Study On The Vehicle Routing Problem Based On Vehicle Coordination

The vehicle routing problem(VRP) is an optimization problem to design delivery or collection vehicle routes of minimum total cost starting and ending at the depot. The VRP plays an important role in logistics distribution. Since the optimization of the VRP is very important to decrease logistics cost and improve serve level, it has been attracting more and more interest from logistics operators and operation researchers. To date, most studies on VRP are based on vehicle uncoordinated strategy, in which each vehicle serves their customers independently, and there is no coordination between any two vehicles. If the information of traffic or demands of customers are uncertain, this strategy will result in much wastage of resource of vehicle capacity. Serving under the vehicle coordinated strategy, vehicle capacity will be used more fully and total serve time will be more less, such that the cost is decreased while the serve quality is kept or even improved. With continuing advances in information and communication technology, vehicle real-time coordination is becoming one of main tendencies of the VRP research. In this paper, under the condition that the information of customer demands and traffic are uncertain, the VRP based on simple coordinated rules are discussed. Vehicle coordinated routing strategies are designed. The effectiveness of these strategies is testified efficiently based on theory analysis and computing results. The main content of this paper is shown as follows.Vehicle coordinated strategies are provided, which include two vehicle-paired strategy, three vehicle-paired strategy, and four vehicle-paired strategy. The expected routing lengths, the expected loading times and system serve time are discussed. Emulation tests are applied to produce computation results to inspect effectiveness of these strategies.Improved sweep routing strategy for large-scale stochastic vehicle routing problem is discussed. A vehicle-load model is constructed and a heuristic algorithm for the model is designed. The effectiveness of the strategy is tested by imitationVehicle coordinated strategy in large scale logistics is discussed. The strategy consists of two stagy. In the first, all customers are clustered into several sub-zones according to a sweep algorithm, then vehicles in each zone are coordinated to serve.