Abstract: In order to solve the problems of the robot positioning accuracy reduction and system instability caused by the elastic deformation of the follower arm with low stiffness when the Delta parallel robot is running at high load and high speed, the hypothesized mode method is adopted to discretize the follower arm member. Based on Kane equation and augmented Lagrange multiplier method, the rigid-flexible coupling dynamic equation of Delta parallel robot system is established, and the influence of follower arm deformation on robot positioning accuracy is quantified. By comparing the results of ADAMS model simulation and MATLAB numerical analysis under the same tracking trajectory, the trajectory of the moving platform's center of mass basically coincides and the rotation Angle deviation of the active joint is less than 0.01 rad, which verifies the correctness of the rigid-flexible coupling dynamic equation and provides theoretical support for the precise control of the robot. Finally, through numerical analysis and Adams-Matlab co-simulation analysis, the maximum displacement offset of the end moving platform in the X and Z directions and the maximum deviation of the driving torque of the active joint are obtained under different load conditions. The simulation results reflect the law of the influence of the flexibility of the follower arm on the dynamic performance of the robot.

Key words: Delta robot, high speed and heavy load, rigid-flexible coupling, Kane equation, dynamic modeling