Autonomous Underwater Vehicle
Australian Autonomous Underwater Vehicle (AUV) Facility
Autonomous Underwater Vehicles (AUVs) are becoming significant contributors to modern oceanography, increasingly playing a role as a complement to traditional survey methods. While very large-scale surface processes can be addressed adequately by remote sensing and ship-borne systems, characterisation of many marine processes requires the ability to sense at high resolutions in close proximity to the seafloor. The ability to conduct geo-referenced, high resolution, repeatable surveys of marine habitats – particularly those beyond diver depths – represents one of the key contributions of recent advances in AUV systems.
The objectives of the IMOS AUV Facility are to provide access and operational support for AUV systems for the marine science community in Australia. The Facility currently operates an AUV designed for high-resolution seafloor imaging. This vehicle is available to support marine research based on a call for proposals. The next round of proposals are due Oct 30th, 2009.
- The AUV Sirius being retrieved aboard the R/V Challenger offshore of the Tasman Peninsula, Tasmania
The AUV Sirius is designed for undertaking high resolution benthic optical and acoustic imaging work. This experimental platform is a modified version of a mid-size (200 kg) robotic vehicle called SeaBED built at the Woods Hole Oceanographic Institution. Its maximum operating depth is 700 m. The submersible is equipped with high resolution stereo cameras and strobes, a 330 kHz multibeam sonar, a 1200 kHz Doppler Velocity Log (DVL) capable of collecting water-column velocities in addition to vehicle velocity over ground, a depth sensor, a fluorometer that measures CDOM, chlorophyll-a and backscatter, and a conductivity/temperature sensor. A variety of additional navigation sensors, including GPS, and Ultra Short Baseline (USBL) acousting positioning, enable precise tracking of the vehicle allowing survey data to be geo-referenced at high precision. All data is time-stamped and logged on-board the vehicle during operation.
Data collected by the AUV consists of stereo imagery, multibeam sonar, vehicle navigation and water chemistry data. All data products are precisely geo-referenced using state-of-the-art terrain-aided navigation algorithms. Optical imagery is delivered as individual high-resolution, color-corrected images (geotiffs) and also in processed form, as mosaics and 3D sea floor reconstructions.
- Forty image, 10 m long mosaic of sponge beds in 80 m deep water from Ningaloo marine park, Western Australia
- Approximately 20 m long section of a three-dimensional sea floor reconstruction of fringing reef from the Tasman Penninsula, Tasmania. This reconstruction includes photographs from two passes over the same object. The excellent correspondence highlights the value of precise navigation.
Optical imagery derived from the AUV has been used primarily to document benthic habitats, particularly beyond diver depths. Precise geo-referencing of the data products enables data derived from the AUV to complement and enhance the value of data derived from other assets, e.g., ship-board multibeam. The AUV has been deployed in collaboration with scientists from a variety of Australian and international institutions at various sites around Australia:
- AIMS: Benthic habitat assessment beyond diver depths, Ningaloo Reef, WA
- University of Sydney, James Cook University, CSIRO, Oxford, University of Edinburgh: Documentating drowned shelf-edge reefs at multiple sites along the Great Barrier Reef with application to predicting the response of modern reef systems to climate change, Great Barrier Reef, Qld
- DEH SA: Benthic habitat documentation in support of potential declaration as a marine park, Sir Joseph Banks Island Group, SA
- Marine Biological Labs (Woods Hole, MA, USA), National Geographic: Non-disruptive photo-documentation of cuttlefish nocturnal camouflage, Whyalla, SA
- TAFI: Biological assemblage characterisation of rocky reef systems in deep shelf waters beyond diver depths in support of physical surrogate development for remote (acoustic) biodiversity mapping, Tasman Peninsula and Huon MPA, TAS