Controlling a rotary servo cart system using robust generalized dynamic inversion

This paper presents the design and implementation of the Robust Generalized Dynamic Inversion (RGDI) based position and speed control of the rotary servo cart system. The RGDI control law comprises the two sub-parts, i.e., the equivalent control part and the robust control part. The equivalent control part represents the conventional form of the Generalized Dynamic Inversion control, in which dynamical constraints based on the deviation functions of angular position and its rate are formulated that encapsulates the control objectives. The control law is realized by inverting the constraint dynamics using dynamically scaled generalized inversion. The robust control part consists of an additional term based on the sliding mode principle that makes the control law robust with respect to the parametric fluctuation and outward disturbances while providing improved tracking performance. The closed-loop stability of RGDI control is ensured using the positive definite Lyapunov candidate function, which will guarantee globally practical stable tracking performance. Numerical simulations in Matlab/Simulink environment and the real-time experiments are performed on the Quanser's SRV02 rotary servo cart platform. It exhibits better tracking performance through simulation and the experimental results. Robustness attributes to the proposed control law under the influence of the parametric uncertainties and external disturbances.