Path Planning And Collaborative Scheduling Algorithm For Forklift AGV

With the rapid development of industrial intelligence,forklift type AGV(Automatic Guided Vehicle)has been widely used in intelligent storage and other scenarios.Good path planning algorithm and reasonable cooperative scheduling strategy can significantly reduce the transportation time of forklift AGVs,which is an important guarantee to improve the operation efficiency of intelligent storage.Although important progress has been made in path planning and cooperative scheduling of AGVs,when it comes to forklift-type AGVs,due to their vehicle structure and operating environment,path planning and cooperative scheduling need to consider end-point positional constraints,slow turning and reversing speed,etc.in order to achieve better results.There are not many related researches,and the existing path planning and cooperative scheduling algorithms for forklift-type AGVs have problems such as long path running time and strong scenario limitations.Therefore,this thesis investigates the path planning and cooperative scheduling algorithms for forklift AGVs.The main research contents are as follows:(1)In order to improve the operational efficiency of forklift-type AGVs,a forklifttype AGV path planning algorithm based on the improved A* algorithm is proposed.By increasing the turning cost in the cost generation value of A* algorithm,the number of turning points of the planned path is effectively reduced,thus reducing the time cost of forklift AGVs due to turning and improving their operation efficiency.On this basis,considering the characteristics of forklift AGVs with end-point positional constraints,the A* algorithm is further improved by adding dynamic weights to enable it to dynamically regulate the cost surrogate value of the A* algorithm according to the positional state of forklift AGVs,so as to plan a path that satisfies the kinematic constraints of forklift AGVs.Simulation experiments verify the effectiveness of the algorithm,and under the same experimental conditions,its average path running time is reduced by about 10%compared with that of the backtracking-based forklift AGV path planning algorithm,and a feasible path can still be designed when the backtracking path planning fails.(2)In order to realize the safe and collision-free cooperative operation of multiple forklift AGV systems,the cooperative scheduling algorithm of multiple forklift AGVs based on the application-response method is proposed.In this paper,a cooperative interaction mechanism of multi-forklift AGV based on application-response method is designed.On this basis,a time-window-based multi-forklift AGV conflict detection and coordination algorithm is proposed to realize conflict detection and classification in multi-forklift AGV systems,and conflict coordination strategies such as speed reduction and waiting,path re-planning and time-window right-shifting are designed according to the conflict types,and then multi-forklift AGV cooperative scheduling is realized.Simulation experiments have verified the effectiveness of the algorithm,and the system running time is reduced by 6% on average compared with the master node-based cooperative scheduling algorithm for multi-forklift AGVs.