Nonlinear PD-type control in position domain

In this paper, a nonlinear PD-type control law is proposed in position domain and applied to contour tracking control of a robotic manipulator. In the developed control system, the robotic motions are viewed as a master motion, controlled in time domain, and slave motions controlled in position domain. The master motion is used as a reference for the slave motions, and the slave motions are synchronized with the master motion so that a good contour tracking performance can be obtained. Different type contour tracking problems are simulated and compared with existed controllers. It is demonstrated that the nonlinear PD-type position domain control can achieve better contour tracking performance compared with the counterparts in time domain and the linear PD-type position domain control.