Fault detection and accommodation for roys

A new approach for fault detection and accommodation for remotely operated underwater vehicles is proposed in this paper. The proposed Fault Detection and Accommodation System (FDAS) consists of two subsystems: Fault Detection Subsystem (FDS) and Fault Accommodation Subsystem (FAS). The FDS uses fault detector units (FDU), associated with each thruster, to monitor their healthy state. Robust and reliable fault detection units are based on integration of self-organising maps and fuzzy logic clustering methods. These units are able to detect internal and external faulty states of a thruster. The FAS uses information provided by the FDS to accommodate faults and perform an appropriate reconfiguration. A control energy cost function is used as the optimisation criteria. In fault-free and faulty cases the FAS finds the optimal solution, which minimise this criteria. The proposed FDS is evaluated with data obtained during test trials.