A Study on the Plant-Input-Mapping Discretization for Nonlinear Control Systems Utilizing Feedback Linearization

This study attempts to extend a digital redesign method, called the Plant-Input-Mapping (PIM) method, to nonlinear control systems. The PIM method in the linear case can preserve the stability of the underlying continuous-time feedback control system without respect to the selection of the sampling interval. The PIM method is a model-based approach, and thus, the key of the extension scheme is to overcome the absence of the exact discrete-time model for nonlinear systems. In this paper, we propose a PIM method incorporating the feedback linearization. The proposed method can discretize the continuous-time controller designed by using the linearization technique, which is numerically verified through an example of a robotic manipulator with a flexible joint.