Uncrewed Systems Technology 047 l Aergility ATLIS l AI focus l Clevon 1 UGV l Geospatial insight l Intergeo 2022 report l AUSA 2022 report I Infinity fuel cell l BeeX A.IKANBILIS l Propellers focus I Phoenix Wings Orca

64 Insight | Geospatial surveys to 2.5 potentially secchi depths [a unit measurement of water clarity].” “You could of course use sonar, but if you incorrectly assume a certain water shallowness you risk hitting something like a rock and damaging or losing that expensive payload, or even the vehicle itself.” The VQ-840-GL is optimised for use in river flow studies, ecological surveys, fishery management and other environmental surveys. Notably, UAVs designed and equipped for bathymetry can provide the opportunity to collect topographic, bathymetric and water surface-level data simultaneously. That can be vital for organisations looking to make digital twins of assets that extend above as well as below the water, such as harbours, oil rigs and wind farms. 3D sonar-based modelling is highly valuable to such groups, but including sonar data in topo-bathymetric surveys can be challenging, as any UAV equipped with a sonar would have to dip it into the water to use it correctly, and hence risk crashing. To avoid this issue and enable straightforward sonar mapping for geospatial customers, Switzerland- based Topodrone A has developed the Aquamapper, a kind of towfish that is pulled through the water by an UAV. It weighs 2.5 kg, and hangs beneath the end-user’s UAV platform by a tether. Inside is a single-beam echo sounder that pulses at 450 kHz, operating at an immersion depth of 0.2-0.4 m. “Deploying and recovering USVs and UUVs can be rendered hazardous by features like rocky beaches or wildlife, but with our system a UAV and Aquamapper can fly to lakes, reservoirs, and coasts from a safe launch spot some distance away,” says Mayksim Baklykov, Topodrone’s CEO. “It can measure 100 m down into the water, and work at speeds of up to 12 kph through it. We plan to unveil different Aquamappers in the future too, which will integrate different kinds of echo sounders, such as dual-beam and multi-beam systems.” A GNSS-INS with GPS, GLONASS, Galileo and BeiDou support is integrated, as is PPK compatibility for enhanced accuracy of georeferencing. One notable use case so far was by Graphein Topo in Romania, which conducted 14 flights with a DJI Matrice 300 integrating the Aquamapper and Topodrone’s Lidar Ultra payload. Over these flights it carried out laser scans of forest terrain about 32 km long by 400 m wide, as well as performing bathymetric surveys of six river crossing areas. Summary Geospatial surveys are now performed autonomously over a wide variety of industries, and depend on a great range of technologies (for more vehicles and technologies for geospatial missions, see our Intergeo 2022 report, page 66). It is worth noting that uncrewed aircraft and watercraft, as well as ground vehicles in some cases, have eclipsed not only crewed vehicles in geospatial photography and mapping but also satellite imaging systems. While the latter was once a prized tool of choice for mapping the Earth, the former’s closer proximity to areas of geospatial interest – not to mention the advances in their sensor technologies – enable them to create sub-millimetre accurate 3D models with far higher detail. However, given the much wider fields of view that satellites and HALE pseudo- satellite UAVs can achieve compared with autonomous vehicles operating closer to the Earth, further advances in camera and Lidar technologies could one day enable them to carry out persistent high-resolution mapping of thousands of square kilometres per vehicle per day. The future of geospatial mapping might therefore include a return of satellite systems. December/January 2023 | Uncrewed Systems Technology Topodrone’s Aquamapper towfish can be flown into the water from a safe distance, where hand-launching a USV or UUV would be dangerous for crews (Courtesy of Topodrone)