title: An Optical Fibre Depth (Pressure) Sensor for Remote Operated Vehicles in Underwater Applications.
abstract: A miniature sensor for accurate measurement of pressure (depth) with temperature compensation in the ocean environment is described. The sensor is based on an optical fibre Extrinsic Fabry-Perot interferometer (EFPI) combined with a Fibre Bragg Grating (FBG). The EFPI provides pressure measurements while the Fibre Bragg Grating (FBG) provides temperature measurements. The sensor is mechanically robust, corrosion-resistant and suitable for use in underwater applications. The combined pressure and temperature sensor system was mounted on-board a mini remotely operated underwater vehicle (ROV) in order to monitor the pressure changes at various depths. The reflected optical spectrum from the sensor was monitored online and a pressure or temperature change caused a corresponding observable shift in the received optical spectrum. The sensor exhibited excellent stability when measured over a 2 h period underwater and its performance is compared with a commercially available reference sensor also mounted on the ROV. The measurements illustrates that the EFPI/FBG sensor is more accurate for depth measurements (depth of ~0.020 m).
authors.affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Dineshbabu.Duraibabu@ul.ie.
authors.forename: Dinesh Babu
authors.initials: DB
authors.lastname: Duraibabu
authors.affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Sven.Poeggel@ul.ie.
authors.forename: Sven
authors.initials: S
authors.lastname: Poeggel
authors.affiliation: Mobile & Marine Robotics Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Edin.omerdic@ul.ie.
authors.forename: Edin
authors.initials: E
authors.lastname: Omerdic
authors.affiliation: Mobile & Marine Robotics Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Romano.Capocci@ul.ie.
authors.forename: Romano
authors.initials: R
authors.lastname: Capocci
authors.affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Elfed.Lewis@ul.ie.
authors.forename: Elfed
authors.initials: E
authors.lastname: Lewis
authors.affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Thomas.Newe@ul.ie.|Mobile & Marine Robotics Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Thomas.Newe@ul.ie.
authors.forename: Thomas
authors.initials: T
authors.lastname: Newe
authors.affiliation: Optical Fibre Sensors Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Gabriel.Leen@ul.ie.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Leen
authors.affiliation: Mobile & Marine Robotics Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Daniel.Toal@ul.ie.
authors.forename: Daniel
authors.initials: D
authors.lastname: Toal
authors.affiliation: Mobile & Marine Robotics Research Centre, University of Limerick, Limerick V94 T9PX, Ireland. Gerard.Dooly@ul.ie.
authors.forename: Gerard
authors.initials: G
authors.lastname: Dooly
keywords: Fabry-Perot; Fibre Bragg Gratings; OFPTS; Pressure; ROV; ROV control; sensors