Research on Improved Hybrid Particle Swarm Optimization for Vehicle Routing Problem with Time Windows

Vehicle routing problem with time window (VRPTW) is a very important combinatorial optimization and nonlinear programming problem and it has important practical value in the field of transportation, distribution and logistics. Traditional intelligent optimization algorithms have the common defects of early convergence and easily falling into local optimal solution in solving VRPTW. An improved hybrid particle swarm optimization (IHPSO) has been presented in this paper for the solution to the VRPTW. Population entropy is introduced to ensure the diversities of the solution. Some post-optimization procedures, such 2-opt, 1-1 opt and 1-0 opt, are adopted to optimize the inner or router route and modify illegal solutions. The advantage of the proposed algorithm is proved by the simulation based on Matlab language. The results shows that IHPSO can be dramatically increase the probability of the finding the optimal solution as well as shorted the searching time. It is a feasible and effective algorithm for VRPTW.