3D Shuttle Storage System Task Scheduling And Path Planning

The warehouse system is the material and information transfer center of the whole logistics enterprise distribution system,which determines the operating efficiency and cost of enterprise automation production to a certain extent.The 3D shuttle storage system is a highly intelligent and flexible compact storage system,which can realize 3D real-time scheduling and operation without elevator,it avoids the defects of traditional storage system,such as large equipment area,low running efficiency and poor flexibility,and has the potential to be widely used in practical production.AVS/RS(automatic access system)and SBS/RS(multi-layer Shuttle Vehicle System)mostly replace the whole storage system with single-layer and single roadway for simplified research,and lack of overall analysis of the storage system.This paper establishes a theoretical model of 3D shuttle storage system to study its task scheduling and path planning.The main research contents of this paper are as follows:(1)Based on the layout of the 3D shuttle storage system,according to the characteristics that 3D shuttle can realize three-dimensional motion without hoist,the two-dimensional plane path planning of single-lane operation or single-layer operation is extended to threedimensional space,and the straight movement between the two target cargo points in threedimensional space is transformed into the cross-lane movement that conforms to the 3D shuttle running in the horizontal operation roadway,and the longitudinal movement and cross-layer movement running in the longitudinal operation roadway.(2)Considering the maximum speed,acceleration,deceleration,reversing time and delivery time of 3D shuttle,the uniqueness of goods and the continuity of picking operation are taken as constraints to establish task scheduling path planning model.In order to reduce the number of crossing roadways and reversings so as to shorten the total time of outbound operation,the outbound strategy is studied,and the model solving ideas based on outbound strategy are combed.Based on genetic algorithm,an improved genetic algorithm based on outbound strategy is proposed.Ant colony algorithm,genetic algorithm and improved genetic algorithm with outbound strategy are designed to solve the model.(3)The effectiveness of ant colony algorithm,genetic algorithm and outbound strategy to improve genetic algorithm for task scheduling path planning model is verified.Through multiple sets of examples,the adaptability of the problem scale and the solution algorithm is studied,which provides reference for the efficient solution of task scheduling path planning model.The experimental results show that compared with ant colony algorithm and genetic algorithm,the improved genetic algorithm proposed in this paper reduces the number of crossing roadways by 40%,the number of reversing roadways by 36.7% and 40%,and the total outbound time by 25.3% and 24.9%,respectively.In the case of small,medium and large number of tasks,the improved genetic algorithm with outbound strategy has the highest solution accuracy,which can improve the efficiency of outbound operation and reduce the time cost of enterprises.