Valeport’s SWiFT profiler range is supporting USV manufacturers to get the data they require and to realise their ability to reduce the cost of ocean mapping and reach the most remote areas of the ocean.
The manufacturer of wind and solar-powered autonomous surface vehicles, Saildrone, has integrated Valeport’s most popular sound velocity profiler, the SWiFT SVP, into a mission to test the accuracy and longevity of a Saildrone platform for shallow-water multibeam bathymetry.
The mission developed in partnership with the University of Southern Mississippi (USM) and the National Oceanic and Atmospheric Administration (NOAA) took place during September 2019. Two Saildrone USVs were deployed off the coast of San Francisco using solar energy to power a suite of onboard survey-grade sensors to collect a variety of in-situ meteorological and oceanographic measurements.
The first USV, SD 1024, known as the “Surveyor,” was equipped with a shallow-water multibeam echo sounder. The echo sounder bounces 512 pings of sound 20 times per second off the ocean floor, adjusted for heel and roll. Saildrone recognising the accuracy of the data gathered would be significantly reduced without a sound velocity profile, developed an autonomous winch system, to lower Valeport’s SWiFT sound velocity profiler through the water column to directly measure sound velocity every half meter. Saildrone’s second USV, SD 1025, known as the “Profiler,” was equipped with the autonomous winch for sound velocity profiling using Valeport’s SWiFT SVP.
Working collaboratively, the two saildrones successfully mapped a coastal area, performing multiple sound velocity profile casts over a three-day period, with the deepest cast reaching a depth of 85 meters (280 feet). This approach allowed for maximum efficiency: one vehicle surveying non-stop 24/7 while the other took regular sound velocity profiles. All of the data was uploaded and available to download from Saildrone’s servers within five minutes of each cast completion.
Saildrone says its mapping USVs will be able to provide International Hydrographic Organisation (IHO)-standard shallow-water bathymetry anywhere in the world, no matter how remote the area might be. They will be able to deliver information that is critical for marine safety in areas previously uncharted, or after major disasters such as earthquakes, tsunamis, or hurricanes, which can significantly alter the seabed or create dangerous underwater obstacles.
Mapping the entire ocean floor is the aim of the SeaBed 2030 project, a UN-backed joint initiative between GEBCO (General Bathymetric Chart of the Oceans) and the Nippon Foundation to map the world’s ocean floor by 2030. The oceans make up more than 70% of the earth’s surface and yet we know more about the topography of Mars and several other planets than the ocean floor. Scientists recently confirmed that less than 20% of the ocean floor has been mapped in a meaningful and accurate way. It is estimated that to map the ocean floor using traditional ship-based mapping operations would take up to 350 ship-years to generate a complete map of the deep ocean at a cost of $3 billion. The ability to map the ocean floor with autonomous technologies will play a key role in facilitating the Seabed 2030 vision, not only in significantly reducing the cost of ocean mapping at scale but more easily and efficiently reaching the most remote corners of the ocean. Saildrone proposes 20 vehicles equipped with multibeam echo sounders would meet the Seabed 2030 deadline.