Redundant manipulator for obstacle avoidance and inverse kinematics solution by least squares

An 8 degree-or-freedom (DOF) redundant manipulator is designed and realized for uses in robot-human environments requiring obstacle avoidance. The extra two DOF provides the flexibility in kinematics for obstacle avoidance. The modular mechanical structure associates both simple mechanical construction and an easy forward kinematics solution. A motor-control module is implemented to perform a constant acceleration motion in accordance with the commands from a host computer. The inverse kinematics solution of the redundant manipulator is introduced by using the forward kinematics with the recursive least squares estimation (RLSE) method. The RLSE method is applied for the linearized model of the nonlinear kinematics around the operating point