Prescribed performance output feedback synchronisation control of bilateral teleoperation system with actuator nonlinearities

This work investigates output feedback synchronisation control of uncertain bilateral teleoperation system with synchronisation error constraints, time-varying delay, actuator backlash-like hysteresis and unknown control direction. The constrained system is transformed into unconstrained one via the output error transformation. A Prescribed-Performance Function (PPF) is proposed to ensure that all the outputs with predefined transient and steady states' performances converge to a predefined set. In addition, a radial basis function neural network (RBFNN) is utilised to estimate the uncertain dynamics. Moreover, a Nussbaum-type function is introduced to tackle the loss of control direction due to the actuator backlash-like hysteresis. By Lyapunov stability analysis, all the closed-loop signals are guaranteed to converge to a small neighbourhood of the origin. Finally, simulation results are provided to demonstrate the effectiveness of the proposed method.