This paper deals with the experimental results of implementing a fault tolerant control (FTC) in a classical ball-on-plate control framework. The work builds on the fact that a robust nominal controller is found to be insufficient in accommodating a sensor fault generated by the presence of a second ball. Invariant sets are used to monitor and detect occurrence of faults in the system and a switching control strategy is implemented for accommodating the faults. With the proposed FTC implemented, experimental results confirm the fault tolerance guarantees.

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This paper considers detectability of deviation of sensors from their nominal behavior for a class of linear time-invariant discrete-time systems in the presence of bounded additive uncertainties. Detectable sensor faults using interval observers are analyzed considering two distinct approaches: invariant-sets and classical fault-sensitivity method. It can be inferred from this analysis that both approaches derive distinct formulations for minimum detectable fault magnitude, though qualitatively similar. The core difference lies in the method of construction of the invariant set offline in the former method and the reachable approximation of the convergence set using forward iterative techniques in the latter. This paper also contributes in giving a formulation for minimum fault magnitudes with invariant sets using an observer-based approach. Finally, an illustrative example is used to compare both approaches.@en

This paper deals with the design and analysis of a switching stable control reconfiguration mechanism for compensating the effects of the abnormal functioning of sensors on the closed-loop system operation. Robust positive invariance based approach is followed aiming at detecting and isolating faults in the sensors. The main objective of the paper is to guarantee the fault detection, and isolation of the faulty sensors, which are switched off from the feedback control scheme in order to use only the healthy sensors. A parametrized controller is used to ensure the stability of the closed-loop system during switching satisfying a desired performance. Simulation results are used to illustrate the efficiency of the proposed active fault tolerant control scheme in preserving switching stability.

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The paper considers the abnormal functioning of sensors (measurement channels) deployed for monitoring and control of discrete linear time invariant systems affected by additive uncertainties. The main objective is to analyze the sensor fault detectability via a robust positive invariance based technique. The analysis relies on the categorization of detectable faults and leads to certain conditions for guaranteed non-detectability, guaranteed detectability and implicit detectability.

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