Generation of stable oscillations in uncertain nonlinear systems with matched and unmatched uncertainties

2017 ◽  
Vol 92 (1) ◽  
pp. 163-174 ◽  
Author(s):  
A. R. Hakimi ◽  
T. Binazadeh
Keyword(s):  
Nonlinear Systems ◽  
Uncertain Nonlinear Systems ◽  
Unmatched Uncertainties ◽  
Matched And Unmatched Uncertainties

scholarly journals Design of Robust Supertwisting Algorithm Based Second-Order Sliding Mode Controller for Nonlinear Systems with Both Matched and Unmatched Uncertainty

Complexity ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Marwa Jouini ◽  
Slim Dhahri ◽  
Anis Sellami
Keyword(s):  
Nonlinear Systems ◽  
Sliding Mode ◽  
Sufficient Conditions ◽  
Mode Switching ◽  
Pendulum System ◽  
Novel Structure ◽  
Loop Feedback ◽  
Unmatched Uncertainties ◽  
Closed Loop Feedback ◽  
Matched And Unmatched Uncertainties

This paper proposes a robust supertwisting algorithm (STA) design for nonlinear systems where both matched and unmatched uncertainties are considered. The main contributions reside primarily to conceive a novel structure of STA, in order to ensure the desired performance of the uncertain nonlinear system. The modified algorithm is formed of double closed-loop feedback, in which two linear terms are added to the classical STA. In addition, an integral sliding mode switching surface is proposed to construct the attractiveness and reachability of sliding mode. Sufficient conditions are derived to guarantee the exact differentiation stability in finite time based on Lyapunov function theory. Finally, a comparative study for a variable-length pendulum system illustrates the robustness and the effectiveness of the proposed approach compared to other STA schemes.

Finite-time terminal synergetic control of a class of nonlinear systems with unmatched uncertainties

2019 ◽  
Vol 37 (3) ◽  
pp. 765-776 ◽  
Author(s):  
Azadeh Ahifar ◽  
Abolfazl Ranjbar Noei ◽  
Zahra Rahmani
Keyword(s):  
Nonlinear Systems ◽  
Finite Time ◽  
Tracking Error ◽  
Lyapunov Theory ◽  
Uncertain Nonlinear Systems ◽  
Unmatched Uncertainties ◽  
Synergetic Control ◽  
The Stability

Abstract In this paper, the problem of finite-time tracking for nth-order uncertain nonlinear systems with unmatched uncertainties is addressed. Using a terminal synergetic manifold, a controller is provided to force the tracking error to the origin in finite time in the presence of unmatched uncertainties. With this method, chattering problem is completely removed without defining a new function. Lyapunov theory is used to prove the stability of the proposed method. The proposed controller provides the convergence of finite-time tracking error to zero by suitable performance that is theoretically analysed and proved through simulation.

Sign in / Sign up

Export Citation Format

Share Document