November 17, 2004
ROV Ventana carries an AUV into Monterey Canyon
In an unusual test arrangement, MBARI’s remotely operated vehicle Ventana has been carrying an autonomous underwater vehicle (AUV) during a series of recent dives in Monterey Canyon. These dives are designed to test a new multibeam sonar mounted inside the AUV. Multibeam sonar is used to create very precise depth maps of the seafloor.
By hooking the sonar up to Ventana’s power and data network, MBARI engineers can test and adjust the sonar interactively during a dive. Such interaction is not possible when the AUV is deployed alone because the AUV is programmed at the surface and the engineers have no way of communicating with it once it is underwater.
This “piggy-back” arrangement also lets researchers run the sonar within about 10 meters of the sea bottom, in order to create very detailed sea-bottom maps. The AUV alone cannot be used for such close work because it might collide with the steep canyon walls.
In addition to serving as an engineering test, these dives will provide extremely high resolution maps of one or more sites along the floor of Monterey Canyon. MBARI researchers hope to use this same ROV/AUV configuration in the future to map these same sites repeatedly, looking for signs of sediment movement. This work is part of MBARI’s Canyon Dynamics project, which aims to understand how much and how frequently sediment moves down Monterey Canyon.
Eventually this AUV will be equipped with three different instruments for mapping the seafloor: 1) A multibeam sonar, for precise depth measurements; 2) A side-scan sonar, for making visual maps of seafloor characteristics such as rock types; and 3) A sub-bottom profiler, which can show layers of sediment and rock up to several hundred meters below the seafloor.
For additional information or images relating to this article, please contact: Kim Fulton-Bennett