Dynamic-Boundary-Layer Based Nonlinear Robust Control for Robotic Systems

Through reducing the boundary layer, higher control accuracy can be achieved when applying robust control techniques. However, chattering phenomenon may occur. This paper presents a nonlinear robust controller design in which a dynamic boundary layer is introduced. Theoretical results are presented for characterizing the tracking performance. In particular, the tracking error is forced to converge to the pre-specified boundary layer so that the control accuracy is achieved, while the chattering phenomenon is alleviated. The effectiveness of the proposed control method is demonstrated by the presented numerical results.