This paper deals with the robust fault detection(FD) problem in low frequency domain for linear timedelay systems. The H∞ norm and H− index are employed to measure the robustness to unknown inputs and the sensitivity to faults, respectively. The main results include derivation of a sufficient condition for the existence of a robust fault detection observer and a construction of it based on the ...

A common requirement implicit in current methods for the design of robust state estimators and robust fault detection filters is that the first Markov matrix must be non-zero, and indeed, full rank. We relax both of these restrictions in this paper to allow the applicability to a wider range of systems. The extended results are then applied to an aircraft fault detection for which the restricti...

This paper investigates the problem of robust fault detection observer design for nonlinear Takagi–Sugeno models with unmeasurable premise variables subject to sensor faults and unknown bounded disturbance. The main idea is to synthesize a robust fault detection observer by means of a mixed H =H1 performance index. The considered observer is used to estimate jointly states and faults. Using the...

This paper considers the robust fault detection and isolation (FDI) problem for uncertain linear timeinvariant (LTI) systems. An FDI filter minimizes the sensitivity of the residual signal to disturbances and modeling errors subject to the constraint that the transfer matrix function from the faults to the residual is close to a diagonal matrix (for fault isolation). A solution of the optimizat...

The paper addresses the problem of designing a robust fault detection filter for an uncertain Takagi-Sugeno fuzzy models. The existence of a robust fault detection filter that guarantees i) the L2-gain from an exogenous input to a residual signal is less than a prescribed value and ii) the L2-gain from a fault signal to a residual signal is greater than a prescribed value is given in terms of t...

A robust control allocation scheme is developed for rigid spacecraft attitude stabilization in the presence of actuator partial loss fault, actuator failure, and actuator misalignment. First, a neural network fault detection scheme is proposed, Second, an adaptive attitude tracking strategy is employed which can realize fault tolerance control under the actuator partial loss and actuator failur...

We present a novel approach for model-based FDI of abrupt faults in process components of continuous dynamic systems. Abrupt faults refer to parameter value changes that occur much faster than the nominal process dynamics, and component faults refer to faults that correspond to physical parameters in the bond graph model of a system. These faults cause transients in system behavior. We analyze ...