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

Key Features

• Take advantage of modern agent-based simulation techniques performed in a precise, continuous 3D environment.
• Quickly create simulation models with Pathfinder’s built-in drawing features.
• Automatically import geometry from a 2D and 3D DXF files, FDS, and PyroSim.
• Use multiple simulator modes, including a new steering mode and a mode based on calculations from the SFPE Handbook.
• New “locally quickest” path selection system for more intelligent path planning.
• Elevators in addition to stairs and ramps, can be used for evacuation.
• Updated graphical interface and reduced load time in the 3D results view.
• Improved processing of imported geometry.
• Optimized performance of the simulation engine, including parallelization for multi-core CPUs.
• Enhanced realism in the movement behaviors of the individual occupants.
• New behavior scripting for adding additional movement goals prior to exit.
• New 3D occupant models to choose from, including a fire fighter model.
• Fine tune occupant characteristics and customize the appearance of occupant groups.
• Impress clients with Pathfinder’s high-quality 3D results.
• View detailed charts of room occupancy and door usage.

Model Creation

Since much of the time spent creating evacuation models is often devoted to describing the relevant geometry, Pathfinder includes several powerful features that are specifically designed to save time and avoid duplicate work. Existing DXF, FDS, or PyroSim files can be quickly converted into evacuation models using Pathfinder’s innovative floor extraction tool. Evacuation models that exactly match imported geometry can be created with just one click. Alternately, built-in drawing tools are available to create simulation geometry from scratch or with the aid of floor plan images.

Working with doors and stairs is also a streamlined process in Pathfinder. Graphical tools make it possible to quickly add or modify doors and stairways while carefully controlling the exact location and extent of each element.

Several options are available to add occupants to a simulation model. Using graphical tools, occupants can be added either individually or using a bounding box. Alternately, an approach based on room selection is available that can be used to add occupants to a single room or the entire model.

Individual occupants can be assigned specific properties or you can manage these properties using a powerful profile system. Each occupant belongs to a profile that controls speed, initial delay, size, and appearance. Profiles allow each of these characteristics to be constant or generated at simulation time based on uniform or normal distributions. Occupants can also be assigned to use specific exits to help simulate varying levels of familiarity with a building.

Movement Model

Pathfinder uses agent-based artificial intelligence. Each occupant has individual traits, goals, and perceptions. This allows groups of occupants to organize themselves into natural flow patterns. As a result, occupant motion looks smooth and realistic.

Rather than modeling occupants on a grid or as particles in a flow field, Pathfinder moves occupants in continuous 3D space. At each time step, every agent examines the surrounding environment and takes action based on their own conditions and goals.

In his 1987 paper, Flocks, Herds, and Schools: A distributed Behavioral Model, Craig Reynolds introduced the concept of steering behaviors. He showed that by combining three behaviors (collision avoidance, velocity matching, and flock centering) it was possible to efficiently simulate the movement of a flock of birds in real time – a feat that was otherwise computationally unmanageable.

The movement technique used in Pathfinder, inverse steering, is a variant on this original steering technique that allows agents to evaluate the cost of moving in a particular direction. At each time step, agents move in the direction that minimizes the overall cost.

Pathfinder also includes an alternate movement model based on equations from the SFPE Engineering Guide on Human Behavior in Fire. Occupant motion follows the velocity profiles given by SFPE, while flow through doors is controlled by the SPFE flow assumptions. In this mode, Pathfinder reproduces a first-order hand calculation using the SFPE assumptions. This allows you to quickly evaluate a model using these widely-known movement assumptions, even for large, complex buildings.

Pathfinder is subject to an ongoing validation process based on current and emerging movement research. To verify that individual elements of the simulator are functioning properly, simulation results are routinely compared with hand calculations. To validate the overall behavior of the simulator, real evacuation scenarios are recreated in Pathfinder and the results are compared with data gathered by independent researchers. In addition, comparisons with other evacuation simulators illustrate how Pathfinder performs relative to other modeling approaches.

Visualization

Pathfinder will impress clients with high-quality human models, movement trails, floor layouts, and other powerful 3D visualization techniques. Dynamic level-of-detail and view culling make it possible to view the motion of thousands of occupants in real time. Pathfinder records high-resolution screen images and movies, allowing you to view results on any computer.

Pathfinder output also includes quantitative time history data for door flow rates, and room-based occupant counts. 2D plots of time history output can be immediately viewed within Pathfinder.

Pathfinder Licensing and Pricing

For more information, please visit our licensing information page, or order online.

Educational Licensing

Free licenses are available for classroom use. For more information, contact sales@thunderheadeng.com.

This material is based upon work supported by the National Science Foundation under Award Number DMI-0521897. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.