Visual Positioning Compensation Of Mecanum Wheeled AGV Based On Motion Error Analysis

It is necessary to realize the transfer of fixtures between the threedimensional warehouse and the machine turntable through AGV when the co-line production line undergoes automatic product changeover.In addition,we need to increase the positioning accuracy of the AGV to 3mm to achieve the zero-point positioning of the fixture sub-disk and the master disk.However,existing products usually carry a small displacement mechanism on the AGV to achieve the accuracy,but this method not only increases the weight of the AGV,but also increases its cost.Therefore,how to achieve the positioning accuracy of the AGV without being equipped with an auxiliary positioning mechanism is an urgent problem to be solved.In response to the above problems,this article has carried out a series of error analysis on the kinematics model of Mecanum wheeled AGV.In addition,this article also carries out related experiments to modify the kinematics model,which effectively improves its motion accuracy.Furthermore,this paper designs a visual positioning compensation algorithm,develops a positioning compensation system and carries out experiments to verify its effectiveness.The experimental result shows that the designed visual positioning compensation system can improve the final positioning accuracy of the AGV to(±3mm,±2mm,±0.1°).The main research content of this article is divided into three parts:(1)Kinematics model error analysisA kinematic model of Mecanum wheeled AGV is established,and the motion error of AGV is analyzed based on the kinematic model,including roller offset angle,wheelbase,motor speed and roller deformation.On the basis of error analysis,a method of correcting roller offset angle and wheelbase is proposed to improve the AGV movement accuracy.Meanwhile,the error analysis also provides theoretical guidance for the subsequent positioning compensation strategy.(2)Establish a visual positioning compensation systemA DM code pose calculation algorithm is proposed to obtain the deviation between the current pose of the AGV and the target pose.In this paper,a visual positioning compensation algorithm is designed,which feeds back the AGV pose deviation to the PLC controller and drives the car to move to achieve positioning compensation.(3)Engineering application of positioning compensation system based on motion error analysisAccording to the correction method proposed by the motion error analysis,relevant experiments are carried out on the AGV to correct its kinematics model and improve its motion accuracy.A visual positioning compensation system is built to improve the final positioning accuracy of the AGV,and it is applied to an automotive powertrain automated production line of Shanghai Smart State Technology Co.,Ltd.In summary,this article deeply analyzes the motion error of the Mecanum wheeled AGV,and effectively corrects the kinematics model.And this article successfully applies the self-designed visual positioning compensation algorithm to the AGV of SSS,which effectively improves its final positioning accuracy.This method not only provides new methods and technical guidance for the flexible conversion of automotive powertrain automated production lines,but also has reference significance for highprecision assembly fields such as aircraft manufacturing and maintenance,and aerospace vehicle transportation and assembly.