A solution of inverse kinematics for 7-DOF manipulators and its application

This paper provides a solution of inverse kinematics for 7-DOF manipulators, which is derived by homogeneous transformation matrix described in equivalent angle-axis representation. The end-effector´s posture calculated by this approach has excellent precision. The manipulator can avoid collision and singularity while meeting the parameters of the joints through the optimization of the redundancy. Moreover, in order to increase the comfort level of the arm, we improve the method based on Jacobian pseudo-inverse to calculate the angular velocity. The time it takes is so short that it can be applied to on-line application. We applied this method to a manipulator of a ping-pong robot and proved its validity.