Prescribed performance control of one-DOF link manipulator with uncertainties and input saturation constraint

In this paper, we mainly address the position control problem for one-degree of freedom ( DOF ) link manipulator despite uncertainties and the input saturation via the backstepping technique, active disturbance rejection control ( ADRC ) as well as predefined tracking performance functions. The extended state observer ( ESO ) is employed to compensate uncertain dynamics and disturbances, and it does not rely on the accurate model of systems. The tracking differentiator ( TD ) is utilized to substitute the derivative of the virtual control signals, and the explosion of complexity caused by repeated differentiations of nonlinear functions is removed. The auxiliary system is used to deal with the control input limitation, and the tracking accuracy and speed are improved by predefined tracking performance functions. With the help of the input-to-state stability ( ISS ) and Lyapunov stability theories, it is proven that the tracking error can be gradually converged into arbitrarily small neighborhood of the origin, and the tracking error is adjusted by suitable choice of control parameters. The simulation results are presented for the verification of the theoretical claims.