Robust fault tolerant control based on adaptive observer for Takagi-Sugeno fuzzy systems with sensor and actuator faults: Application to single-link manipulator

Abstract

In this work, we investigate the problem of control for nonlinear systems represented by Takagi-Sugeno (T-S) fuzzy models affected by both sensor and actuator faults subject to an unknown bounded disturbances (UBD). For this, we design an adaptive observer to estimate state, sensor and actuator fault vectors simultaneously despite the presence of external disturbances. Based on this observer, we develop a fault tolerant control (FTC) law not only to stabilize closed loop system, but also to compensate the fault effects. For the observer-based controller design, we propose less conservative conditions formulated in terms of linear matrix inequalities (LMIs). Moreover, both observer and controller gains are calculated via solving a set of LMIs only in single step. Finally, comparative results and an application to single-link flexible joint robot are afforded to prove the efficiency of the proposed design.

Adaptive PID Fault-Tolerant Tracking Controller for Takagi-Sugeno Fuzzy Systems with Actuator Faults: Application to Single-Link Flexible Joint Robot

“…Adaptive Fuzzy Observer (7) based fault tolerant tracking control (8) has been designed for nonlinear systems represented by T-S fuzzy models affected by actuator faults and external disturbances. First of all, the AFO can estimate system states and actuator faults accurately.…”

“…where, 𝐽 𝑚 represents the inertia of the motor, 𝐽 𝑙 is the inertia of the controlled link, 𝑚 is the link mass, ℎ is the center of mass, 𝑔 is the acceleration due to gravity, 𝑘 is the elastic constant, 𝐵 𝑣 is the viscous friction coefficient and 𝐾 𝜏 is the amplifier gain. The numerical values of these parameters are listed in Table 1 [8].…”

Robust fault estimation and fault‐tolerant tracking control for uncertain Takagi–Sugeno fuzzy systems: Application to single link manipulator

“…Yet, this method need a high additional computational cost. Authors in References 18 and 19 have investigated the control problem for T‐S systems in presence of SAF. However, in many practical systems, the main objective is to develop a fault tolerant control not only for the compensation of fault effects and the stabilization but also to drive system states to track the desired states of the reference model.…”

Robust Static Output-Feedback Fault Tolerant Control for a Class of T-S Fuzzy Systems using Adaptive Sliding Mode Observer Approach

“…However, this method is more expensive since it requires a high additional computation cost. In [24], a robust adaptive observer is developed to simultaneously estimate state and both sensor and actuator faults for nonlinear systems despite the presence of disturbances. A FTC law is applied to stabilize the closed-loop system and compensate the fault effects.…”

“…2. Most existing SMO design methods such as those reported in [22][23][24] assume that the value of the upper bounds of actuator faults ρ a and sensor faults ρ s is known. If the information of fault is unknown or exceeds the admissible value, these methods cannot be feasible.…”