Particle Swarm Optimization Applied In Crowds Evacuation Simulation Of Single Floor Building

These years more and more accidents took place at home and abroad. It is very important to evacuate crowding people in a short time. How to estimate the evacuation efficiency, or how to judge whether a building design accords to the safe standard? The most direct approach is to arrange evacuation drills. However, there are some disadvantages associated with these drills. Firstly, these drills are usually dangerous, especially when a large number of participants are involved in the drills. Secondly, these drills usually require relatively much time and a lot of money to prepare and operate. Furthermore, the cost increases dramatically when the number of participants increases or when the drill fails and a new one needs to be redesigned. Lastly but not least, it is typically the case that only limited number of trials can be performed in each evacuation drill due to the time-consuming planning and enormous cost. Actually, a practical approach is to simulate the crowd evacuation in computer.At present most crowds evacuation simulation techniques at home and abroad are based on Agents, they are called micro-simulation. These techniques focus on the decision process and behavior of the agents, but neglect the interaction of the agents. Because people usually feel scared and exert animal's attributes at danger and urgent situations, plus considering the background and idea of Particle Swarm Optimization, this article apply the idea of PSO to the crowds evacuation simulation, to control pedestrians'movement and make the path choice of pedestrians. The original PSO allows particles to fly in the solution space absolutely freely, but the pedestrians in the reality should avoid the conflict with obstacles and other pedestrians. Furthermore, it is not the fact that the pedestrians don't change the path until they run into the obstacle, actually they change the path when they have a distance with obstacles. Therefore, people don't walk strangely and swing left and right, the path should reasonable and appropriate. To resolve the aforementioned incompatibility issues between original PSO and people's finding path in reality, we should modify the original PSO to be compliant to the crowds evacuation simulation.This paper, firstly, analyzes some popular stimulation technology at home and abroad at present, summaries the characteristics of each model, the suitable scene and the advantages as well as the disadvantages and establishes appropriate simulation model according to the actual situation. And then, PSO algorithm is applied to individual routing. Finally, a simulation prototype system EvacuaSim is developed, which applied to the simulation and model in two real scene. This simulation system can meet the requirements of the crowd evacuation simulation, displaying the process directly, and offering necessary data for analyzing and guidance for the practical plan.