This year the Australian Centre for Marine Robotics deployed its autonomous underwater vehicle (AUV) Sirius, equipped with a full suite of oceanographic instruments, including a high-resolution stereo camera, strobes and multibeam sonar. The AUV completed a baseline survey of the site, the data from which produced a 3D map showing the work area in detail and revealing that it’s larger than first thought. “Site mapping is the crucial first
step in any archaeological project,” Foley said, explaining that it puts the artifacts into a context that shows their spatial relationship across the wreck and seabed area to be explored. To illustrate he said that in one area of the wreck site 230 by 130 feet (70x40m) they shot more than 30,000 overlapping digital images subsequently formed into a single photomosaic in which each pixel represents less than 0.15 inch (4mm).
Te mechanism is too complex to be a one-off prototype. It had to be one link in a chain of development
“If we can come away from this
important site with a very, very good map and a much better understanding of the layout of the wreck, from that data we can begin to pose new questions to drive the research forward,” he said. The multibeam sonar identified
archaeological targets at the site and in deeper water. The researchers knew that during the original salvage operations in 1900- 01, large boulders had been dragged into deeper water to make the wreck site more accessible. One of them was raised, almost sinking the salvage ship in the process, but the effort proved worthwhile. Cleaned
up, the ‘boulder’ turned out to be a statue of Heracles, a.k.a. Hercules, now in the National Archaeological Museum in Athens. Further sonar work in 2012 confirmed the presumed locations of the relocated boulders, which for the time being remain on the ocean floor. The Exosuit put humans with
their critical faculties to work at the deep site, for the first time in a marine archaeology context. With articulating arms and legs, and thrusters, the aluminum alloy hard suit allows its occupant freedom of movement on dives to 1,000 feet (305m), extending dive time at the wreck site from minutes to hours. The one atmosphere Exosuit also rules out the decompression related injury and death suffered by some of the skilled hardhat divers who took turns sharing a single rubberized suit and brass helmet during that original recovery operation in
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