Research On Optimization Of Transshipment Operation Scheduling In Railway Container Central Station Based On AGV Mode

Due to the reform of railway goods transportation and the benefit from the "the Belt and Road" policy,rail freight market share is gradually increasing and developing rapidly in recent years,and because of its low energy consumption and the characteristics of high efficiency railway container transportation has developed into one of the optimal transportation choices in countries trade.This paper draws on the AGV dispatching mode of the new mode railway container terminal of the Lehrte giant distribution center in Hanover,Germany,and studies the transshipment operation method of the new type railway container center station based on the AGV mode,so that the containers can be transferred quickly between freight trains,thus speeding up the transshipment efficiency of railway containers.Specifically,this study is based on AGV model of railway container terminal transit assignment of gantry crane and shuttle scheduling problem.To reduce the long walking distance for dispatching container and cross interference of gantry crane,a new generation of yard adopts automatic sorting system(containing several shuttles).The automatic sorting system replaces the gantry crane to solve the long-distance horizontal movement of container transportation,and the gantry crane is only responsible for the continuous transfer between the train and the automatic sorting system,as to avoid the excessive movement of the crane in the yard.This paper mainly studies the following parts:(1)First,the development of railway container transport,the present situation,the trend,and the significance of developing new mode of railway container terminal are described in the paper,and the main technical performance of traditional container station and a new AGV-based container station transport field are contrasted.Compositions,operation processes,the advantages and disadvantages and technical performances of different modes of automatic sorting system are expounded in this paper.(2)Second.graphical abstraction is done according to the characteristics and composition of the automatic sorting system.An optimization model with the objective of minimizing the maximum completion time of container loading and unloading tasks and the basic constraints of unique container path,time conflict of container operation sequence,shuttle and exchange area is established.The structure of the container path is illustrated with the space-time network diagram.Combining the rule of path feasibility judgment with the microevolution mechanism,a microevolution algorithm suitable for model and automatic sorting system is designed to solve the problem.(3)Last,according to the German Hannover Lehrte’s giant hub as the prototype the example is designed and optimized.The effectiveness of the proposed algorithm is verified through comparing the results of CPLEX and microevolution algorithm.By comparing the results of large-scale examples under three and four exchange area modes,it is concluded that the objective function under four exchange area modes is better and the workload of the shuttle is more balanced,which is related to the selection of container path,the number and position of exchange area and the distribution of original data.In addition,by comparing the microevolutionary algorithm and genetic algorithm,it proves that the microevolutionary algorithm designed in this paper is efficient in solving problems.