Research On Active Compliant Control Of Grinding And Polishing

With the development of intelligent manufacturing,the increasing robots are applicate in grinding and polishing.In the process of robot grinding and polishing,how to control the grinding and throwing force has important significance to the quality of grinding and polishing.Therefore,in this paper,the robot end force control algorithm is researched in robot grinding and polishing process.(1)In order to control the end contact force of robots,a force-mixing control algorithm is proposed to deal with the stress of the robot end.The workpiece coordinate system is used as the robot base coordinate system,and the robot end force control is realized by the force position hybrid control algorithm based on the joint position control.(2)Based on the external force disturbance and surface grinding and rubbing in the process of grinding and polishing robots,this paper proposes variable parameter PID control method and the force-position hybrid control algorithm based on vector method.According to model of PID controller parameter change,the PID controller with the control parameters changing with the working condition is established to improve the ability of the robot to control the single force in the grinding and polishing process.By analyzing the surface model and the principle of surface tracking control,a force based hybrid control algorithm based on vector method is proposed to realize the multi-dimensional force control and surface tracking of the robot.(3)The simulation experiments are carried out in MATLAB and Adams simulation environment.By verifying the variable parameter PID control algorithm in MATLAB,it shows that the end force is stabilized within 0.8s when the external force is disturbed,and the multi-dimensional force is stabilized within 1s after verifying the vector control algorithm.In the MATLAB and Adams joint simulation experiments,the end force is stable within 0.8s and has the effect of surface tracking,and the two control algorithms are verified.(4)The experimental results show that the variable PID is 70% higher than the conventional PID stabilization rate,and the robot can maintain the steady state when the multi-dimensional force is disturbed by external force.Analysis of experimental curve changes,proved that the proposed control algorithm to achieve the desired control effect.