Improved Adaptive Sliding Mode Control for a Class of Uncertain Nonlinear Systems Subjected to Input Nonlinearity via Fuzzy Neural Networks

Abstract

The paper presents an improved adaptive sliding mode control method based on fuzzy neural networks for a class of nonlinear systems subjected to input nonlinearity with unknown model dynamics. The control scheme consists of the modified adaptive and the compensation controllers. The modified adaptive controller online approximates the unknown model dynamics and input nonlinearity and then constructs the sliding mode control law, while the compensation controller takes into account the approximation errors and keeps the system robust. Based on Lyapunov stability theorem, the proposed method can guarantee the asymptotic convergence to zero of the tracking error and provide the robust stability for the closed-loop system. In addition, due to the modification in controller design, the singularity problem that usually appears in indirect adaptive control techniques based on fuzzy/neural approximations is completely eliminated. Finally, the simulation results performed on an inverted pendulum system demonstrate the advanced functions and feasibility of the proposed adaptive control approach.

Adaptive sliding mode control for fuzzy singular systems with time delay and input nonlinearity

“…Therefore, the input nonlinearities can deteriorate the systems' performances and their effects must be taken into account in analyzing and designing any control scheme. Recently, attention has been paid to input nonlinearity, [27][28][29][30][31] but few works have been undertaken for singular systems.…”

Robust H∞ Control for Nonlinear Uncertain Switched Descriptor Systems with Time Delay and Nonlinear Input: A Sliding Mode Approach

“…So, their effects cannot be ignored in analysis design. In recent years, much attention has been paid to the input nonlinearity [24][25][26][27][28][29], but, to the best of our knowledge, the problems of (SMC) for switched descriptor systems subjected to time-varying delay and input nonlinearity have not been fully investigated and still remain open and challenging. This has motivated the present study compiled in this paper.…”

Finite‐time exact tracking control for a class of non‐linear dynamical systems

“…However, it should be pointed out that most of non‐singular TSMC methods are available only for second‐order systems [17–19]. Recently, a limited number of non‐singular TSMC schemes are proposed for higher order systems [20–22], but these non‐singular TSMC schemes are only suitable for integral cascade high‐order non‐linear systems. Therefore, non‐singular TSMC of non‐integral cascade high‐order non‐linear systems needs to be investigated by a new technique.…”