Study of the vehicle routing problem with time windows based on improved particle swarm optimization algorithm

To overcome that the standard particle swarm optimization algorithms can not find good solutions of solving the vehicle routing problem with tim windows, an improved particle swarm optimization algorithm for vehicle routing problem with time windows (VRPTW)was proposed. In the improved algorithm, different particles are assigned specific tasks. Better particles are given smaller inertial weights, while worse ones are given larger inertial weights. And the particle´s inertial weight are adaptively adjusted according to its fitness function. These strategies improve the PSO algorithm at the aspects of diversity and the balance of exploration and exploitation. In comparison with other algorithms,the Improved Particle Swarm Optimization is proved an efficient method for VRPTW.