Zero-error tracking control of uncertain nonlinear systems in the presence of actuator hysteresis

Abstract

In this paper, the problem of adaptive tracking control is addressed for a class of nonlinear systems with unknown constant parameters and unknown actuator nonlinearity. The actuator nonlinearity is modelled as the backlash-like hysteresis, which is described by a differential model. The prior knowledge on the control gain sign is not required, and only the assumption on the reference signal is made. By combining the adaptive backstepping technique with the Nussbaum gain approach, an adaptive compensation controller design approach is developed. It is proved that the proposed control approach can guarantee that all the signals in the closed-loop system are bounded, and the tracking error can converge to zero asymptotically despite the presence of the actuator hysteresis. Two simulation examples are included to illustrate the effectiveness of the proposed approach.

Stabilization of a class of upper-triangular systems without a priori knowledge of control directions under the homogeneous domination

“…When the uncertain system function satisfies certain conditions, the output problems of a class of time-varying uncertain nonlinear systems with unknown control coefficients is investigated in . The problem of adaptive tracking control is addressed in Zhang et al (2014) for a class of nonlinear systems with unknown constant parameters and unknown actuator nonlinearity.…”