Research On Structure Design And Path Tracking Control Of Forklift AGV

With the acceleration of intelligence and automation in the warehousing and logistics industries,ordinary forklifts can no longer meet the needs of practical applications,and unmanned forklift AGVs have emerged.This paper takes the unmanned forklift AGV as the research object,and mainly conducts research on two aspects: structure design and path tracking control.The main work of the thesis is as follows:(1)Designed the overall mechanical structure of the forklift AGV,including the drive system,forward movement system,fork system and body.The finite element simulation method is used to carry out strength simulation and modal analysis of the key components of the forklift AGV.The results show that the structure and materials of the forklift AGV can meet the requirements of working conditions.Subsequently,the ADAMS software was used to test and analyze the lateral stability of the whole vehicle.Through four sets of comparative tests,it was verified that the forklift AGV can work normally under the three working conditions of no-load,full-load,full-load and lifting goods without overturning,which reflects the good stability.(2)From the perspectives of kinematics and dynamics,the forklift AGV is analyzed,as a result of which a vehicle motion model is established based on kinematics and dynamics.Among them,the kinematics model is a state space model obtained after discrete linearization according to the steering characteristics of the forklift AGV;the dynamic model is a linearized model constructed based on the yaw motion.When the input is consistent,the comparison of the output results of the two models with the ADAMS model is able to verify the accuracy of the constructed dynamic model,which lays the foundation for the follow-up forklift AGV path tracking control.(3)Designed the control system scheme of the forklift AGV,including the hardware system and the software system.The hardware part mainly includes the overall structure of the hardware control system,the main controller and the control system circuit;the control software is developed based on Lab VIEW,which realizes functions such as initialization,data management,position calculation,path planning,task management,and power management.(4)Aiming at the path tracking problem of forklift AGV,a fuzzy PID method based on genetic algorithm optimization is proposed.The genetic algorithm is used to optimize the control rules of the model PID,which further reduces the error of fuzzy PID path tracking.And feasibility and accuracy of the algorithm is verified by experiments.Finally,a path tracking control experiment was carried out in a sugar factory.First,the internal grid map of the factory was established,and then the planned path was obtained.Based on this path,a fuzzy PID control algorithm based on genetic algorithm optimization was used to perform path tracking control for the forklift AGV.The experimental results show that the tracking process error and the target position error can meet the requirements,which verifies the feasibility and effectiveness of the path tracking algorithm in this paper.