Nonlinear PD control for trajectory tracking with consideration of the design for control methodology

This paper presents a study of examining nonlinear PD (NPD) control of multi-degree-of-freedom parallel manipulator systems for a generic task, i.e., trajectory tracking. The motivation of this study is the well-known observation that NPD control method can offer a means to improve the performance of plant systems. This study is also to examine how the mechanical structure of the manipulator affects dynamic performance. The design of mechanical structure follows the design-for-control (DFC) principle, and in particular it renders to a full force balanced mechanism. Simulation studies confirm that the concurrent consideration of mechanical structure design and NPD control can obtain good trajectory tracking performance for the parallel manipulators.