Underwater Robots - Gianluca Antonelli.pdf

4.3 Fault Detection Schemes 83
Fig. 4.2. Romeo (courtesy of M. Caccia, National Research Council-ISSIA, Italy)
The fault in athruster is also monitored in [306, 307] by the use of ahalleffect
sensor mounted on all the thrusters. The input is the desired voltage
as computed bythe controller and the TCM, the output is the voltage as
measured by the hall-effect sensor; the mismatching between the measured
and the predicted voltage isconsidered asafault. The paper also considers
fault tolerance for sensor and actuator faults and experiments, as shown in
following sections.
The vehicle Theseus [117, 118] is equipped with aFault Manager subsystem.
This provides some kind of high-level failure detection in the sense
that the mission is divided in anumber ofphases (each phase is aseries
of manoeuvres between way points); in case of failure ofaphase there is a
corresponding behavior to be activated. See Section 4.5 for detail about a
practical intervention of the Fault Manager. Ahierarchical control system
developed for future implementation onTheseus is described in[324], this is
based onthe layered control concepts [58].
References [42, 212] present anarchitecture for AUVs that integrates fault
detection capabilities of the subsystems. The hardware and software architecture,
named AUVC (Autonomous Underwater Vehicle Controller) imple-