achieve the same bathymetric output. Because systems based on interferometric technology create an order of magnitude of more data points per ping than an MBES, the processing has always been more involved. Both MBES and interferometric sonars generate multiple simultaneous beams and measure echo-return times, while the latter also measure phase differences between the beams, requiring more sophisticated algorithms. Dowdeswell says that using AI has dramatically lowered this hurdle, so data can now be processed in real time on the vessel. “What we’re looking for is continuous structures; the seabed is a continuous structure – mooring lines in the water and harbour walls are continuous. So, it examines all the data, looking for pockets of data that are connected to other pockets that would then create features, and there is some reinforcement learning in there,” he says. “The first ones have been tweaked to make them better and we’re constantly asking for customer feedback. If they’ve got a data set that isn’t doing as well as they hoped it would, we invite them to send it to us so we can – maybe – improve the model.” In one early application of the technology, GeoAcoustics is cooperating with hydrogen-powered USV developer ACUA Ocean and Unmanned Survey Solutions on a ninemonth Innovate UK project to find and map environmentally important seagrass beds off the coast. “The plan is to use the GeoSwath to look for the seagrass, and there’s a large proportion of AI embedded in that to look at the data. Here, we’re not only looking at the bathymetry, but also at the intensity of side-scan sonar returns to try to determine the presence or absence of seagrass,” Dowdeswell explains. When that mission is complete, he intends to turn his team’s attention to applying AI to the company’s subbottom profiling sonar, which is used to find discontinuities in the seabed, including layers of sediment of varying density, and buried objects such as pipelines and wrecks. One data-processing challenge lies in identifying and eliminating unwanted reflections that reverberate multiple times between the seabed and the sonar towfish and give the false impression of real strata. A second and more complex problem is detecting structures in sub-bottom data. “I think that will probably need more of a supervised approach; training it based on lots of data examples that have been analysed and labelled by geophysicists,” says Dowdeswell. By combining advanced AI for vessel control and processing sensor data, he believes it should be possible to automate the whole survey process. “Having launched the vessel, the operator can rely on it to undertake adaptive survey line planning, based on real-time feedback of the coverage area, enabling the survey to be conducted more efficiently and providing confidence that the survey coverage meets requirements,” he says. Bringing AI into sensors for uncrewed systems is the project that has given Dowdeswell the most satisfaction. Despite the complexity of the technology, his philosophy of engineering favours simplicity wherever it is practical. “We try to keep the solution as simple as possible, and make sure that what we are designing and making is what the end-users actually want,” he says. 23 Uncrewed Systems Technology | June/July 2024 Born in 1970, Dr Richard Dowdeswell is chief commercial officer and co-owner of GeoAcoustics, where he leads a team of 23 people in design, manufacturing and product support, working alongside his wife, Linda, who is general manager. At school, his favourite subjects were physics and chemistry, while geology and rock collecting were his main hobbies. “I had understanding parents, who would humour me with trips to abandoned mines to pick over the spoil tips, looking for new specimens, some of which are still in my collection,” he says. At Leeds University, Dowdeswell turned his enthusiasm into a bachelor’s degree in mineral engineering, which he followed with a PhD in instrumentation and management from Cranfield University. Later came a BSc from the Open University, combining oceanography, database design, Visual Basic application development, cosmology and astronomy, followed by a master’s in commercial law from Northumbria University. His first job was as a research associate at the University of Manchester (UMIST) working on novel instrumentation systems. In 1999, he founded the Keiku Group as a spin-off to commercialise water-quality instruments for the brewing industry. A decade at the UK’s Centre for Environment, Fisheries and Aquaculture Science followed, ending in 2017, when Dowdeswell was headhunted to run Kongsberg GeoAcoustics, which he took to independence as GeoAcoustics in December 2020. Dr Richard Dowdeswell
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