Actuator and Sensor Fault Reconstruction Using an LPV Sliding Mode Observer

Abstract

This paper presents a new actuator and sensor fault reconstruction scheme for Linear Parameter Varying (LPV) systems, based on a sliding mode observer. Two separate observer schemes for actuator and sensor fault reconstruction are presented. For the design of the actuator fault reconstruction scheme, the varying input distribution matrix has been factorized into a fixed and a varying component. A virtual system comprising the system matrix and the fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix facilitates a coordinate transformation which defines the observer gains and ensures a stable closed-loop reduced order sliding motion. The 'output error injection signals' from the observer are used for reconstruction. For the sensor fault design, augmenting the LPV system with a filtered version of the faulty measurements allows the problem of sensor fault reconstruction design to be posed as an actuator fault reconstruction problem. Simulation tests based on an LPV and high-fidelity model of a large transport aircraft have been used to demonstrate the proposed actuator and sensor FDI scheme. The simulation results show good reconstruction of the faults for both actuator and sensors. Nomenclature 6-DOF = 6 degree of freedom F DI, F T C = Fault detection and isolation, fault tolerant control LT I, LP V = Linear time invariant, linear parameter varying cmd = command signal mac = mean aerodynamic chord q = pitch rate V tas = true air speed α, θ, γ = angle of attack, pitch, flight path angle h e = geometric earth position along the z (altitude) axis IR = field of real numbers R(A) = range space of the matrix A ρ = LPV parameter

Sliding mode control design of an electrostatic microactuator using LPV schemes

“…As mentioned in Section IV-B, the design of the observer gains are dependent on L 1 in (28). Similar to the controller design, L 1 is obtained as part of the output of the standard MATLAB LMI multi-model state feedback synthesis code 'msfsyn' [32] adapted to tackle an observer problem (using the dual property of the standard control problem).…”

Nullspace-Based Input Reconfiguration Architecture for Overactuated Aerial Vehicles

“…Suppose that u G, (or equivalently f ) is available for measurement or can be reconstructed by a suitable FDI filter, e.g. [21]. LetĀ be an n u input -n u output LTI shaping filter defined later and let N be the (stable) generator for the nullspace of G•A•Ā.…”

Development and application of sliding mode LPV fault reconstruction schemes for the ADDSAFE Benchmark

“…However recently higher order sliding mode methods have be employed to develop so-called interval observers [15], and an LPV observer has been proposed in a fault detection context [16]. The scheme first proposed in [16] considers pole placement methods to assign the design freedom. Subsequently the sensor fault reconstruction scheme employed in this paper, based on a more advanced approach, was developed in [17].…”