Stabilization of underactuated mechanical systems with time-varying uncertainty using adaptive fuzzy sliding mode

Abstract

In this paper, the control problem of underactuated systems in the presence of external disturbances and time varying model uncertainties is considered. Ensuring the stability and robust performance against uncertainties and disturbances arc the main problems in such systems. An adaptive fuzzy sliding mode controller (AFSMC) is proposed to solve the problem, satisfying the robustness properties against the perturbations. The designed controller can be applied to a wide class of underactuated systems with fewer restrictions, compared with many pervious works. To evaluate the performance of proposed algorithm, it is applied to an underactuated inverted pendulum and a Translational Oscillator/Rotational Actuator (TORA) system with two degrees of freedom. The simulation results are compared with a conventional method to demonstrate the effectiveness of the proposed strategy. The results show that the proposed controller guarantees the stability and robustness against time varying uncertainties and disturbances. Copyright © 2014 SoftMotor Ltd.