Research On Multi-AGV Cooperation And Optimal Control Based On UWB

Automatic guided vehicle(AGV)is a commonly used ground robot.With the continuous improvement of AGV application scenarios,Single AGV can hardly meet the common usage scenarios.Therefore the research needs of multi-AGVS system are very urgent.Multi-AGVS system mainly facing four problems.In the first instance,locate mode determines whether multi-AGVS system installation is convenient;in the next place,task allocation determines the mission of each AGV in the multi-AGVS system;additionally,path planning determines whether each AGV of the multi-AGVS system can reach the task point efficiently and conveniently;in the end,Conflict regulation determines whether the multi-AGVS system is stable and safe,only when the time and space conflicts between AGVS are avoided can the mission be completed efficiently and safely.First of all,aiming at the positioning problem of AGV,this paper adopted ultra-wideband(UWB)positioning method.Through the comparison of simulation experiments of various UWB positioning methods,a suitable UWB positioning algorithm is selected as the positioning method of AGV.Secondly,in view of the problems of many turns and proximity to adjacent obstacles in path planning,this paper improves the A* algorithm and proposes an improved A*algorithm for turning and staying away from adjacent obstacles.The proposed algorithm was verified by simulation and compared with other commonly used path planning algorithms.The simulation results show that the improved A* algorithm can reduce the number of turns and keep away from adjacent obstacles to a certain extent compared with the common path planning algorithm.It has some practical significance in AGV system using UWB position.Aiming at multi-AGVS task assignment problem,this paper adopts genetic algorithm as task assignment algorithm.The shortest total path of AGV was taken as the objective function of the genetic algorithm,and AGV was assigned according to the priority of tasks.In view of the multi-AGVs collaboration and optimization control,the road busyness factor was firstly introduced in this paper,and a tiled busyness factor strategy was proposed,which could reduce reduce conflicts along the same path and the collisions caused by AGV deviating from the road.Simulation results show that the proposed algorithm can effectively reduce the repeated paths between AGVs.Secondly,velocity correction,geometric correction and time window are used to adjust the different conflicts in the multi-AGVS system.The above algorithm is simulated and verified,and the experiment shows that the algorithm can effectively adjust the conflict problem in multi-AGVS system.Finally,a three-dimensional time window is proposed in this paper to realize the direct observation of the location and time node of the time-space conflict of AGV in the road.Simulation experiments show that the three-dimensional time window can directly observe the path of AGV in the map.Finally,this paper designs a set of upper and lower computer control system to send the starting point,destination and map information to the AGV,and the AGV will plan the path,avoid obstacles and walk on its own according to the information.At the same time,the position information of AGV is displayed in the upper computer in real time.