distribution. This ensures that if an occupant’s profile is changed, that parameter will remain consistent for the occupant. In addition, if the parameter does not change with a profile change, the occupant will maintain the previous value. For value sets, such as occupant avatars, it is guaranteed that the occupant will maintain the same value only if the new profile uses the exact same set of values as the previous.

Profile changes can also be used to change an occupant’s shape. It can change from a normal cylinder shape to a vehicle shape. It can also change from one vehicle shape, such as a bed, to another shape, such as a wheelchair. Because vehicles can be used with assisted evacuation (see Chapter 7), take care when switching between shapes during assistance. If an occupant is to change vehicles during assistance, for correct functionality it is best to detach from assistants before changing shapes using a Detach from Assistants action and then re-attach after changing shapes using a Wait for Assistance action.

See Section 2.6.2 for help specifying profile distributions.

5.3.3.9. The Assist Occupants Action

This action is used in assisted evacuation models as discussed in Chapter 7. This action instructs the occupant to join an assisted evacuation team and begin assisting occupants who request assistance from that team. When an occupant joins a team, they become an assistant. Once all occupants requesting assistance have completed their actions for which they wanted assistance, the assistant will begin their next action.

To add an Assist Occupants action:

1. Click Assist Occupants from the behavior actions list.
2. Specify the assisted evacuation Team that the occupant will join.
3. Click Create.

5.3.3.10. The Wait For Assistance Action

This action indicates that the occupant should wait for assistance from other occupants as discussed in Chapter 7. This action requires that the occupants using it have a vehicle shape with at least one attached occupant location as discussed in Section 5.2. When an occupant begins this action, they are considered to be a client, and assistants will approach the client. The client cannot move once they begin waiting for assistants until enough assistants attach to the client to fill all the attached occupant positions. Once all positions are filled, the client begins their next action. The assistant will stay attached to the client until either the client has completed all subsequent actions or the client begins a Detach from Assistants action as described below.

To add a Wait for Assistance action:

1. Click Wait for Assistance from the behavior actions list.
2. Specify the Assisting Teams that will assist the client (see Section 2.6.1 for more information)
3. Click Create.

5.3.3.11. The Detach From Assistants Action

This action indicates that the occupant should detach from their assistant as discussed in Chapter 7. When an occupant begins this action, they are considered to be a client, and currently being assisted in their movement. Once detached, the occupant can proceed to their next behavior without assistance, only if they do not require assistance to move. This action also allows the assistant to move on to the next occupant requiring assistance.

To add a Detach From Assistance action:

1. Click Detach from Assistant from the behavior actions list.
2. Click Create.

5.3.3.12. The Resume Prior Behavior Action

This action resumes the Behavior prior to the current behavior. It can only be used for behaviors that are the target of a Change Behavior action. For instance, suppose Behavior A has the following actions:

1. Goto RoomA
2. Change Behavior <Behavior B>
3. Exit <any>

And Behavior B has the following actions:

1. Wait 20 s
2. Resume prior

The Resume Prior Behavior action will cause the occupant to follow this sequence of actions:

1. Goto RoomA (from Behavior A)
2. Wait 20 s (from Behavior B)
3. Exit <any> (from Behavior A)

To add a Resume Prior Behavior action:

1. Click Resume Prior Behavior from the behavior actions list.

5.3.3.13. The Remove Occupant Action

Removes the occupant from the simulation. The occupant will no longer be visible or interact with any other remaining occupants.

To add a Remove Occupant action:

1. Click Remove Occupant from the behavior actions list.

5.3.3.14. The Wait Until Simulation End Action

The occupant will wait in their current location until all other occupants finish their behavior actions or also start a Wait Until Simulation End action. The manner in which the occupant waits is similar to the Wait and Wait Until actions.

To add a Wait Until Simulation End action:

1. Click Wait Until Simulation End from the behavior actions list.

5.3.3.15. The Goto Refuge Rooms Action

This action instructs the occupant to go to one of a set of rooms marked as refuge areas as discussed in Section 3.2.5. Like the Goto Exits action, this action must be the last action in the behavior. When an occupant reaches the refuge area, they will remain in the simulation and wait for the simulation to complete. Their behavior while waiting is described in the Wait action above. Additionally, the occupant will be tagged with "refuge_reached", as reported in the Occupants Summary and Occupant History output files as discussed in Section 14.7 and Section 14.8.

This action is created similarly to the Goto Rooms action, except that only rooms marked as refuge areas may be chosen.

5.3.3.16. The Goto Exits Action

This action causes an agent to take the fastest route to a set of exits. Like the Goto Refuge Rooms action, this action must be last in the behavior. Once an agent goes through an exit, they are removed from the simulation and reported as having exited the model in the Occupants Summary and Occupant History output files as discussed in Section 14.7 and Section 14.8.

To add a Goto Exits action:

1. Click Goto Exits from the behavior actions list.
2. Either click the Exits link to specify the desired exits with a dialog (see Section 2.6.1 for help using the Object Sets dialog), or left-click the desired exits in the 3D or 2D View.
3. Right-click in the 3D/2D View to finish selecting the exits and create the action, or click Create.

5.4. Generating Occupants

Occupants can be added to the simulation in a number of ways. The simulation can either be pre-seeded with any number of occupants or it can have occupants continuously generated by occupant sources. When pre-seeding the model, occupants can be placed individually in the 3D or 2D view, distributed in a rectangular region of a particular room, or distributed throughout the entire area of a room.

5.4.1. Individual Placement

Individual occupants can be added to the model with the Add Occupant tool . Occupants can only be placed in pre-existing rooms, stairs, and ramps and cannot overlap other occupants or room boundaries. Left-click a desired position with the mouse, or enter an x-y-z coordinate and press the Create button from the property panel to place an occupant (Figure 102).

5.4.2. Group Placement

Groups of occupants can be added to the model with the Add Occupant Group tool . The occupants are distributed throughout this region using parameters in the property panel as shown in Figure 105.

Once the properties have been specified, click-drag to draw the filling rectangle. Both points of the rectangle must lie in the same room (Figure 103). When you release the mouse button, the occupants will be placed within the designated region (Figure 104).

When an occupant is selected, the property panel allows the occupant’s name, profile, and behavior to be edited. All profile parameters are also displayed, showing exactly what value will be used for that specific occupant. Any of these parameters can be overridden by checking the box next it and entering the desired value. See Section 5.1.9 for more information.

5.4.2.1. Random or Uniform Placement

Random placement places occupants randomly within the designated area, such that no overlapping of occupants occurs. If the number of desired occupants is too great to accomplish this, a prompt will ask whether or not to continue with overlapping occupants. Uniform placement places occupants in an orderly hex pattern, allowing greater occupant densities before overlap occurs. Again, a prompt will ask whether to continue with overlap if the density is too great.

5.4.2.2. Count or Density

This option specifies whether to place a set number of occupants or place enough occupants to achieve a certain density. Several template densities are provided, and Custom can be selected from the densities drop-down menu to enter a new value.

5.4.2.3. Profile

This option allows a distribution of profiles to be set for the occupants, such as specifying that 25% of the added occupants should be females < 30 years old, 30% children, etc. The label shows the currently set distribution, and if there is more than one profile defined in the model, the value can be clicked to edit the distribution. See Section 2.6.2 for help specifying distributions.

5.4.2.4. Behavior

This option allows the distribution of behaviors to be set and is set by specifying percentages of each behavior.

5.4.3. Room Placement

In addition to distributing occupants in placement regions, occupants can be distributed throughout entire rooms.

To do this:

1. Select the desired rooms and choose Add Occupants from the Model menu or the right-click menu as shown in Figure 106. This will bring up the Add Occupants dialog (Figure 107). For an explanation of the dialog’s options, please see Section 5.4.2.
2. Click the OK button after selecting the desired options to place occupants and exit the dialog.

5.4.4. Occupant Sources

Occupant sources define areas in which occupants are generated dynamically throughout the simulation.

To add an occupant source, use the Add Occupant Source tool or right click on a door or a room in the model, and select Add Occupant Source If an occupant source that is attached to a component is later deleted from the model the user will be notified and the occupant source will either be attached to a different component or deleted.

There are three options for specifying the physical location of the occupant source within the model, as shown in Figure 108.

An occupant source can be defined by a rectangular region or attached to a component in the model.

From Rectangle

Use this option to draw a box that defines a placement region. This region is intersected with the navigation mesh, and new occupants are created at random positions in the intersected areas.

From Door

Use this option to attach the new occupant source to an existing door. The door can be selected either from the drop-down menu or by clicking on the component in the model. New occupants will be created at random positions along the door.

• If the door is one-way, the occupants will be placed slightly off of the door toward the one-way direction.
• If the door is an exit, the occupants are placed slightly inside the model.
• If the door is attached to an elevator, occupants are placed slightly outside the elevator.

From Room

Use this option to attach the new occupant source to an existing room. The room can be selected either from the drop-down menu or by clicking on the component in the model. New occupants will be created at random positions inside the room.

5.4.4.1. Parameters of an Occupant Source

Once the location of an occupant sources is defined, additional parameters that relate to the occupants that are generated can be specified. Figure 109 below shows parameters that can be specified for an existing occupant source.

Flow Rate

Rate in persons per second at which new occupants will be created (Section 5.4.4.1.1).

Enforce Flow Rate

Specifies whether the occupant source should keep generating occupants regardless of how crowded its area is (Section 5.4.4.1.2).

Profile

Specifies a profile distribution. See Section 2.6.2 for help specifying distributions.

Behavior

Specifies a behavior distribution.

Component

Shows which door or room the occupant source is attached to, if any.

Movement Group Template

Specifies the distribution of movement groups for occupants that are part of a movement group. An Ungrouped option is available for occupants that will not be part of any movement group. (See Section 8.4)

5.4.4.1.1. Flow Rate

The rate, in persons per second, at which new occupants will be created. The flow rate can be either constant or specified as a function from a table. The flow rate table editor is shown in Figure 111 below. The editor can also be used to automatically construct a periodical step function. To do so, click the Step function button. The Step Function dialog is shown in Figure 110 below. The editor with a generated step function is shown in Figure 111 below.

The following are the parameters of the step function that can be set in the Create Step Function dialog:

Flow Rate

Flow rate value when occupant generation is ON.

Initial Delay

The amount of time at the beginning of the simulation until the step function begins.

On Duration

Amount of time in each period for which occupant generation is turned ON.

Off Duration

Amount of time in each period for which occupant generation is turned OFF.

Number of Cycles

The number of ON/OFF pairs in which occupants are generated. After this, the occupant source will stop generating occupants.

5.4.4.1.2. Enforce Flow Rate

When Yes is selected, the occupant source will keep generating occupants regardless of how crowded its area is, which can result in overlapping occupants. When No is selected, the occupant source will only generate an occupant if the new occupant will not overlap with another occupant. Otherwise, the occupant source will wait until the next time step to try to generate an occupant again.

5.5. Redistributing Profiles and Behaviors

Once occupants have been created, the distribution of profiles and behaviors can be reshuffled among them.

5.6. Randomizing Occupants' Positions

After occupants have been created, their positions can be changed to new random positions.

To randomize occupants' positions, select one or multiple rooms, and from the right-click menu select Randomize Occupants' Positions The Randomize Occupants' Positions dialog appears (Figure 113), providing the option to change room and position settings.

After clicking OK, all occupants in the selected rooms will be moved to their newly generated positions. Occupants' orientation will change too, unless it is defined locally for specific occupants or set to a constant angle in the occupants' profile.

5.7. Reducing Population

It is sometimes necessary to reduce the number of occupants in the model. The number of occupants can be decreased in each room, stair, ramp, or occupant group automatically.

To reduce the number of occupants in a component or in an occupant group, right click on the specific object and select Reduce Population A dialog will appear with the option to set the new occupant count. The deletion method can also be set.

Pathfinder can either keep random occupants, first occupants in the selection, or last occupants in the selection.

6.1. Services

Services are the destinations of a Queue, defined by a point on the navigation mesh. When an occupant reaches one, they will wait at this point and then be released to their next behavior action; associated parameters designate the time for the occupant to wait before the queue releases them.

6.2. Paths

Paths are the routes of a Queue that occupants follow and wait at to reach a service. They are linear sets of Nodes on the navigation mesh, and occupants will form a line along the path between the nodes, moving forward to the exit end of the path and to the service when they are able.

Once created, paths have the following parameters:

6.3. Path Nodes

A path’s Nodes are the points in space that defines the route. The points are ordered from top to bottom in the tree, representing the nodes by distance from a service. They may be shuffled around or deleted in any order once created. Additional Nodes may be added to or deleted from a path after the initial path is created. Path Nodes can be moved to modify the path through the model.

7.1. Assistance Process Overview

Technical details of the algorithm for assisted evacuation are available in the Pathfinder Technical Reference (Pathfinder Resources), but a summary from both the assistants' and the clients' perspectives are given here.

7.2. Preparing Clients

There are some considerations to take into account when preparing clients. Table 9 outlines some important client-specific parameters that can help achieve a variety of evacuation outcomes.

Preparing occupants who can become clients can be done as follows:

7.3. Preparing Assistants

Preparing occupants who can become assistants can be done as follows:

7.4. Preparing Teams

Any number of assisted evacuation teams may be created. Assistants join teams through their behaviors and clients ask for assistance from teams through their behaviors. By default, assistants join the default team.

Assistants may only be a member of one team at a time, but they may be a member of several teams during the course of the simulation. This is accomplished by using an Assist Occupants action for each team in the assistant’s behavior.

To edit assisted evacuation teams, on the Model menu, click Edit Assisted Evacuation Teams (see Figure 115)

On the Priority tab, Client Priority controls the order in which clients are evacuated by a team.

The priority can be specified as follows:

The Assistants tab is read-only and shows all assistants who currently have a behavior that joins the team with an Assist Occupants action at some point in the simulation. You must use an Assist Occupants action to add an assistant to this list.

The Clients tab is read-only and shows all clients who currently have a behavior that requests assistance from the team with a Wait for Assistance action at some point in the simulation. You must use a Wait for Assistance action to add a client to this list.

8.1. Grouped Movement

Grouped movement is controlled by two concepts: connected state and the group leader. If a group is in a "disconnected" state, occupants will walk toward the leader. If a group is in a "connected" state, occupants move toward the goal dictated by their behavior. This framework allows groups that have become broken up to re-form and avoids imposing to harsh movement restrictions related to divided doors and other minor navigational differences.

The details of these behaviors are controlled by the following four parameters:

Smaller values for Maximum Distance and Slowdown Time give more cohesive groups and larger values give looser groups.

Group members share component restrictions (see Section 5.1.2). If a component is restricted for some group member, other group members will avoid the component as well.

8.2. Movement Groups

Movement Groups represent groupings of specific occupants that exist at the start of the simulation. They are listed in the Tree view within the Movement Groups node. They also appear in the property panel when selecting occupants belonging to the same Movement Group. Clicking the name of a Movement Group in the property panel will select it in the Tree view.

To create a Movement Group:

The new Movement Group will appear in the Tree view within the Movement Groups node. The Movement Group parameters (e.g. Maximum Distance) can be edited by selecting the Movement Group in the tree.

Manually creating individual Movement Groups is likely only necessary for special cases. Movement Group Templates offer a way to automatically create Movement Groups.

8.3. Movement Group Templates

Rather than describing a specific set of occupants that will move together, Movement Group Templates describe a kind of Movement Group. An example might be "Families, with 1-2 adults and 1-3 children". Pathfinder can use these descriptions to automatically create large numbers of Movement Groups from selections of occupants or during the simulation.

In addition to the three movement parameters described earlier, Movement Group Templates require occupant profile-based creation parameters:

To create a Movement Group Template:

The new template will be added to the Tree view in the Movement Group Templates node. The created template can now be used to automatically create movement groups.

When Pathfinder uses Movement Group Templates to sort occupants into movement groups, the algorithm is controlled by the following parameters:

To create Movement Groups using a template:

The new movement groups will be added to the Navigation view in the Movement Groups node and the parameters of individual groups can be edited if required.

When using the New Movement Group(s) from Template action, it is important to note that occupant profiles will be reset by the operation.

8.4. Adding Grouped Occupants from Occupant Sources

Sources insert occupants into the model while the simulation is running. By default, sources do not use groupings when adding occupants. Movement Group Templates can also be used to create movement groups dynamically as occupants are added to the simulation from sources. Sources can create grouped occupants using the following parameter:

To configure an occupant source to add grouped occupants:

The source will now insert grouped occupants based on the template settings.

9.1. Attractor Behavior

Attractors can change an occupant’s behavior to a simple built-in behavior that waits at the attractor for a limited time, or it can change the behavior to any other defined in the model. The occupant’s behavior can be changed permanently if the attractor behavior ends with a terminal action, such as Goto Exits. Alternatively, the attractor can temporarily interrupt the occupant’s current action if the attractor behavior ends with a Resume Prior Behavior action. In this mode, the behavior action that was interrupted by the temporary attractor behavior will be resumed when the attractor behavior is completed. For instance, if the occupant is using a Goto Rooms action and is interrupted by an attractor before they reach one of the rooms, the occupant will perform the attractor behavior and then resume the Goto Rooms action when the attractor behavior is complete.

9.2. Interrupted Waiting

The Wait and Wait Until actions operate in a specific way when interrupted by a temporary attractor. When either of these actions is started by an occupant, an ending time is calculated and never changes, even if interrupted. For instance, if an occupant starts a Wait action at t=63 s, and they decide to wait for 30 s, the calculated end time is t=93 s. If the occupant is interrupted by a temporary attractor while waiting, they will complete the attractor behavior and then resume the wait action. When they resume the wait action, however, the end wait time remains unchanged at t=93 s. If the current time is already past t=93 s, the occupant will immediately begin their next behavior action. Otherwise, they will wait until t=93 s before beginning the next action as usual.

In addition, whenever an occupant is interrupted by a temporary attractor while waiting, the occupant will return to their previous waiting area when they resume the wait action. For instance, if an occupant is directed to go to a room using a Goto Rooms action and then told to wait for some time, their waiting area will be the entire room they reached before waiting. If they are then interrupted by a temporary attractor while waiting, they will return to the waiting room when done with the attractor behavior. Similarly, if they had gone to a waypoint instead, they would return to the waypoint. When the occupant resumes the wait action, the time it takes to get back to the waiting area counts against the wait time. So if the wait time elapses while they are on their way back to the waiting area, the occupant will stop travelling to the wait area and begin their next behavior action.

9.3. Seeking vs. Waiting Interruption

Occupants are interrupted differently depending on whether they are seeking or waiting.

When seeking, as soon as an occupant becomes aware of an attractor, they will calculate a probability of using the attractor. If they decide to use the attractor, they will use it immediately. If they decide not to use it, they will remember that decision for as long as they are aware of the attractor. Once they become unaware again, they will forget the decision. This allows them to give the attractor another chance if they become aware of the attractor again later.

When waiting, as soon as the occupant becomes aware of an attractor, they will calculate a probability of using the attractor. If they decide to use the attractor, instead of using it immediately, they will schedule a random time during their wait period at which to use the attractor. If they do not know how long they will be waiting, such as when using the Wait Until Simulation End action, they will use the Default Attractor Idle Time property as their wait period. This property is defined in the Simulation Properties dialog under the Miscellaneous Parameters tab. As when seeking, if the occupant decides not to use the attractor, they will remember the decision until they become unaware of the attractor.

9.4. Creating Attractors

To create an attractor, perform the following steps:

9.5. Attractor Properties

The following properties can be set for an attractor in the property panel, either during creation or when an attractor is selected:

9.6. Attractor Limitations

While attractors work with most behaviors and for most occupants, there are some limitations, including the following:

10.1. Creating a View

To create a view, follow these steps:

A new view will appear in the Navigation View as shown in Figure 116.

10.2. Recalling a View

To recall a view, perform any of the following:

This will show the 3D View and the perspective camera will be initialized with the state of the saved view.

10.3. Editing a View

If the orientation of a view needs to be changed, perform the following:

Alternatively, the graphical representation of the camera can be manipulated to move the location of the view as discussed in Section 11.2.

10.4. Views in the Results

In order for the views created in Pathfinder to be available in the Results, a special views file is written to the output folder whenever the simulation is run. When the Results application is opened, it then reads the views from this file and makes them available in the Results.

Because this file is only automatically written when the simulation is run, however, a view can be changed in Pathfinder after running the simulation, making it out of sync with the views in the Results. In order to synchronize the views in Pathfinder and the Results without re-running the simulation, the views file must be manually written. To do so, follow these steps:

10.5. Camera Tours

In previous versions of Pathfinder, tours could also be created inside Pathfinder. This functionality was later moved to the 3D Results. Tours made in previous versions of Pathfinder, however, will still appear in the Navigation View of Pathfinder. While they can no longer be edited within Pathfinder, they can still be deleted. Ones that are not deleted will be written to the Results views file so that they are available in the Results.

11.1. Transforming and Copying Objects

All geometric objects can be transformed and/or copied. All transform/copy options are available through tools in the 3D and 2D views. The following transforms are available and are discussed in the following sections: moving, rotating, and mirroring.

11.1.1. Moving

To move one or more objects, select the objects and click the move tool from the 2D or 3D view. The property panel for the move tool is shown in Figure 117.

The object can be moved either manually or graphically:

Manually

Select Normal Mode and enter the distance to offset the object in the Move X, Y, and Z boxes. Then click Move.

Graphically

This is performed most easily in one of the 2D views. To translate graphically click two points on the model. The vector from the first point to the second defines the movement offset. When moving graphically, objects will only be moved parallel to the camera’s view plane.

Objects can also be copied using the move tool. To do so, select the move tool, select Copy Mode from the property panel, and follow the same steps as above for moving an object. Alternatively, hold CTRL on the keyboard while defining the offset. This will create a copy of the object that has been offset by the move distance.

Similarly, an array of objects can be made by specifying a value greater than 1 for the Copies field in the property panel. The array is created by offsetting each previous copy by the move distance. If, when copying rooms, the resulting copies overlap one another the most recent copies take precedence over earlier ones, meaning that earlier ones will have area subtracted from them.

11.1.2. Rotating

To rotate one or more objects, select the objects and click the rotate tool from the 2D or 3D view. The property panel for the rotate tool is shown in Figure 120.

The object can be rotated either manually or graphically:

Manually

Select Normal Mode and enter the base of rotation, the axis about which to rotate using the right-hand rule, and the angle to rotate. Then click Rotate.

Graphically

This is performed most easily in one of the 2D views. The rotate axis is automatically set to a vector normal to the camera. Rotating requires three mouse clicks.

• The first specifies the base of rotation (Figure 121).
• The second defines a reference vector extending from the rotation base (Figure 122).
• The third defines a second vector extending from the rotation base (Figure 123). The rotation angle is the angle between these two vectors.

Objects can also be copied using the rotate tool.

1. Select the rotate tool
2. Select Copy Mode from the property panel, and follow the same steps as above for rotating an object. Alternatively, hold CTRL on the keyboard while defining the rotate properties.

This will create a copy of the object that has been rotated from the original using the rotate parameters. Similarly, an array of objects can be made by specifying a value greater than 1 for the Copies field in the property panel. The array is created by rotating each previous copy by the rotate angle.

If copying rooms and resulting copies overlap one another the most recent copies take precedence over earlier ones, meaning that earlier ones will have area subtracted from them. An array is shown in Figure 125.

Creating an array of objects using the rotate tool

11.1.3. Mirroring

To mirror one or more objects about a plane, select the objects and click the mirror tool from the 2D or 3D view. The property panel for the mirror tool is shown in Figure 126.

The object can be mirrored either manually or graphically:

Manually

Select Normal Mode and enter the plane about which to mirror. This can be an axis-aligned plane or a custom plane specified by the plane equation, \(ax + by + cy + d = 0\). Next click Mirror.

Graphically

This is performed most easily in one of the 2D views. The mirror plane is always perpendicular to the camera’s view plane. Defining the plane requires two mouse clicks that define two points in the plane. The steps for mirroring graphically are shown in Figure 128.

Mirroring an object

Objects can also be copied using the mirror tool. To do so, select the mirror tool, select Copy Mode from the property panel, and follow the same steps as above for mirroring an object. Alternatively, hold CTRL on the keyboard while defining the mirror plane. This will create a copy of the object that has been mirrored from the original using the mirror plane.

11.2. Manipulating Objects with Handles

Some objects, including occupants, rooms, stairs, and doors, can be edited through manipulator handles. Handles act as points on an object that can either be dragged with the selection tool or edited by the keyboard to edit the attached object. Handles only appear on selected objects and show as blue dots as shown in Figure 129.

11.2.1. Selecting and Deselecting a Handle

To select an object’s handle, the object itself must first be selected. Once it is selected, the blue handles should appear. Next select the Select/Edit tool . Now an individual handle can be selected by clicking it, which will make the handle property panel appear as shown in Figure 130. To deselect the handle, press ESC on the keyboard, click anywhere else in the model, or select another object.

11.2.4. Thin Door Handles

When a thin door is selected, three handles will be displayed as shown in Figure 131. The handles on the ends of the door allow the door to be moved along the edge to which it is attached. The middle handle allows the door to be made thick by moving the handle to the edge of another room as shown in Figure 132.

11.2.6. Stair and Ramp Handles

When a stair or ramp is selected, six handles will be displayed as shown in Figure 133. The four corner handles each allow the stair/ramp to be moved along the edge to which the handle is attached. The middle handles allow the stair/ramp to be reconnected to another room. The middle handles can also be useful if the geometry of one room attached to a stair/ramp has changed in such a way that the stair/ramp is no longer attached to the room. The middle handle can be used in this case to reconnect to the room.

11.2.7. Occupant handle

When an occupant is selected, there is only one handle as shown in Figure 134. The sole purpose of this handle is to move the agent to another location. Moving an agent in this manner has a benefit over the translation tool in that the location automatically snaps to an existing room or stair as when adding an agent using the agent dropper tool.

11.2.8. Waypoint Handles

When a waypoint is selected, two handles are displayed as shown in Figure 135. The center handle allows the waypoint to be moved to another location similarly to the occupant handle. The perimeter of the circle can be used as a handle to change the arrival radius of the waypoint.

11.3. Enabling and Disabling Objects

Several objects in Pathfinder can be enabled or disabled. Disabling an object removes the object from the model. A disabled object does not appear in the simulation. Following objects can be enabled and disabled in Pathfinder:

To enable or disable an object, right click on the object in the 3D view or in the navigation tree and select Enable or Disable. Disabled objects are invisible in the 3D view. In the navigation tree, disabled objects are greyed out and crossed out.

12.1. Measurement Regions

Measurement regions cause the simulator to output time history data for velocity and density within a specific region on the navigation mesh. See Section 14.4 for information about Measurment Region results.

Measurement regions can be created using the Add a Measurement Region tool .

Adding one or more density regions will cause the simulator to output a CSV file named filename_measurement-regions.csv containing data for each density region. The data in this file can be used to plot fundamental diagrams in the measurement area.

Output frequency for measurement region CSV data is controlled by the CSV Output Freq. parameter on the Output tab of the Simulation Parameters dialog.

To ensure accurate results, measurement regions must:

Essentially, measurement regions should be placed on open space that will be used by occupants. Ideally, the measurement region should not be larger than the area where the steady flow under study occurs. If the measurement region is too large, results might indicate a lower value than expected because the quantity is integrated over the entire region.

For additional information about measurement regions, please refer to the Pathfinder Technical Reference.

12.2. Measuring Distances

Distances can be measured by using the measuring tool .

To do so, select the measuring tool from the 3D or 2D view. To measure distance along a sequence of points, left-click each point. After each point in the path has been specified, right-click to display the cumulative point-to-point distance in a dialog box.

When measuring distances in the 3D view, the distance is taken as the actual distance between snapped points. When measuring distances in the 2D view, however, the distance is taken by projecting the points onto a plane parallel to the camera view plane, and then taking the distance.

13.1. Parameters

The Simulation Parameters dialog provides a way to control certain features of the simulation, as well as provide some default values.

13.1.1. Time Parameters

The Time tab (Figure 137) provides the following options:

Time Limit

Can be used to automatically stop the simulation after a set simulation time.

Time Step Size

Controls the resolution of simulation time steps. Increase the time step size to speed up simulations, reduce the time step size to ensure simulation accuracy.

13.1.2. Output Parameters

The Output tab (Figure 138) provides the following options:

3D Output Freq

controls the time between 3D output file updates. Increasing this value causes data to be written less often, leading to less disk usage and run faster simulations (no file write delay), but can produce a misleading 3D results visualization. In the 3D results visualization, occupants will move in a straight line between two data points - if the two points are far apart in time, an occupant might appear to pass through an obstruction when it actually navigated properly.

CSV Output Freq

controls the time between CSV output file updates. Increasing the value causes fewer rows to appear in the resulting CSV files (i.e. lower data resolution). This option has a negligible effect on simulation performance or disk usage, but can affect performance in the 2D results.

Runtime Output Freq

controls the time between simulation status updates in the Run Simulation dialog. This option has a negligible effect on simulation performance or disk usage.

Jam Velocity

controls the speed threshold at which occupants are recorded as being jammed in the Occupants output file.

Occupant CSV Data

controls how the CSV data is generated for occupants with Print CSV Data enabled. See Section 14.8 for more information.

Merge into one file

All occupants with CSV data enabled are written to the same file. The file is named filename_occupants_detailed.csv, where filename is the name of the saved PTH file without the .pth extension.

Create one file per occupant

Each occupant with CSV data enabled is written to a different file. The file is named, filename_occupant_id_occname.csv, where filename is the name of the saved PTH file without the .pth extension, id is the integer id of the occupant assigned by the simulator, and occname is the name of the occupant specified in the user interface.

Include Seek Speed in Measurement Region Files

controls whether to include an additional column in the measurement region files called "SeekVelocity", which indicates how fast an occupant is moving relative to the direction of their goal. For instance, if an occupant wants to move in the +X direction, and they are moving in the +X direction at 1.2 m/s, this column will show 1.2 m/s; however, if they instead move in the +Y direction, this will become 0 m/s because they are not moving toward their goal. NOTE: This value is always >= 0, even if the occupant is moving backward away from their goal.

Write Occupant Parameter File

Indicates whether to write the Occupant Parameters file. See Section 14.5 for more information.

Enable Interpersonal Distance Reporting

Enabling this feature will cause the simulator to create two output files: filename_sd_transient.csv and filename_sd_accumulated.csv. These files report interpersonal distancing information based how close together occupants are located. The distance calculation is computationally expensive and adds about 10% to simulation runtime. See Section 14.6 for more information.

Reference Distance

When interpersonal distance reporting is enabled, this value is used to calculate exposure data and is reported as SD in filename_sd_accumulated.csv. See Section 14.6 for more information.

13.1.3. Paths Parameters

The Paths tab (Figure 139) contains properties that control how occupant paths are generated and how the navigation mesh is triangulated. Generally, these settings should not be changed.

Max Agent Radius Trim Error

This parameter affects how accurately occupants can navigate through tight spaces when the occupants in the simulation have varying sizes. The larger this value is the less likely an occupant is to navigate through a space that has a width close to their body diameter. With larger values, however, the simulation will consume less memory and start faster (sometimes much faster if every occupant has a different size). Each occupant is guaranteed to be able to fit through a space with width equal to the occupant’s diameter plus twice this value.

Navigation Mesh Refinement

Controls whether and how finely the navigation mesh is refined into smaller triangles. The following values are allowed:

None

Disables mesh refinement. This is the default option and provides the best performance. It allows Pathfinder to generate the fewest and largest possible triangles, which works well in most cases with Pathfinder’s search algorithms.

Constrain triangle area

Specifies an upper bound on the area of the triangles in the navigation mesh. In some situations, smaller triangles can be useful for more accurately determining shortest distance, which may fix issues where occupants are taking long paths. Smaller values result in more triangles, which can significantly impact simulation performance, increasing the time to simulate with more triangles.

Constrain Edge Length

Similar to Constrain triangle area, this results in smaller triangles, which may in some cases fix issues where occupants are taking long paths.

Max Edge Length

Controls the maximum length of any single edge on a room boundary.

Min Angle

Sets a lower bound on the angle between adjacent triangle edges. Larger values increase the quality of the triangles, preventing long, thin triangles, but values greater than 30 degrees can cause Pathfinder to "freeze" when it attempts to generate a simulation input file.

13.1.4. Behavior Parameters

The Behavior tab allows you to set options for Pathfinder’s two primary simulation modes: SFPE and Steering. To select a simulation mode, choose SFPE or Steering from the Behavior Mode drop-down box.

13.1.4.1. SFPE Mode Parameters

The SFPE mode uses the set of assumptions presented in the Engineering Guide to Human Behavior in Fire (SFPE 2019) and can give answers extremely similar to these hand calculations, depending on selected assumptions. In SFPE simulations, the mechanism that controls simulation movement is the door queue. The SFPE mode uses a simple set of assumptions and usually completes much faster than a comparable steering mode simulation in terms of CPU time.

The SFPE mode supports the following options:

Max Room Density

Controls the density at which doors will no longer admit occupants into a room. Using an artificially low value for this number will give faster evacuation times. Using a higher number 3.6 - 3.8 can cause extremely slow evacuation times. Using values above 3.8 pers/m2 can cause the simulation to become stuck due to the density dependent velocity calculation.

Door Flow Rate→Boundary Layer

This value is subtracted from both sides of a door to calculate the effective door width, controlling the flow rate equation. For example, with a Boundary Layer setting of 150 mm, a 1.0 m door would be reduced to a 0.7 m opening giving an \(F_\text{s_max}\) of (1.32 pers/s-m * 0.7 m) = 0.924 pers/s.

Door Flow Rate→Flow Rates at High Density

controls how specific flow for doors is calculated. Specific flow is a measure of occupants per unit of time per unit of effective width. For each door, the specific flow is multiplied by the effective door width to calculate the door flow rate in occupants per unit of time.

Use a Calculated Specific Flow

Specific flow is calculated as a function of room density for a room adjacent to the door. In cases of counterflow, the room with the higher density controls the combined specific flow of the door.

Always Use Max Specific Flow

Allows the door to flow at the optimum density. Minimum Speed Fraction* can be used to set a lower limit on occupant speed. Setting this value too low can cause evacuation times to increase significantly in cases of high initial loading of rooms or if the Max Room Density is set very high.

13.1.4.2. Steering Mode Parameters

The Steering mode is more dependent on collision avoidance and occupant interaction for the final answer and often gives answers more similar to experimental data than the SFPE mode (i.e. steering mode often reports faster evacuation times). Door queues are not explicitly used in Steering mode, though they do form naturally.

The Steering mode supports the following options:

Steering update interval

Specifies how often (in simulation time) to update the steering calculation. This could also be considered to be the cognitive response time of each occupant. The higher this number, the faster the simulation will run, as long as the simulation time step is less, but the poorer the decision making skills of each occupant will be.

Minimum flowrate factor

This is used when agents are deciding which doors to use when there are queues at the doors. The factor is multiplied by the door’s nominal flowrate to determine a minimum observed flowrate. A non-zero factor will cause a door to always appear to be flowing even if it is not. This helps prevents occupants from excessively switching doors when flowrates are very low; however, it can also cause occupants to stick with the same door even if it cannot flow any more, such as a door into a refuge room that has filled completely near the door. If occupants are refusing to leave a blocked door into a room when other doors are available, try setting this parameter to 0.

Collision Handling

Controls whether occupants avoid one another and can collide with each other.

Enable Forced Separation

When enabled, this will cause occupants to attempt to always strictly maintain their Personal Distance (Section 5.1.6). When disabled, Personal Distance will only apply while queueing.

Limit Door Flow Rate

When checked, this imposes a maximum flow rate on doors unless they have it explicitly turned off (Section 3.4.3). The flow rate for each door is calculated from the Boundary Layer and Specific Flow, similarly to SFPE Mode. The difference between Steering and SFPE Modes is that Steering does not allow flow rates to be based off room density.

13.1.5. Miscellaneous Parameters

The Miscellaneous tab (Figure 142) provides rarely-changed options, including the following:

Show Runtime Visualization

Whether to enable the debug view when running a simulation. This has the same effect as starting a simulation using Simulation→Debug Simulation.

Save Restart Files

Whether to save a restart file while the simulation is running. Enabling this option will cause a snapshot of the simulation to be saved periodically to the restart file while the simulation is running. This is useful for debugging or if the computer loses power while running a simulation, as the simulation can be resumed from any of the saved snapshots by using Simulation→Resume Simulation.

Snapshot Interval

Defines how often to save snapshots to the restart file in simulation time (not to be confused with wall-clock time).

Curve error

Controls how imported curved CAD lines are turned into multi-segmented lines for use in floor extraction and for display purposes. Smaller error values result in more segments.

Face error

Controls how imported curved CAD faces are turned into triangles for use in floor extraction and for display purposes. Smaller error values result in more triangles.

Default Attractor Idle Time

When an occupant chooses to use an attractor while waiting an indeterminate amount of time, this property defines the period in which the occupant will schedule the attractor. See Section 9.3 for more information.

Enable visualized sideways movement of vehicles

Allows vehicles to appear as if they are moving sideways rather than turning as they move. Enabling this option only changes the visualization and not the simulation of how vehicles move. If this option is enabled, the vehicle shape must also have the Allow sideways movement option checked.

13.2. Starting and Managing a Simulation

To run a simulation: on the Model menu, click Run Simulation . The simulation will begin and the Run Simulation dialog (shown in Figure 143) will appear.

In this dialog, the abbreviation DTG stands for distance to goal. The maximum distance to goal represents distance to goal for the occupant farthest from its goal. The average distance to goal is the average of all occupants' distances to their respective goals.

The Debug button launches a runtime visualization that shows the progress of the simulation as it is taking place. This function is different from the Results button which launches the 3D visualization view for simulation results.

A simulation can also be paused, resumed, and cancelled at any time.

13.3. Stopping and Resuming a Simulation

When running a simulation, there is the option to pause and resume, but this requires Pathfinder to be running the entire time. Sometimes the need arises to be able to stop a simulation and resume later between Pathfinder sessions, such as if the computer needs to be restarted after installing a system update.

To stop a simulation:

To resume the simulation at a later time:

14.1. Summary Report

The summary report file contains information about the simulation geometry, simulation performance, statistics, and usage information for each room, stairway, and door.

Figure 144 shows a portion of an example summary report file.

This file is saved in the simulation directory and given the name filename_summary.txt (where filename is the name of your saved PTH file). To view it, under the Results menu choose Show Summary File. The first section shows the mode the simulation was run in, the total number of occupants, and statistics on the completion times for the occupants. It also shows some information about the mesh, including the number of triangles and the doors. This information can be useful when considering the complexity of a simulation from the standpoint of the simulator.

Each statistic is generated by sampling quantities from the occupants as data points. Only occupants for whom the quantity is relevant are included in the statistic.

Statistics on the following quantities may be printed to the summary file:

Some statistics are further broken down by behavior and by profile. For occupants who used multiple behaviors and/or profiles due to Change Behavior or Change Profile behavior actions, they are reported according to the behavior or profile in use when they completed their actions.

The table at the end of the summary file gives a listing of each component (doors, rooms, and stairs) in the simulation. For each component, the FIRST IN column shows the simulation time when the first occupant entered that component. LAST OUT shows the simulation time when the last occupant exited that component. The TOTAL USE column shows how many times a component was entered by occupants. For doors that served more than 1 occupant, the FLOW AVG. column shows the result of dividing the total use by the amount of time the room was in use (LAST OUT - FIRST IN). Each component can be annotated with its group names (e.g. floors). This annotation can be set by selecting Include Group Names in Output in the File→Preferences dialog.

14.2. Door History

The door history file (filename_doors.csv, where filename is the name of your saved PTH file) provides results data for doors. Each row represents a different time step, and the columns are as follows:

This file is used to display door flow rate, specific flow, and usage history in Pathfinder.

14.2.1. Door Flow Rate and Specific Flow

To view door flow rate or specific flow, click View Door Flow Rates on the Results menu. This opens a time history plot for doors as in Figure 145. This plot shows data from the door history file.

In the left portion of the window is a list of the doors, and on the right is a graph of the data. For each door, the list on the left shows three rows: one for each of the two directions and one for total. The directional data can be hidden by unchecking Include Directional Data under the View menu. Each row in the list shows group names for each door (if the Include Group Names in Output option under File→Preferences was enabled in Pathfinder when the simulation was run). The group names can be hidden by unchecking Show Group Names under the View menu of the history plot dialog.

By default, door flow rates are shown. Alternatively, on the Mode menu, choose Specific Flow to view door specific flow.

There are three filtering modes for presenting the flow rate that are selectable through the View menu:

Raw

this provides raw flow rate, which is simply \(\frac{\text{num\_occs}}{dt}\), where \(num_occs\) is the number of occupants to pass through the door in an output time step, and \(dt\) is the output time step.

Low-pass Filter

the raw flow rate is filtered with a bi-quad low-pass filter with a user-specified cutoff frequency. This is the default filter, and the default cut-off frequency is .05 Hz. Lower cut-off frequencies produce smoother graphs.

Moving-average Filter

the raw flow rate is averaged over a user-specified period.

14.3. Room History

The room history file (filename_rooms.csv, where filename is the name of your saved PTH file) provides the following information columns in each row:

To display this data as a time history plot, click View Room Usage on the results menu. Similarly to door history, the list on the left shows group names for each room (if the Include Group Names in Output option under File→Preferences was enabled in Pathfinder when the simulation was run). The group names can be hidden by unchecking Show Group Names under the View menu of the history plot dialog.

14.4. Measurement Regions Graph

The measurement region file (filename_measurement-regions.csv, where filename is the name of your saved PTH file) provides the following information columns in each row:

To display this data as a time history and a speed vs density plot, click View Measurement Regions on the Results menu.

14.5. Occupant Parameters

The occupant parameters file (filename_occupant_params.csv, where filename is the name of your saved PTH file) provides a summary of the initial states of almost all parameters assigned to each occupant, such as maximum velocity, occupant radius, etc.

This is useful for verifying the parameter distributions as specified in the occupant profiles (see Section 5.1 and Section 5.1.7 for more information). This file is written by default but can be turned off in the Simulation Properties dialog (see Section 13.1.2).

In addition, any occupants that have customized parameters (Section 5.1.9) will invalidate the distributions. These customized occupants must be manually excluded from the analysis to determine resulting distributions.

14.6. Interpersonal Distance

The interpersonal distance output files (filename_sd_transient.csv and filename_sd_accumulated.csv) provide information related to how closly occupants are located throughout the simulation. Distances are reported as as measured center-to-center.

14.7. Occupants Summary

The occupants' summary file (filename_occupants.csv, where filename is the name of your saved PTH file) provides statistics about each occupant in the simulation. Each row of the CSV represents one occupant and provides the following:

14.8. Occupant History

For each occupant whose profile has CSV data output enabled (Section 5.1), additional time history data for the occupant is written to a CSV file.

Each row of the file contains the following data for the occupant:

For occupants with CSV output enabled, this data may optionally be written to one CSV output file or one file per occupant. This preference is controlled by the Occupant CSV Data option as described in Section 13.1.2.

14.9. Groups Output

The groups output file (filename_groups.csv, where filename is the name of your saved PTH file) provides information about groups that were created before and during the simulation.

14.10. Attractors History

The attractor history file (filename_attractors.csv, where filename is the name of your saved PTH file) provides time history data for each attractor in the model. Each row of the file contains a single time step with the following data for each attractor in the columns:

14.11. 3D Results

Included with Pathfinder is the Pathfinder Results Viewer for visualizing 3D results. This software can be used to visualize results from both Pathfinder and the Fire Dynamics Simulator (FDS) from the National Institute of Science and Technology (NIST).

By default, the Pathfinder Results Viewer starts automatically when a Pathfinder simulation has finished. To start the results viewer manually either click View 3D Results in main toolbar or in the Results menu click View 3D Results.

For more information on using the Pathfinder Results Viewer, refer to the (Pathfinder Results User Manual, n.d.).

15.1. Occupants cannot reach their goals, or they are getting stuck

Check the connectivity of the mesh. Check how various components are connected in the model to debug simulation errors or to ensure model validity.

To determine why a specific occupant cannot reach its next goal:

Pathfinder will highlight the entire graph of components touching the initial selection. We can then inspect the selected components to find out where they are disconnected from the occupant’s goal.

For finer inspection in a highly connected model, select only immediately adjacent components in the Select Connected Components dialog.

Sometimes occupants become "stuck" even on a properly connected mesh, preventing a proper simulation run. There can be many causes of this problem and we do everything we can to prevent it, but it does happen. If occupants are becoming stuck in tight spaces, consider the following steps to resolve the problem:

15.2. Warnings and errors in the navigation tree

Pathfinder shows warnings and errors in the Navigation Tree to help debug potential errors in the simulation. These warnings appear as a small exclamation mark imposed over an occupant or record, . By hovering the mouse over the warning, a more detailed description of the problem can be determined. For convenience, if an object has problems, the warning marker is propagated up through the navigation tree to its ancestor groups in order to quickly identify problems in the model.

Some common warnings include:

Problematic objects can be quickly selected by right clicking a group in the tree that has a warning or error icon, and selecting either Select Errors or Select Warnings from the right-click menu. In addition, if the warning on a component indicates that it interferes or overlaps with other components, the objects with which it interferes can be quickly selecting by right-clicking the object with the warning and selecting Select conflicting components from the right-click menu.

As a general note, if the warning "Edge is adjacent to more than 2 triangles" appears when simulating, an option to click Cancel appears to highlight the navigation components causing the warning.

15.3. Find objects related to a specific object

In Pathfinder, there are several objects that can refer to other objects in the model. For instance, an occupant can refer to both a profile and a behavior, a behavior can refer to exits, the goto elevators action can refer to elevators, etc. There are times when it is useful to know what objects are referring to another. For instance, it may be important to know which occupants are using a particular behavior. To do this, right click the behavior (or other in-use object), and from the right-click menu, click Select Referencing Objects. This will highlight all objects currently using that behavior.

15.4. System memory issues

Some models may require significant system memory to run, either because the navigational model is complex with many doors/connections, etc, or simply because there are tens of thousands of occupants. By default, Pathfinder will use up to half of system memory to run the user interface and the simulation. In some cases, this is not enough, which may result in Pathfinder crashing or the operating system becoming unresponsive while the simulation is running. In this case, it may be possible to allow Pathfinder to use more system memory. There are two ways to do this.

The first way is to run Pathfinder from the command line and specify an additional flag that indicates more memory should be allowed for Pathfinder. To do so:

For a more permanent way to specify a higher memory limit you can perform the following:

15.5. Issues with custom avatars

If you experience issues displaying a custom occupant or vehicle avatar, see Section 4.5.5 for help troubleshooting.

15.6. Video display problems and crashes on startup

Pathfinder utilizes many advanced graphics card features in order to provide accelerated and enhanced display of models.

Sometimes these graphics features combined with certain display drivers can cause display issues or crashes on startup. The first step in these cases is to ensure you have the latest operating system updates and graphics drivers installed. If you do and you still have display problems or crashing on startup, you can start Pathfinder in Safe Mode, which disables several graphics features. To start in Safe Mode:

If you encounter display problems or crashes, please let us know the make/model of your video card and what video driver you are using, even if Safe Mode fixes your issues. That will help us improve the software in future updates.

15.7. Additional support resources

Pathfinder has a support forum located at https://thunderheadeng.freshdesk.com/support/discussions.

If you are unable to resolve your issues from the suggestions in the table, please contact Thunderhead Engineering Email Support.

The Pathfinder software is available for download from the release notes: https://support.thunderheadeng.com/release-notes/pathfinder/

Mail should be sent to:

Thunderhead Engineering
403 Poyntz Ave. Suite B
Manhattan, KS 66502-6081
USA

A.1. Profiles from the IMO’s Revised Guidelines for Passenger Ships

The profile bundle imo_speed_profiles.plib is based on data from the IMO’s guidelines (IMO 2007).

This source gives ranges of walking speeds on flat terrain for each of 12 different population groups. This is implemented directly in the Pathfinder profiles as per-profile uniform distributions. The bundle of profiles in Pathfinder includes only the ten population groups that do not correspond to crew members.

A table is given for speed-density relation on flat terrain in terms of "initial specific flow" and a reference "initial speed". These two values were used to create a speed-density factor table shared by all profiles in this set.

The revised guidelines also define ranges of walking speeds up and down stairs for all population groups. Since Pathfinder requires a speed factor for stairs rather than a range, these values were approximated by calculating a constant scaling factor based on the average of the flat terrain range and the average of the range of speed on stairs.

A.2. Profiles from Fruin’s Pedestrian Planning and Design

The profile bundle fruin_speed_profiles.plib is based on data from John Fruin’s Pedestrian Planning and Design (Fruin and Strakosch 1987).

This source describes six population groups based on age and gender, and only gives a single normal distribution of walking speeds that is used for all population groups. This is implemented in Pathfinder by re-using the same normal distribution for the six population groups and an "Average All" aggregate profile.

The built-in SFPE-based speed-density relation is used for all profiles in this set. The built-in SFPE-based speed-density relation differs from the original data primarily in the locations where the min and max walking speeds are clamped. The original data was in terms of an absolute measurement of walking speed across multiple people rather than a value that could be normalized to a specific speed (1.2 m/s) and it went to zero at high densities which is undesirable for simulation because it could cause issues with occupants becoming permanently stuck. The following chart compares the original data to the relation used for this profile in Pathfinder.

Pedestrian Planning and Design (Fruin and Strakosch 1987) gives stairway speeds for two slopes, identified as an "indoor" 32 degree stair (7" / 11.25") and an "outdoor" 27 degree stair (6" / 12"). Speeds are given for the up direction and the down direction and they are individualized for the six population groups and the aggregate group. These speeds were converted to tables of speed modifier fractions. For each slope and direction, the speed on stairs was converted to a fraction of max speed by dividing by the average of the flat walking speed (1.2 m/s) used by all population groups. This made it possible to create tables of speed modifiers unique to each population group and travel direction that contained two data points. For stairs with slopes more or less than the given 32 and 27 degree stairs, the factor is constant (i.e. not extrapolated).

B.1. MESH Section

The MESH section of the BEA file links to the avatar file and describes any scaling and other transformation properties as follows:

MESH { "avatarfile" scale additional_transforms }

The scale factor is always the first transform applied to the avatar. All other transforms are applied in reverse order, meaning that the last listed transform is the first non-scale transform applied to the avatar.

Example:

MESH {"avatar.fbx" 2.0 translate 0 0 .1 rotate 0 0 1 90 rotate 1 0 0 180}

will first scale the avatar by 200%, then rotate it about the X axis by 180°, then rotate about the Z axis by 90°, and finally move it up along the Z axis by .1 m.

B.2. ANIMATIONS Section

The ANIMATIONS section is only used for occupant avatars. There are two categories of animations: IDLE and MOVE. Each category can have several animations types. Each animation type can list any number of animation files. Each animation file is listed with several parameters, depending on the category of the animation.

The animation types are as follows:

 MOVEFORWARD {
    "anims/walk1.md5anim" 13 .725 1.1 retarget_to "anims/base_mesh.md5mesh"
    "anims/walk3.md5anim" 5 1.800 1.7 retarget_to "anims/base_mesh.md5mesh"
    "anims/maleRun.md5anim"   4 3.170 1000 retarget_to "anims/base_mesh.md5mesh"
}