Motion Planning of Sampling Flexible Manipulator on Planet

In order to adapt to a wide range of planetary surface sample acquisition and requirements of weight optimization, manipulator usually consists of several slender arms and rotary joints. This makes the flexibility compensation and vibration suppression become research focus in the manipulator control system. In this paper, a smooth trajectory planning method with parabolic contour for sampling motion of manipulator is proposed. In the motion process acceleration is made to be continuous to avoid joint torque mutation and debase the peak value farthest. Firstly, the kinematic equations of manipulator based on D-H and dynamics model with flexible deformation of joints and arms are established. Then, the variable acceleration-uniform motion-deceleration trajectory is planned in Cartesian space, which acceleration is consistent and smooth. Finally, the typical tasks of manipulator are simulated. Results indicate that this method is useful to make acceleration of joint motion continuous. This control strategy can obviously improve dynamic tracking accuracy and position precision.