학술논문
Disturbance-observer Based Adaptive Control for Second-order Nonlinear Systems Using Chattering-free Reaching Law
Document Type
Article
Author
Source
(2022): 356-369.
Subject
Language
Korean
ISSN
15986446
Abstract
In this paper, an adaptive sliding mode control incorporating with a nonlinear disturbance observer isproposed for a class of second-order nonlinear systems with unknown parameters and matched lumped disturbance. A double hyperbolic reaching law with chattering-free characteristic is first constructed, and an adaptive slidingmode controller is designed to guarantee the satisfactory tracking performance and fast error convergence. Thechattering problem is eliminated by means of the infinitely approaching equilibrium point instead of crossing it byemploying two hyperbolic functions. In order to identify the unknown parameters accurately, an adaptive parametricupdate law is presented through constructing a set of auxiliary filtered variables. Then, a nonlinear disturbanceobserver is proposed to improve the tracking performance and compensate for the lumped disturbance includingperturbations and uncertainties. The stability analysis is provided by the Lyapunov stability theory, and a numericalsimulation on a mass-spring damper system is given to demonstrate the effectiveness of the proposed method.
In this paper, an adaptive sliding mode control incorporating with a nonlinear disturbance observer isproposed for a class of second-order nonlinear systems with unknown parameters and matched lumped disturbance. A double hyperbolic reaching law with chattering-free characteristic is first constructed, and an adaptive slidingmode controller is designed to guarantee the satisfactory tracking performance and fast error convergence. Thechattering problem is eliminated by means of the infinitely approaching equilibrium point instead of crossing it byemploying two hyperbolic functions. In order to identify the unknown parameters accurately, an adaptive parametricupdate law is presented through constructing a set of auxiliary filtered variables. Then, a nonlinear disturbanceobserver is proposed to improve the tracking performance and compensate for the lumped disturbance includingperturbations and uncertainties. The stability analysis is provided by the Lyapunov stability theory, and a numericalsimulation on a mass-spring damper system is given to demonstrate the effectiveness of the proposed method.
In this paper, an adaptive sliding mode control incorporating with a nonlinear disturbance observer isproposed for a class of second-order nonlinear systems with unknown parameters and matched lumped disturbance. A double hyperbolic reaching law with chattering-free characteristic is first constructed, and an adaptive slidingmode controller is designed to guarantee the satisfactory tracking performance and fast error convergence. Thechattering problem is eliminated by means of the infinitely approaching equilibrium point instead of crossing it byemploying two hyperbolic functions. In order to identify the unknown parameters accurately, an adaptive parametricupdate law is presented through constructing a set of auxiliary filtered variables. Then, a nonlinear disturbanceobserver is proposed to improve the tracking performance and compensate for the lumped disturbance includingperturbations and uncertainties. The stability analysis is provided by the Lyapunov stability theory, and a numericalsimulation on a mass-spring damper system is given to demonstrate the effectiveness of the proposed method.