Research On Picking Path Planning For Multi-Mobile Robots In Intelligent Warehouse

In recent years,with the rapid development of e-commerce,logistics,as the core of its support,is facing enormous challenges.As one of the biggest demand points of e-commerce for logistics,warehousing logistics is undergoing tremendous changes.Traditional warehousing logistics has been difficult to meet the needs of the modern e-commerce industry due to inefficiency.After the successful application of Kiva system in Amazon warehousing logistics system,intelligent warehousing logistics system based on intelligent mobile robots has become one of the research hotspots in the current e-commerce and logistics industry.Under this background,this thesis studies the picking path planning problem of multi-mobile robots in intelligent warehouse.By solving the problems of task planning,global path planning and local dynamic path planning problems of multi-mobile robots,multi-mobile robots can move efficiently in intelligent warehouse without collision and complete picking task.Firstly,the intelligent warehouse system is analyzed and modeled.The characteristics,composition and operation process of the intelligent warehouse system are analyzed.The simplified schematic model of the intelligent warehouse system is established by using the grid method,and the characteristics of different picking modes are analyzed.Secondly,the task planning for multi-mobile robots in intelligent warehouse is studied.Before the mobile robot goes to the shelf to pick up goods,the order in the system is planned as a whole and the optimized task execution sequence is obtained.In this thesis,a task planning model for multiple mobile robots is established,and the genetic algorithm is used to solve the problem.Taking the picking task in the simplified schematic model of intelligent warehouse system as input,the task planning results are calculated and optimized,and the task planning process and results of multiple-mobile robots are simulated by simulation.Then,the global path planning and local dynamic path planning of multi-mobile robot picking are studied.For the intelligent warehouse environment,mobile time is selected as the path quality criterion.Based on the traditional A*algorithm,an improved algorithm is proposed to realize the global path planning of multi-mobile robot picking.Then,considering the local path conflict of multiple mobile robots,the priority method is used to determine the resolution strategy of each path conflict type,and a cooperative time-domain A*algorithm based on three-dimensional space-time graph and reservation table is proposed to solve the local path conflict problem of multiple robots picking.Finally,a simulation system of picking path planning for multi-mobile robots in intelligent warehouse is established in MATLAB.The validity of this method is verified by different comparative experiments.