Representing the Spatial and Kinematic Constraints of Movement Assistance Devices within Evacuation Simulation Models

Michael Joyce

2024

Abstract

This research addresses a significant limitation in current evacuation simulation models by introducing an innovative method for representing movement assistance devices, such as evacuation chairs, hospital beds, wheelchairs, rescue sheets, and stretchers. These devices play a crucial role in evacuating people with reduced mobility (PRM). Existing models often oversimplify spatial constraints (size and shape) and kinematic constraints (movement speed and manoeuvrability) inherent to these devices, leading to inaccuracies in simulation outcomes. This research draws inspiration from other fields of study, primarily autonomous robotics, to review methods for their potential applicability in improving evacuation models. The research introduces a novel model called HEPTAD (Hospital Evacuation Planning Tool for Assistance Devices), designed to account for spatial and kinematic constraints of assistance devices while route-finding. The model involves the integration of a network within a 3D configuration space (C-Space), accounting for spatial and kinematic constraints. An advanced model, called ObjectController, is developed which extends HEPTAD to incorporate interactions between multiple devices and pedestrians using a novel combination of social forces and velocity obstacles, enabling realistic navigation. Object-Controller interfaces with established evacuation simulation model EXODUS to control both device and pedestrian movements. The developed model is tested through component and functional tests, demonstrating its capability to represent spatial and kinematic constraints, collision avoidance, and yielding behaviours. Techniques and software presented in this thesis could amount to more efficient evacuations involving PRM. This increases their safety as well as the safety of those evacuating around them, potentially preventing injuries and saving lives. This advancement holds particular significance in scenarios such as hospital evacuations, where accurate simulation of numerous device interactions is paramount for safety optimisation.