Abstract: A redundant robot is designed to achieve automatic inner surface spraying operation for bent pipe. Since the low system stiffness of the redundant robot, vibrations occur during the spraying process, which increase terminal tracking error and influece the quality of the coating. To this end, this article builds dynamic equations of redundant robot with the influence of elastic deformation and proposes a trajectory optimization method, which can optimize the joints trajectory to reduce vibrations and satisfy workspace constraints. In the experiments, as the trajectory satisfy the complex work-space constraints, the vibrations is suppressed by using the optimization trajectory planning method. Thus, the effectiveness of the trajectory optimization method is proved.

Key words: Redundant robot, Trajectory optimization, Vibration suppression