Joint parameter identification of a moving flexible joint robot

A new approach to identify joint parameters of a flexible joint robot under movement was presented.Firstly,taking a flexible joint as an elastic twist axis,and combining the wave theory of structures with the rotating transformation matrix of a joint,the wave equations of the mechanism were established.Secondly,considering general force balance of all nodes and displacement boundary of each joint,the environmental prediction model of the system under moving states was deduced.Furthermore,the vibration equations were gained according to the predicted excitations and the tested joint twist angles.Thirdly,joint dynamic stiffness and damping were deduced after solving the former model by use of the least square method(LSM).Finally,parameters identification experiments of a 3-DOF manipulator were done under two different move trajectories.The experimental results showed that the proposed approach is effective and it can provide a reference for the further dynamic control.