Research On Vehicle Path Planning Of Urban Express

Recent years, with the rapid development of our country’s economy and the popularization of online shopping of the e-business mode, the urban express gradually gets into our daily life. In order to improve the competitiveness, each express company focus on reducing the express cost and improving the quality of service by reasonably planning express delivery path.This paper studies the urban express, analyzing its characteristics of complexity, economy, timeliness, service, uncertainty and multiple targets, and establishes two delivery models of urban express. The first one is the least couriers needed model with double time limitations in a region, where each transfer station gives high frequency, small volume and multi batches delivery services to its area. Each courier has double time restrictions:the longest one-trip delivery time and the longest working time of a day. The target is to calculate the least courier needed. The second one is the split delivery model with time windows and a mix walk of points and arcs in a road network, where express vehicles give delivery services both to the points of transfer stations and settled large customers and the arcs of scattered customers with big volume express. During the express there is time windows and the demand of customers can be divided. The target is the minimum total travel distance, the minimum punishment in violation of time windows and the least vehicles.On the solution of models, this paper uses graph transformation method to transform primal problem into VRP, and uses the improved aco to solve the examples of the paper by lingo and matlab, which verifies the feasibility of models and algorithm.