Fault-tolerant control allocation with actuator dynamics: Finite-time control reconfiguration

Cristofaro, Andrea; Johansen, Tor Arne

doi:10.1109/cdc.2014.7040165

Cited by 9 publications

(4 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Besides the mere validation of the theoretical results, it might be interesting to the test the proposed approach in a more practical scenario. While modeling errors can be treated in a natural way by incorporating them in the nonlinear uncertainty (⋅, ⋅, ⋅), the presence of noisy measurements provides additional challenges [11][12][13][14]. To this end, the robustness of the method with respect to noise has been successfully tested by injecting a zero-mean random signal in the system, and the corresponding isolation residuals are reported in Figs 12-15, which show the effectiveness of the scheme.…”

Section: A Simulation Studymentioning

confidence: 99%

“…While this fact does not compromise the fault detection and isolation procedures, it constitutes an additional challenge towards addressing control reconfiguration. A possible solution to this problem has been proposed in , consisting in two main steps: estimation of the faulty actuators steady‐state (if any) using residuals and finite‐time control reconfiguration , i.e. determination of a reduced‐order actuator input

\overset{v}{true} (t)

able to guarantee convergence in a finite time τ ⋆ >0 of the safe actuator states to the desired control input

\lim_{t \to τ^{⋆}} | \tilde{G} ũ (t) - {\tilde{τ}}_{c} (t) | = 0,

where

{\overset{τ}{true}}_{c} (t) = τ_{c} (t) - G_{i_{♯}} u_{i_{♯}}^{♭}, u_{i_{♯}}^{♭}

being the estimate of the faulty actuator steady‐state.…”

Section: Control Reconfigurationmentioning

confidence: 99%

“…Then the resulting estimation error (s) ∶= x − z (s) , with z (s) assigned by (12), is decoupled from the linear part of faults of the typēs(x, u).…”

Section: Fault Isolationmentioning

confidence: 99%

“…Once the fault has been detected, four isolation observers have been implemented: as rank G(x) = 2 ∀x, no actuator clusters have been taken into account. The observers have been designed according to (12), with matrices F i = diag(−3, −5, −7) ∀i = 1, .., 4 and by tuning the tolerance parameter = 0.6. The norm of residuals, together with an overall isolation threshold, is depicted in Figs 4-7: the reset of residuals to the zero level, corresponding to re-inizialize the observer when |Bx| = , is clearly visible.…”

Section: A Simulation Studymentioning

confidence: 99%

See 3 more Smart Citations

Fault‐Tolerant Control Allocation for Overactuated Nonlinear Systems

Cristofaro

Polycarpou

Johansen

2017

Asian Journal of Control

Self Cite

View full text Add to dashboard Cite

This paper addresses the problem of fault‐tolerant control allocation for input affine nonlinear systems. The proposed scheme is divided in three main tasks: fault detection and estimation using a nonlinear observer, fault isolation through a bank of unknown input observers with a resetting policy to reduce the effects of nonlinearities and control reconfiguration based on reduced order allocation. Analytical results regarding the isolability and reconfigurability of actuator faults are derived and a simulation example is used to illustrate the the proposed fault tolerant control methodology.

show abstract

Section: A Simulation Studymentioning

confidence: 99%

\overset{v}{true} (t)

able to guarantee convergence in a finite time τ ⋆ >0 of the safe actuator states to the desired control input

\lim_{t \to τ^{⋆}} | \tilde{G} ũ (t) - {\tilde{τ}}_{c} (t) | = 0,

where

{\overset{τ}{true}}_{c} (t) = τ_{c} (t) - G_{i_{♯}} u_{i_{♯}}^{♭}, u_{i_{♯}}^{♭}

being the estimate of the faulty actuator steady‐state.…”

Section: Control Reconfigurationmentioning

confidence: 99%

“…Then the resulting estimation error (s) ∶= x − z (s) , with z (s) assigned by (12), is decoupled from the linear part of faults of the typēs(x, u).…”

Section: Fault Isolationmentioning

confidence: 99%

Section: A Simulation Studymentioning

confidence: 99%

See 2 more Smart Citations

Fault‐Tolerant Control Allocation for Overactuated Nonlinear Systems

Cristofaro

Polycarpou

Johansen

2017

Asian Journal of Control

Self Cite

View full text Add to dashboard Cite

show abstract

A nonlinear fault-tolerant thruster allocation architecture for underwater remotely operated vehicles

Corradini

Cristofaro

2016

IFAC-PapersOnLine

View full text Add to dashboard Cite

This paper proposes an actuator failure tolerant robust control scheme for underwater Remotely Operated Vehicles (ROVs). A reduced order observer has been introduced for estimating the ROV velocities and a sliding mode control law has been developed using the available position measurements and the velocity estimates provided by the observer to achieve output regulation. A thruster failure is shown to be detectable simply checking the presence of any deviation of the observed sliding surfaces. Moreover, an isolation policy for the failed thruster is proposed. Finally, control reconfiguration is performed exploiting the inherent redundancy of actuators with the implementation of an adaptive input allocation architecture. An extensive simulation study has been performed, supporting the effectiveness of the proposed approach. © 201

show abstract