Nonlinear kinematic control for a robotic system with high redundancy

A nonlinear kinematic control developed for a nine-joint robotic manipulator designed for car-interior assembly applications is described. The three degrees of redundancy are fully utilized to achieve three independent performance criteria: avoidance of rotational singularity, even distribution of joint static torques, and translational singularity avoidance. A complete state-feedback kinematic control algorithm is developed through exact linearization and internal kinematics analysis. Three potential functions are modeled as the system output, and the weights of null space vectors are viewed as the system input, while the forward Jacobian equation represents the internal kinematics. The stability and major performance of the entire kinematic control system are discussed and demonstrated by a simulation study