Dynamic analysis of a hexapod robot with parallel leg mechanisms for high payloads

A novel hexapod robot with 3-DOF parallel leg mechanisms is presented in this paper. The payload capability of the robot has a high promotion due to the utilizing of parallel mechanisms. Meanwhile, a novel force distribution approach of joint space distribution for redundant actuation system is proposed to optimize joint forces in order to promote the payload capability of the robot. Usually, the dynamic load of the robot is distributed over the contact space, then map the forces of contact space onto joint space. Different to the usual way of contact space distribution, in this paper, the optimal force distribution for the supporting legs is directly solved in the joint space using the Moore-Penrose pseudo-inverse matrix. The simulation results demonstrate that the joint space distribution scheme results in a much more efficient distribution compared with the conventional scheme of contact space distribution due to the good use of friction to reduce the required joint forces.