Self-tuning fuzzy nonsingular proportional-integral-derivative type fast terminal sliding mode control for robotic manipulator in the presence of backlash hysteresis

Abstract

The external disturbances and backlash hysteresis kind of nonlinearity present in the manipulator system can greatly affect the tracking performance of the system. In order to undo the effects of these external disturbances and backlash hysteresis, a robust controller is established based on the integration of self-tuning fuzzy nonsingular proportional-integral-derivative (PID) type fast terminal sliding mode control and time delay estimation (TDE). In this paper, TDE plays the part of estimating the unknown dynamics of the robotic manipulator and nonsingular PID type fast terminal sliding mode control in which the gains of PID are tuned using fuzzy logic system to get multiple beneficial characteristics, such as lower steady-state error, finite-time convergence and little chattering. In addition, the derivative of unknown dynamics that is considered to be bounded is dealt by utilizing the adaptive technique. Moreover, Lyapunov theorem is used to study the overall stability of the system. Finally, a comparative study in terms of trajectory tracking has been carried out between the proposed controller and other existing advanced control approaches using PUMA560 robot in order to verify the effectiveness of the proposed controller in the presence of external disturbances and bacsklash hysteresis.