L₁ impedance control for bilateral teleoperation containing model uncertainty

Abstract

Restricting transient peaks of contact force in teleoperation systems is undeniably vital, specially in critical applications such as telesurgery. This issue, however, has still remained unsolved in the literature. In order to address this problem, we propose an impedance control scheme using optimal L1 theory for teleoperation systems encompassing asymmetric randomly time-varying delays and model uncertainties. To this end, an L1-based state-feedback compensator is designed employing linear matrix inequalities, aiming at minimizing the desired impedance error subjected to human force as exogenous disturbance. A simulation is ultimately conducted in comparison with the sliding-mode-based impedance controller. The results validate that the proposed controller is able to keep the integral of impedance error within the desired bound and, thus, improves the transient response. This is, however, at the expense of imposing a steady-state error for the integral of impedance error, which is normally made zero by the sliding-mode controller.

Simple recognition of hand gestures using single-channel EMG signals

“…We suggest looking at more features, classification techniques, and gesture types in future research. Furthermore, control techniques could be greatly simplified by utilizing gesture recognition in teleoperation systems, 40,41 which are frequently employed for remote control. Finally, due to the different number of participants for male and female subjects in this study, it can be seen and investigated under the gender imbalance problem which we consider it as a future direction of this study.…”