Modified scheme of PID controllers for robot manipulators with an uncertain Jacobian matrix

Performance and robustness of the traditional PID controllers are both limited since only three parameters are available to tune in controller design. A new modified scheme of PID controller is proposed in this paper for Cartesian regulation of robot manipulators with uncertain Jacobian matrix, in which the integral action is adapted to error amplitude. The proposed controller improved performance and robustness of the resulting system significantly and it is demonstrated by simulation comparison with the traditional one.