Fault Tolerant Control Using Sliding Modes with On-Line Control Allocation

Abstract

This paper proposes an on-line sliding mode control allocation scheme for fault tolerant control. The effectiveness level of the actuators is used by the control allocation scheme to redistribute the control signals to the remaining actuators when a fault or failure occurs. The paper provides an analysis of the sliding mode control allocation scheme and determines the nonlinear gain required to maintain sliding. The on-line sliding mode control allocation scheme shows that faults and even certain total actuator failures can be handled directly without reconfiguring the controller. The simulation results show good performance when tested on different fault and failure scenarios.

Integral Sliding Mode Fault‐Tolerant Control for Spacecraft With Uncertainties and Saturation

“…Alwi et al [11][12][13] have proposed that the relationship between the actual efficiency matrix W (t) and its estimateŴ (t) should satisfy…”

“…In their research, the effects of two types of unmatched uncertainties, both L 2 and L 2 ⋂ L ∞ , to the sliding surface are explored, achieving a uniform boundedness or asymptotic stability. ISM has been applied to fault tolerant control by H. Alwi, et al [11][12][13]. Pseudoinverse for control allocation (CA), ISM, and efficiency parameter identification are included and applied to an aircraft model.…”

Networked Fault-Tolerant Control Allocation for Multiple Actuator Failures

“…In this figure, for a virtual-input signal v( ) ∈ R generated by the controller, the control allocator generates the corresponding real control input signal u( ) ∈ R . For the dynamical system represented in (7) with ,min ≤ ≤ ,max , suppose that the equivalent system controlled by the virtual input is represented as follows:ẋ…”

“…However, adopting redundant actuators takes disadvantages of fuel-, space-, cost-, and weightinefficiency during normal operation. In contrast to adopting redundant actuators, techniques based on control theory have been proposed for last 30 years: for example, pseudoinverse [1], model reference adaptive control [2], sliding mode control [3], multiple model switching and tuning [4], control allocation [5][6][7][8][9][10], and so forth. The goal of these methods is to provide the feasible control input for a faulty system by reconfiguring a controller.…”

IMMUNE : Control reallocation after surface failures using model predictive control

“…All solutions use basically either weighting pseudo-inverse approach or linear/quadratic optimizations [5,2]. Improvements can be reached through multiple allocation step schemes like Daisy Chaining [3] or through combinations with other techniques (sliding modes control...) [1]. In [6] Model Predictive Control addresses a specific case of the control allocation problem under input and output constraints : the goal is to limit a structural load output to an admissible level while keeping the flight behavior as close as possible to the initial one.…”