Sliding-Mode Control of a Class of Nonlinear Systems in the Presence of Input Saturation

Abstract

In this paper, we present a sliding-mode control approach for a two-order nonlinear system in the presence of input saturation and external disturbance. A robust control algorithm is constructed by using backstepping design techniques. Two well-defined smooth functions are introduced to approximate the primary functions so that they could be differential. To overcome the problem of input saturation, a new auxiliary design system and a Nussbaum function are incorporated into the control method. It is proved that the global stability of the closed-loop system can be guaranteed by the proposed control algorithm. A simulation example is included at last.

Optimal sliding‐mode control of linear systems with uncertainties and input constraints using projection neural network

“…Using (14), ∇f(u, t) = W(t)u(t) + h(x, t). Moreover, based on (19), h(x, t). Hence, one can get ∇f(u * , t) = χ * .…”

“…An adaptive back‐stepping SMC‐based method that is called the command‐filtered approach was proposed by Hongmei and Guoshan to encounter the input constraints. The saturation function as a discrete description of the input limits was employed by Liu and Pi . The main problem of these methods is that there is no systematic approach to handle constraints on the control signals.…”

“…The saturation function as a discrete description of the input limits was employed by Liu and Pi. 19 The main problem of these methods is that there is no systematic approach to handle constraints on the control signals. In addition, the stability analysis is complicated, as compared with other approaches.…”