Towards Prescribed Accuracy in Under-tuned Super-Twisting Sliding Mode Control Loops -- Experimental Verification

Obtaining prescribed accuracy bounds in super-twisting sliding mode control loops often falls short in terms of the applicability of the controller in high-performance systems. This is due to the fact that the selection of the controller gains that are derived from the conditions for finite-time convergence may be too restrictive in connection to actuator limitations and induced chatter. Previous work has shown that in case of periodic perturbations, there can be a systematic selection of much lower controller gains that guarantees boundedness of the closed-loop solutions within predetermined accuracy bounds. This study presents an experimental validation of these findings carried out on a commercial industrial motor system.