Research On AGV Route And Scheduling Optimization In Automated Container Terminal

In recent years,intelligent and information construction has become an important means to enhance the core competitiveness of the port,which is also the key to reduce logistics costs and improve logistics efficiency.Automated container terminal has become the main trend of the future development of container terminal due to its efficient,unmanned and automated operation.AGV,also known as automated guided vehicle,which realizes the independent planning and adjustment of the driving path,load and unload cargoes through utilizing the navigation device to know information of the surrounding environment,has been widely used in the automated container terminal.However,with the continuous increase of port throughput,the operation and transportation pressure of the automatic terminal is increasing.As a result,the path conflict and road deadlock of AGV are increasingly prominent in the limited container horizontal transportation road.In order to effectively solve the problem of AGV path conflict and road deadlock in automated container terminals and improve the horizontal transportation efficiency of containers,this paper studies the optimization of AGV routing and scheduling in automated container terminals.The main research contents are as follows:(1)The automated container terminal is classified according to the yard layout.On the basis,this paper analyses the characteristics of AGV driving path in different categories of automated container terminal,the current situation and development trend of AGV path planning and scheduling.(2)The pheromone feedback mechanism,pheromone update rule and state transition rule of traditional ant colony algorithm were improved and integrated into multi-agent system.AGV is regarded as ant-agent,carrying pheromones with negative feedback mechanism enter transportation network.The concept of congestion is introduced,and a new state transition rule is established on the basis of congestion threshold.A solution mechanism for path conflict is constructed.On the basis,an AGV control algorithm based on Ant-agent(Ant-agent algorithm)is proposed.(3)Based on the platform of multi-agent simulation software netlogo 6.1.0,the AGV control algorithm performance test system is developed on the basis of designing the test start stop module,test parameter setting module,test environment module and test result module.The performance of Ant-agent algorithm is verified by two-stage uniform design experiment,and the optimal parameter combination of ant-agent algorithm in AGV path optimization is determined.The simulation result indicates that compared with traditional methods,Ant-agent algorithm has significantly improved the performance of collision avoidance,unlocking and transportation efficiency.(4)Based on the AGV control algorithm performance test system,the application of Ant-agent algorithm in AGV scheduling is simulated through two-stage uniform design experiment.As a result,the optimal scheduling strategy of AGV is determined,and the scheduling performance of Ant-agent algorithm is analyzed on the basis of simulation output.The result indicates that when the transportation task is heavy and system is under large load,Ant-agent algorithm has better scheduling performance.The Ant-agent algorithm proposed innovatively in this paper can update the congestion degree of each node in real time according to the location of AGV in the transportation network,controlling the driving state of AGV,improving the collision avoidance performance of transportation system as well as empowering it to unlock road.As a result,it effectively solves the path conflict and road deadlock problem and improves the transportation efficiency of AGV.To sum up,the optimization of AGV route and scheduling in automated container termianal are achieved simultaneously through researching the control of AGV.