A vibration suppression method for flexible joints manipulator based on trajectory optimization

How to reduce the vibration deformation of robot manipulators with flexible joint is a significant problem. A new approach based on simplified system dynamic model and genetic algorithms (GA) is developed to find an optimized trajectory in joint space for a three degrees-of-freedom plane flexible joints manipulator, to reduce the residual vibration of the robot on the occasion of fast position control. The method makes the strain energy stored in the flexible joints minimized through planning the links and joint motors arrive at the destination positions simultaneously, so the residual vibration would be suppressed accordingly. And a genetic algorithm, whose objective function is to minimizing the maximum elastic deformation of the robot joints, was used to find the global optimized desired trajectory. And the computer simulation results show that the proposed method, comparing with the traditional trajectory planning method based on inverse kinematics calculation, reduces the trajectory tracing error and the residual vibration amplitude considerably.