The Research On Robot Polishing Attitude Modification And Contact Force Control Technology Based On Six-Dimensional Sensor

In order to improve the precision and surface consistency,robots are gradually replacing humans in the field of large workpiece grinding.Due to the inevitable errors in the manufacturing,clamping and calibration of large-size workpiece,the offline programming path based on geometry cannot achieve good surface fitting,resulting in unsatisfactory grinding and polishing effect.However,the robot research based on force perception is an important means to improve the adaptability and intelligence of the robot system.Therefore,this paper studies and discusses posture correction and contact force control with the help of the force sensor at the end of the mechanical arm under constrained conditions.Researches on pose-based torque impedance control and position-based force impedance control are carried out to improve the robot's profiling and fitting ability and improve the robot's force control performance in unknown environments.This article mainly carried out the following innovative work:First,by analyzing the contact state and contact force of the robot during the grinding and polishing process,the research on the torque impedance control based on the pose is carried out,and the Matlab/Simulink simulation model is established.By analyzing the torque response characteristics under different impedance parameters,the parameter selection principle is derived.Aiming at the flutter problem in the posture correction,an improved zero-torque control strategy is proposed to improve the robot's profiling ability and dynamic adaptability.Secondly,in view of the insufficient adaptability of traditional impedance control to the unknown environment,the impedance control model is analyzed for error,and an impedance control algorithm based on model reference adaptive is proposed to estimate the stiffness and position of the environment online,reduce the impact of robot collision,and improve the unknown Environmental adaptability,the effectiveness of the algorithm is verified by Matlab/Simulink simulation.Finally,the simulation fitting experiment and contact force control experiment were carried out on ABB grinding experiment platform to verify the effectiveness of the above control strategy.The grinding quality under the control mode of position(without force control),impedance force control mode and force/posture hybrid impedance control mode are compared and analyzed,and the application effect of the force/ posture hybrid impedance control strategy proposed in this paper is verified.