Path finding and collision avoidance in crowd simulation

Abstract

Motion planning for multiple entities or a crowd is a challenging problem in today's virtual environments. We describe in this paper a system designed to simulate pedestrian behaviour in crowds in real time, concentrating particularly on collision avoidance. On-line planning is also referred to as the navigation problem. Additional difficulties in approaching navigation problem are that some environments are dynamic. In our model we adopted a popular methodology in computer games, namely A* algorithm to find the first itinerary of each entity. The idea behind A* is to look for the shortest possible routes to the destination, not through exploring exhaustively all possible combinations, but utilizing all possible directions at any given point. In order to deal with collision avoidance problems, priority rules are given to some entities as well as some social behaviour. These rules solved the problem of disorder in the crowd movement.