Flexible Movement Simulation

Pathfinder combines a powerful simulation engine with flexible control over population and behavior to deliver better results.

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Pathfinder is an emergency egress simulator that includes an integrated user interface and animated 3D results. Pathfinder allows you to evaluate evacuation models more quickly and produce more realistic graphics than with other simulators.

Robust Import Options

Pathfinder provides support for the import of AutoCAD format DXF and DWG files. Pathfinder’s floor extraction tool makes it possible to quickly use the imported geometry to define the occupant walking space for the evacuation model. PyroSim or Fire Dynamics Simulator (FDS) models can also be used to extract the walking space.

If you have a blueprint, it can be imported in GIF, JPG, or PNG format and then used as a background to help you rapidly draw your model directly over the image.

Imported DXF file

Continuous Movement Mesh

Pathfinder uses a 3D triangulated mesh to represent the model geometry. As a result, Pathfinder can accurately represent geometric details and curves.

Triangulation also facilitates continuous movement of persons throughout the model, compared to other simulators that subdivide the space into cells that can artificially constrain the movement of occupants.

Navigation Mesh

Multiple Simulation Modes

Pathfinder supports two simulation modes. In Steering mode, agents proceed independently to their goal, while avoiding other occupants and obstacles. Door flow rates are not specified but result from the interaction of occupants with each other and with boundaries. In SFPE mode, agents use behaviors that follow SFPE guidelines, with density-dependent walking speeds and flow limits to doors. SFPE results provide a useful baseline for comparison with other results, but SFPE calculations do not prevent multiple persons occupying the same space.

Optionally, Pathfinder allows you to specify door flow rates in steering mode to obtain superior visualization in a constrained model. You can freely switch between modes in the Pathfinder user interface.

Steering and SFPE Modes
Movement to Exit

Occupant Movement to Exits

By default, each occupant (agent) uses a combination of parameters to select their current path to an exit. The parameters include: queue times for each door of the current room, the time to travel to each door of the current room, the estimated time from each door to the exit, and the distance already traveled in the room. The agent responds dynamically to changing queues, door openings/closures, and changes in room speed constraints (simulating smoke and debris). The user can modify the default parameter weights to change the behavior. For example, occupants can neglect queues and only look for the closest exit.

Alternately, occupants can be assigned specific goals (such as, go to a location and wait) or specific exits. For example, most occupants of lower floors can be assigned to use stairs, while most occupants of higher floors can be assigned to use elevators.

Visualization

High-quality 3D Visualization

Pathfinder includes human models that represent a range of cultures, ages, attire, and emergency responders. These make it possible to realistically portray the population group of interest. Because we use a dynamic level-of-detail to display the models, Pathfinder can smoothly animate tens of thousands of people in real time using a standard graphics card.

Pathfinder also provides easy tools to create movies that document the results.

Movement Groups

Movement Groups

Connect families, coworkers, students, or other groups of occupants into groups that will seek each other and maintain a minimum distance apart. These groups can be formed with a leader profile for organized group evacuations or for non-evacuation purposes such as a tour guide through a museum. If one member is too far away, grouped occupants can become disconnected and will slow down to allow the disconnected member to catch up. In crowded environments, this effect is lessened as occupants realize the need to keep traffic moving.

Contour Plots

Easy to Understand Contour Plots

Contour plots can add data visualization overlays, such as occupant density, to the floor surfaces of your model for a quick and easy to understand view of simulation results. Smooth playback enables this information in real-time.

Available plots include density, usage, level of service and others. Each of these can be customized by modifying options such as the number of buckets, value ranges, color shading, and feathering.

Assisted Evacuation

Occupants with special mobility needs can be modelled with wheelchair and hospital beds to be evacuated by designated assistants. These models include full animation for realistic results. Separate evacuation teams can focus on assisting specific groups of individuals.

Create custom vehicles for more aided mobility possibilities. Vehicles have configurable vertices and assistant attachment points to create unique shapes physical properties.

Occupant Sources

Dynamically add occupants to a model based on a predetermined flow rate table. This functionality allows models to have sources of new occupants entering throughout various times, to simulate the incoming traffic flow from entrances outside of the simulated area.

Occupant Sources

Elevators

Pathfinder gives you the flexibility to evaluate evacuation options using elevators. Each elevator has a priority list of pickup floors and a discharge floor. People can move directly to the closest elevator or be directed to go to a refuge floor and wait until evacuated by elevator. Emergency responders can control selected elevators to carry them to desired locations.

A call to an elevator is initiated by a queue at the elevator door. Elevators can be grouped in banks to respond to calls.

Elevators

Stairways, Escalators, Moving Walkways, and Ramps

Stairways and ramps are created using simple mouse clicks on landings. Optionally, stairways and ramps can be used to represent escalators and moving walkways (sloped or flat).

Stairways

Customizable Populations

Each person in the model acts as an agent with their own profile (such as size and walking speed) and their own behavior (such as exits, waits, and waypoints). Based on their characteristics, each person uses their local environment to make decisions on exit paths. For example, people can dynamically avoid long queues or respond to the closure of doors.

Multiple profiles can be created and assigned to different populations. Parameters in each profile can be described using constant, uniform, standard normal, or log normal distributions. For example, profiles representing children and adults can be created and then the population can be assigned to be 80% adult and 20% children. Similarly, multiple different behaviors can be created and assigned to populations. People may have different exit goals and may proceed to waypoints or wait before proceeding. These behaviors can be designed to change over time.

Stairways

Fundamental Diagram Customization

By default, Pathfinder uses the fundamental diagram from SFPE to provide the user with a speed-density relationship that has wide acceptance and conservative estimations. However, there are other proposed fundamental diagrams. With the proper data points from a given diagram, a Pathfinder agent profile can be configured to model any speed-density curve.

Fundamental Diagram
Turnstiles

Turnstiles and Other Flow Constraints

The flexibility provided by Pathfinder can be used to simulate relatively complex flow situations. For example, by combining doors that have specified flow rates, way points, and wait times, Pathfinder can simulate queuing and proceeding through turnstiles.

Emergency responders can be directed to proceed up a stairway (against the evacuation flow) to a specified location and wait before proceeding to another location.

Doors and room speed modifiers can be scripted to activate or deactivate at prescribed times, simulating a changing environment during an evacuation.

Results Evaluation

Powerful Results Evaluation

Display of 3D results is available both during the calculation (to view current status) and immediately on completion. The 3D display allows the user to interactively display occupant movement, run back and forward in time, view paths, and select people to watch. A summary output file includes min, max, and average exit times and first-in and first-out times for rooms and doors. Detailed information is available in CSV files, including movement of individual people.

In addition to the 3D display, charts of room occupancy and door flow rates help you quickly evaluate points of congestion.

FDS Results Imports

With smoke and fire data imported from FDS results, Pathfinder can demonstrate areas of high danger by tracking occupant Fractional Effective Does (FED) of contaminants. This information is exported to a CSV file.

The smoke and fire is visually rendered in 3D simultaneously with the occupant evacuation. Additional visual analyses such as 2D/3D slices, particles, and boundary layers can be included. The 3D results viewer displays this in real-time.

FDS Results Imports