Robust control-based disturbance observer and optimal states feedback for T–S fuzzy systems

Abstract

This paper presents a robust control methodology based on a disturbance observer and an optimal states feedback for Takagi–Sugeno fuzzy system. Firstly, the nonlinear systems were solved by applying a sector nonlinearity method to get the inner linear subsystems and outer fuzzy membership functions, which guaranteed the conversion without any loss generality characteristics of the system. Secondly, an exponentially convergent disturbance observer was constructed to the system with an assumption that the system states are temporarily bounded. Thirdly, a states observer was built by poles placement of linear quadratic regulation optimization, which was used to place the system states error poles located on the stable region. Finally, simulation examples were given to figure out that the proposed controller is effective to control the Takagi–Sugeno fuzzy system. The obtained results are disturbance mostly rejected, state estimation errors are quite small, and the output signal precisely tracked input signal.

Robust Sliding Mode Control-Based a Novel Super-Twisting Disturbance Observer and Fixed-Time State Observer for Slotless-Self Bearing Motor System

“…The proposed DOB can estimate perturbations in many different formats. There is no need the prior format of the perturbations such as [22][23][24]. This is a huge suggestion for future direction of the area of disturbance rejection control design.…”

“…In our developments of nonlinear disturbance observers in [19][20][21] still need some conjunctions of parameters. Or some disturbance observers just only can be used to estimate the fixed format of disturbance value such as [22][23][24]. This paper aims to provide a new super-twisting DOB for the SSBM system with simple structure and simple condition.…”

Inversed Model-Based Disturbance Observer Base on Adaptive Fast Convergent Sliding Mode Control and Fixed-Time State Observer for Slotless Self-Bearing Motor

“…The development of nonlinear DOB can be found in [25][26][27]. Otherwise, the DOB for a fixed disturbance format can be found in [28][29][30]. In fact, the format and frequency of unknown disturbances cannot be predefined.…”

Robust Observer Based on Fixed-Time Sliding Mode Control of Position/Velocity for a T-S Fuzzy MEMS Gyroscope

“…T-S fuzzy modeling of the nonlinear system was investigated in detail as sector nonlinearity and linearization by Tanaka and Wang [14]. The development of T-S fuzzy modeling was described in previous papers [15][16][17][18][19][20][21][22]. By using the T-S fuzzy model, the mathematical model of a MEMS gyroscope can be changed into the combination of four fuzzy membership functions and four sublinear systems.…”