Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology
M. Kooijman Prototype of pedestrian simulation in Flexsim
Masters thesis, Report 2008.TEL.7239, Transport Engineering and Logistics.
Iv-Bouw & Industrie is a multidisciplinary engineering office that delivers constructive advice in the field of complex and/or moving contructions. Examples of prominent projects are the Beijing Great Wheel and the Amsterdam ArenA. Some projects involve large numbers of moving persons. A simulation provides insight in pedestrian flows and enables early discovery of bottlenecks. The Logistics Engineering division uses the simulation program Flexsim. However, this program was not yet suitable to be used for simulation of pedestrians. Objective of this master assignment is to develop a prototype of a pedestrian simulation in Flexsim.
A literature survey on existing methods to simulate pedestrians and the factors influencing the behaviour and speed of pedestrians has been made. Based on this survey it was decided to use a discrete walking space for the pedestrian simulation. The walking space is divided into cells of equal dimensions. A pedestrian occupies one cell at a time, which belongs to its current position. He can only move when one of the adjacent cells is not occupied by another pedestrian or obstacle. The pedestrian only checks the availability of a part of its surroundings. Which cells are checked depends on the characteristics of the behaviour of the pedestrian.
A case study where pedestrians try to reach the exit of a large indoor room is presented. Two strategies to reach the exit are modelled. In one strategy the pedestrian looks for the maximal walking space to minimize hindrance by other pedestrians. In the other strategy the pedestrian selects the cell that has the shortest distance to the exit. The user can change the proportion in which the two strategies are used. Locally, the pedestrians can take deviating decisions. When the pedestrian would cut an pedestrian by going to its desired cell, the pedestrian selects an alternative cell. When pedestrians cannot move, they become more impatient and try to claim space.
As a result of an emergency scenario the room with pedestrian must be evacuated. During the evacuation the pedestrians behave differently. They use a higher desired speed and care less about other pedestrians.
Experiments have been with the modeled pedestrians. With these experiments the values of several variables have been determined. The variables were adapted to fit the system time of the modeled pedestrians to the system time of pedestrians found in experiments described in literature.
Using a live experiment the modeled behaviour has been compared with the behaviour of real people. It became clear that the pedestrians in the simulation leave the room almost twice as fast as real persons. This is caused by the simulated pedestrians; when they move they move with the desired speed. But real people lower their speed when they see a congestion forming somewhere on their route.
The conclusion of this report is that different types of pedestrians can be modelled with Flexsim in different situations. The simulated persons initially left a room almost twice as fast as real people do. By lowering the desired speed to the same speed as in the live experiment, enlarging the waiting time and allowing just one people at a time to go through the exit, the real people still need 20% more time to leave the room. With the simulation model a restricted amount of people can be modeled real time. By making a movie, a larger amount of people can be showed real time with Flexsim.
Reports on Transport Engineering and Logistics (in Dutch)
