Singular Avoidance And Vibration Suppression In Trajectory Planning Of 6-dof Serial Robot

The industrial robot, representative products of automatic equipment, applied widely in the factories. In the face of the increasingly wide application occasions and the more strict requirements, improving the motion accuracy of the industrial robot has become a hot research in recent years, especially in the continuous trajectory control field. In this paper, we design the trajectory algorithm to achieve the reasonable configuration of the parameters such as position, velocity and acceleration, so as to improve the accuracy of motion.First, in order to solve motion discontinuity, tracking performance variation caused by the motion accuracy of the problem in singular zoom.a singularity avoidance method is given. This method does not need decomposition of Jacobian matrix, only need add the damping in singular direction. only at the expense of part of the motion accuracy in the singular direction, this method ensures the continuity and stability of the running speed of the robot.Next,the robot flexibility is the main factor that affects the robot’s running precision in non singular region. to solve it, the dynamic equation of joint flexibility is established. the differential vibration equation of robot is obtained through it. According to the solution of differential vibration equation, a performance evaluation index called single joint volatility is presented. The accuracy of the simplified differential equations is verified by ADAMS simulation, and the validity of the single joint volatility is analyzed. It is proved that controlling single joint volatility can restrain the high frequency vibration and improve the running precision of the robot.Then, a time optimization model containing speed, torque and jerk constraints is established by parameter method for improving the motion speed of the robot.an optimization algorithm is presented, which is firstly searched for the control points, then the control points are interpolated in the plane of the three spline curves, and the optimization of the trajectory is realized. The effectiveness of the proposed algorithm is demonstrated by simulation analysis.Last, in the Kawasaki robot, the jerk effect on the vibration of a flexible robot is verified, which illustrating necessity of controlling the jerk. Through different forms of interpolation,the correctness of the ADAMS simulation model and the simplified vibration differential equation is verified, which represent this model can describe the actual situation and effectiveness of the basis of conclusion.