Research On Crowd Evacuation In Large Places Based On Social Force Model

With the rapid development of China’s economy since the reform and opening up,talents and migrant workers from all over the country are constantly pouring into this city,which has brought new impetus to the development of this city,but also brought huge risks to public facilities.When fire,earthquake and other emergencies occur,the visibility is often low due to smoke and lighting problems.This causes ordinary pedestrians who are not familiar with the venue structure to delay their escape time,cause crowding or stampede,and bring unpredictable casualties and economic losses.This paper mainly studies how to shorten the evacuation time and effectively reduce the adverse effects caused by disasters through reasonable evacuation guidance in public places.Its work mainly includes the following:Firstly,aiming at the problem that ordinary people are not familiar with the venue environment,this paper studies the behavior characteristics of the evacuation crowd in the low visibility environment,and develops the evacuation relationship strategy between the guide and ordinary people.Then,aiming at the low visibility environment,the basic social force model is improved,and the guided evacuation model of public places in the low visibility environment is established.Computer simulation technology is used to simulate and analyze the impact of the number of guide personnel,visibility range and the location selected by the guide personnel on the evacuation efficiency.Secondly,in view of the original neglect of people’s emotions and personalities in the process of crowd evacuation,the characteristics of the evacuated crowd are analyzed.Considering the important influence of panic on evacuees,the psychological behavior characteristics can also be simulated into the crowd evacuation model,and a social force evacuation model based on emotional infection is proposed,so as to better grasp the important influence of emotions in the evacuation process.The emotion is introduced into the original social force model,and the expected individual speed is modified.The group uses the received information and environment to choose the shortest path in time and space,so as to accurately analyze and describe the movement of individuals and people under different emotions,and establish a real crowd movement model.Thirdly,when evacuating with multiple exits,analyze the characteristics of the people to be evacuated,and conduct path planning while modeling the crowd movement.To solve the problem of poor local optimization ability and premature convergence of particle swarm optimization(PSO)algorithm in evacuation simulation,a crowd evacuation model based on improved PSO algorithm was proposed.In order to more realistically simulate the route selection of evacuated individuals in emergency situations,the original PSO algorithm needs to be properly adjusted.Therefore,factors that exist in the actual evacuation but are not taken into account by the particle swarm optimization algorithm,such as leaders,scope of vision,panic factors,etc.,are integrated into the algorithm to make exit selection,and the direction of evacuees is dynamically adjusted according to environmental factors and crowd movement.A more practical multi factor building evacuation model is established to avoid local congestion caused by premature convergence in the evacuation process,So as to provide a better simulation effect of evacuation in public places.