Robust H∞ control of a traction drive system for precision motion

The control system for a traction drive must produce robust response with respect to a change in the mass of the workpiece on the slide. It has been found that a conventional controller cannot tolerate a large range of mass change. In this paper, a discrete-time H_∞ controller is described that has achieved robustness with respect to a change in mass. Comparison between the robustness of two controllers, PID and H_∞, is given by the experimental results and shows the improvement using the H_∞ controller.