Unmanned Systems Technology 027 l Hummingbird XRP l Gimbals l UAVs insight l AUVSI report part 2 l O’Neill Power Systems NorEaster l Kratos Defense ATMA l Performance Monitoring l Kongsberg Maritime Sounder

95 Kongsberg Maritime Sounder | Digest The engineering team achieves this increase by adding one or two belt-driven dynamos, which can boost the maximum output to 6 kW. That can be useful if a mission requires a heavy hoisting mechanism or winch for handling towfish or other sensors that are too large for the moonpool payload bay. For most operations, however, Kongsberg anticipates that the 4 kW generator will be enough. The Sounder’s manoeuvrability is provided by three rudders. One is placed behind the propeller, while the other two are fixed on each of the aforementioned side fins. A single steering pump is used to actuate the central rudder, and the other two rudders are mechanically linked to the middle one. That gives the Sounder a turning radius of just under 15 m when travelling at its 12 knot speed limit. Autonomy Kongsberg Maritime’s work on the K-Mate autonomy engine has continued gradually over the past four years, and development was conducted with FFI on specific software for BVLOS surface autonomy, which is now being used on the Sounder. “The vast majority of the capabilities that we see out there at the moment have some level of waypoint alignment autonomy or rudimentary survey autonomy,” Mills comments. “But we wanted to make sure we could combine survey autonomy with intelligent scene analysis and situational awareness, to put some more complex autonomous decision-making capability into USVs and so make them safe to operate over the horizon.” This surface autonomy r&d began about eight years ago, the main goal of which was autonomous decision- making aimed at compensating for gaps in the information being sent back to the operator’s control station (owing to bandwidth limitations or other issues). The K-Mate autonomy engine is intended as a flexible, modular system to come as close as possible to a ‘one-size- fits-all’ marine autopilot, and continues to be developed on other platforms. For example, the Odin USV (co- developed between Kongsberg Maritime and FFI) was used in August 2017 to demonstrate a version of K-Mate with a COLREG-compliant level of autonomous obstacle avoidance. That enabled it to navigate around stationary objects as well as crossing objects in danger of collision. The Sounder’s own collision-avoidance capability is powered by a range of sensors, the most important of which is the Simrad HALO24 radar. This provides the first layer of obstacle detection, between ranges of 20 and 40 nautical miles from the Sounder, although the resolution will degrade at the longer ranges. If the radar detects and tracks an object, several other sensors can serve to identify it. A pan-tilt-zoom camera from FLIR is integrated to provide a visual feed of anything within 3 km of the Sounder. AIS is also available for applying transponder signals to radar information, so that ships’ identifications, positions, courses and speeds can be quickly accessed. And for anything short range that passes identification by the radar, AIS and camera, a VLP-32C Lidar from Velodyne provides distance and 3D imagery of targets within a 200 m radius around the vessel. The Lidar can also be used to map or track land, with 600,000 measurements generated per second for point clouds at typical operation, and a rotation rate of between 5 and 20 Hz. “In the future we want to develop our autonomy software to handle that automatically. Ideally the radar would detect something, such as a vessel, and the camera would zoom in and identify it using machine learning if AIS doesn’t sufficiently label it first,” says Kristoffersen. “The camera and Lidar can then be used to autonomously track the direction it’s moving in, whether it’s a fishing boat or something else.” In the course of autonomously avoiding potential obstructions, however, a hydrographic survey USV could be thrown off of its course for whatever mapping or similar operation it has been tasked with. That can cause lapses in the total area covered in each survey, so Kongsberg is working to account for that in the Sounder’s autonomy. “In the future, this USV will adjust and re-attempt its survey patterns on the fly, based on how well the sonars are producing imagery at each waypoint,” Mills explains. “We’ve gone over a vast amount of data from AIS, radar, cameras and Unmanned Systems Technology | August/September 2019 The Sounder is to be equipped with various echo sounders (depending on the user), so designing the hull to prevent disruption of sensor data has been critical for the vehicle’s development