Research On High Speed And High Precision Motion Optimization And Dynamic Control Method For Robot

Robot has been widely used in modern industry.With the development of robot and automation technology,the accuracy and stability of high-speed motion are becoming an important index of robot performance,and it is a factor that should be considered in the motion control system of a robot.In the case of high speed motion,the nonlinear control characteristics of the robot are very significant,and the actual complexity of the complex factors also seriously affect the control accuracy of the robot,it is of great theoretical significance and practical value to research on motion optimization and dynamic control method of industrial robot to meet the high-speed high-precision control objectives.In the light of the practical characteristics of motion control of industrial robot,the basic theory of high-speed and high-precision control is researched in both kinematics and dynamics.At first,research the forward velocity control method of continuous motion path and the Cartesian space interpolation method of straight line and Arc motion path.And then,introduce S-type flexible acceleration/deceleration planning method and multiple spline curve velocity planning method to reduce the impact and vibration of robot when it starts and stops.As for the NURBS curve(non-uniform rational B-spline),a forward-speed segmentation method based on the geometric properties of the curve is studied.Finally,a kinematic parameter identification method based on Newton-Euler iterative equation is studied,and a feedforward torque control model based on dynamic model is established.The main contents of the study are as follows:(1)The forward velocity control method of continuous path is researched,and the transition curve is added to each adjacent path,and the velocity of the start and end points of each path is planned.And the Cartesian space real-time interpolation method of motion path such as straight line,Arc and transition spline curve is also researched.The simulation results show that the method avoids the frequent start and stop of the robot at the transition of the path and improves the velocity of the robot.(2)For the straight and circular path,the S-type flexible acceleration/deceleration planning method is researched to reduce the rigidity impact of the robot when it starts and stops,and in order to cope with the high-load and high-speed movement of the robot,multiple spline curve velocity planning method is proposed.In order to obtain the effect of acceleration and deceleration without impact and flexibility,the trigonometric function velocity planning method is researched.For NURBS curves,the curves are generated using global interpolation and first-order Taylor expansion.And then,the forward-speed segmentation method based on geometric characteristics such as centripetal acceleration and chord error is established.The experimental results show that the above-mentioned velocity planning method can reduce the impact of start and stop period of the robot and improve the position control precision of the industrial robot to a certain extent.(3)The dynamic parameters of the robot based on the Newton-Euler iterative equation are researched and the kinetic equation of the basic dynamic parameters is obtained by numerical solution.Then solve the nonlinear optimization problem to obtain the optimal Fourier excitation trajectory,use the weighted least squares method to solve the stationary equation to obtain the basic dynamics parameters of the robot.The feedforward torque compensation method based on the robot dynamics model is established,according to the theoretical trajectory of the robot,the dynamic buffer queue is established,and the angular velocity and angular acceleration of each joint are calculated according to the central difference method.In the servo motor position control mode,the feedforward compensation torque of each joint of the robot is calculated real time in each interpolation cycle and sent to the current loop at the bottom of the motor to compensate for the feedback torque of the motor.The experimental results show that the feedforward torque control based on the dynamic model can improve the response speed of the robot to a large extent,and reduce the tracking error of the joints of the robot and the jitter of each joint when the robot is stopped.(4)Built a robot control system based on the x86 platform and embedded real-time operating system and in this platform,the high-speed and high-precision motion control algorithm is experimentally verified.The experimental results prove the feasibility and effectiveness of the above algorithms and theories.