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The mapping AUV maps the bottom by emitting sound at various frequencies that reflect off the bottom and return to receivers on the vehicle. The amount of time the sound takes to return and the energy with which it is returned are processed to make "images" of the shape and hardness of the bottom can be made. The vehicle is programmed to "mow the lawn" to fully cover a region of interest over a deployment.
The vehicle has three mapping sonar systems aboard
Multibeam sonarReson 7100 200 kHz multibeam sonar generates bathymetry data at 1m lateral resolution in autonomous surveys flying at 60-90m altitude, and 0.5m resolution when mounted to an ROV flying at 20m altitude. The vertical precision is 0.30m (limited by pressure sensor). The bathymetry beam footprints are as small as 0.5m across. The bathymetry grid at right has a lateral resolution of 1m. |
 This three dimensional view of the Monterey Canyon channel was made from multibeam bathymetry data collected with the mapping AUV. It was generated using 6,770,883 soundings. Ripples and erosion channels are visible in the canyon axis. Image: David Caress © 2005 MBARI |
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Sidescan sonarEdgetech 110 and 410 kHz chirp sidescan sonars image the seafloor character and fine-scale features at ~10 cm resolution. |
 Larger version |
This map was generated from sidescan data collected in Monterey Canyon. Dark patches are areas of low reflectivity. Image © MBARI 2006 |
Subbottom profilerEdgetech 2-15 kHz chirp subbottom profiler images subsurface sediment structure. It achieves up to 50m penetration with 10 cm vertical resolution. |
 This image was created with the AUV's subbottom profiling sonar. It shows layers of sediments draping the walls of the inner Monterey Canyon. Image: David Caress © 2005 MBARI |
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>> More about the data processing
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