Next Article in Journal
Modelling a Propeller Using Force and Mass Rate Density Fields
Next Article in Special Issue
A Novel Gesture-Based Language for Underwater Human–Robot Interaction
Previous Article in Journal
Deployment and Maintenance of Wave Energy Converters at the Lysekil Research Site: A Comparative Study on the Use of Divers and Remotely-Operated Vehicles
Article Menu
Issue 2 (June) cover image

Export Article

Open AccessArticle
J. Mar. Sci. Eng. 2018, 6(2), 40; https://doi.org/10.3390/jmse6020040

Fault-Tolerant Control for ROVs Using Control Reallocation and Power Isolation

CRIS—Centre for Robotics & Intelligent Systems, University of Limerick, Castletroy, Limerick V94 T9PX, Ireland
*
Author to whom correspondence should be addressed.
Received: 7 March 2018 / Revised: 4 April 2018 / Accepted: 10 April 2018 / Published: 12 April 2018
(This article belongs to the Special Issue Intelligent Marine Robotics Modelling, Simulation and Applications)

Abstract

This paper describes a novel thruster fault-tolerant control system (FTC) for open-frame remotely operated vehicles (ROVs). The proposed FTC consists of two subsystems: a model-free thruster fault detection and isolation subsystem (FDI) and a fault accommodation subsystem (FA). The FDI subsystem employs fault detection units (FDUs), associated with each thruster, to monitor their state. The robust, reliable and adaptive FDUs use a model-free pattern recognition neural network (PRNN) to detect internal and external faulty states of the thrusters in real time. The FA subsystem combines information provided by the FDI subsystem with predefined, user-configurable actions to accommodate partial and total faults and to perform an appropriate control reallocation. Software-level actions include penalisation of faulty thrusters in solution of control allocation problem and reallocation of control energy among the operable thrusters. Hardware-level actions include power isolation of faulty thrusters (total faults only) such that the entire ROV power system is not compromised. The proposed FTC system is implemented as a LabVIEW virtual instrument (VI) and evaluated in virtual (simulated) and real-world environments. The proposed FTC module can be used for open frame ROVs with up to 12 thrusters: eight horizontal thrusters configured in two horizontal layers of four thrusters each, and four vertical thrusters configured in one vertical layer. Results from both environments show that the ROV control system, enhanced with the FDI and FA subsystems, is capable of maintaining full 6 DOF control of the ROV in the presence of up to 6 simultaneous total faults in the thrusters. With the FDI and FA subsystems in place the control energy distribution of the healthy thrusters is optimised so that the ROV can still operate in difficult conditions under fault scenarios. View Full-Text
Keywords: fault-tolerant control; thruster fault; fault detection and isolation; fault accommodation; ROV; remotely operated vehicle; underwater vehicle fault-tolerant control; thruster fault; fault detection and isolation; fault accommodation; ROV; remotely operated vehicle; underwater vehicle
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Capocci, R.; Omerdic, E.; Dooly, G.; Toal, D. Fault-Tolerant Control for ROVs Using Control Reallocation and Power Isolation. J. Mar. Sci. Eng. 2018, 6, 40.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
J. Mar. Sci. Eng. EISSN 2077-1312 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top