| The rapid development of modern industry makes robots more and more used in various industrial operations,and at the same time puts forward higher requirements on the control performance of robots.Because the robot system is a system with strong coupling and many uncertain factors,there are many problems in the robot control,and the error problem in the robot trajectory tracking control process is one of the most important problems.This topic studies the significance and role of gravity compensation in improving robot trajectory tracking accuracy during robot motion control.This subject takes six-degree-of-freedom robot as the research object,establishes the kinematics and dynamics model of the robot system,gives the analytical solution of the robot's forward and inverse kinematics,and generates the running trajectory by means of polynomial interpolation,which verifies the rationality of the model.The workspace of the robot was established by Monte Carlo method,the changes of gravity,inertial force and Coriolis force in the robot dynamic model and the influence of gravity moment on the pose of the robot were analyzed,and the gravity compensation of the robot was proved.Necessity.In this paper,based on the establishment of robot dynamics and kinematics models,a gravity feedforward compensation PD control method based on the robot model is designed.This method introduces gravity compensation terms on the basis of the PD controller,which can effectively solve the problem.The tracking error caused by the gravity of the joint link.The simulation results show that the gravity feedforward compensation PD control method based on the robot model can effectively improve the accuracy of the system trajectory tracking under the premise of the accurate compensation model,and has good response characteristics and tracking capabilities.Aiming at the problem that the compensation model does not match the actual model of the system,the control effect becomes worse,and the system has trajectory tracking errors.Chapter 5 analyzes the limitations of the gravity feedforward PD controller when the compensation model is not completely matched.An adaptive iterative controller is added to the feed-forward PD controller to solve the problem of trajectory tracking error when the compensation model is incomplete.Simulation results show that the designed adaptive iterative controller can effectively solve the problems of non-linearity,uncertainty and disturbance in robot control.Compared with the PD control method based on robot model-based gravity feedforward compensation,the tracking and response capabilities of the system are obtained.Significantly increased.In summary,in order to solve the trajectory tracking error caused by the gravity moment in the robot system and improve the performance of the trajectory tracking of the system,this paper studies several different controllers.By comparing and analyzing the control effects of different controllers,the system is improved accordingly.The designed adaptive iterative learning controller with gravity compensation can effectively compensate the gravity moment of the system,improve the control accuracy,and still have a good control effect when the system model is not completely established. |
PDF Full Text Request