Position tracking and force control of robotic manipulators with a descriptor system model. II. The exact control and a control strategy based on LQ method

In this paper, the problem of position tracking and contact force control for a constrained manipulator, the end effector of which is required to move along a preassigned trajectory with a specified contact force, is studied. Two control schemes are presented. The first scheme provides exact control. The second scheme is based on a linear descriptor system, obtained by applying nonlinear feedback from the nonlinear descriptor system, using an LQ synthesis method. The basic procedure for controller design is divided into two steps: first, the nonlinear descriptor system is linearized into a linear system; then various control schemes for different cases are proposed based on the resultant linear model