Unmanned Systems Technology 028 | ecoSUB Robotics AUVs I ECUs focus I Space vehicles insight I AMZ Driverless gotthard I InterDrone 2019 report I ATI WAM 167-BB I Video systems focus I Aerdron HL4 Herculift

25 no sensors small enough, the battery chemistries that were available couldn’t provide the energy density required and the control surfaces were too small. The idea behind it, however, was good. Over the next few years, Sloane kept an eye on the enabling technologies in the AUV market, and noted an emerging trend towards smaller AUVs. Meanwhile, market research by the NOC revealed that several suppliers, including some in the NOC with whom Planet Ocean shares facilities, were building micro- sensors that would suit even smaller AUVs, while battery technologies had made great progress. “As we started to think about it more seriously, Innovate UK and DSTL coincidentally announced a competition calling for the launch and recovery of multiple AUVs from a USV,” he says. (Innovate UK is a government body that helps British businesses to develop, de-risk and realise the potential of new ideas. DSTL is the Defence Science and Technology Laboratory, the government’s primary military r&d organisation.) “We put a consortium bid together led by ourselves and with the NOC, Southampton University and ASV – and we won. We then moved our team into the new Marine Robotics Innovation Centre at the NOC and set to work.” ASV’s role was to design the launch and recovery system, while Planet Ocean worked with the NOC to design the little AUV that would become the ecoSUBμ5. Sloane was able to do this quickly, because he had already sketched out a specification for a vehicle based on what he had learned by examining the original concept and the NOC’s market research. He stresses that the requirement for launch from an A-sized sonobuoy tube fixed many of the design criteria. “It couldn’t have any control surfaces or fins,” he says. “It could have a rudder though because that could be placed inside the cylindrical envelope.” The NOC’s team of academics and engineers worked out the hydrodynamics and the mechanical concept for the vehicle, while ecoSUB Robotics engineers worked closely alongside to help maintain focus through the two-year project and develop the electronics and software. In that iterative process they looked at various propulsion and control configurations, including a moveable duct at the back, but settled on a fixed duct containing the propeller and the rudder, and with the antenna array sticking back horizontally. The battery pack doubles as moving mass inside the body to provide pitch control. Because the batteries are positioned in the bottom half of the vehicle, they also provide natural stability in roll. BP comes onboard About six months into the project the manager of the NOC Innovation Centre discreetly advised Planet Ocean that they might benefit from letting BP know what they were doing, and also told BP that Planet Ocean was working on something that might interest the oil and gas giant, Sloane recalls. ecoSUB Robotics AUVs | Dossier Unmanned Systems Technology | October/November 2019 An ecoSUBμ5 is launched from an unmanned surface vessel built by ASV, the project that triggered the development of the smallest of the ecoSUB family (Courtesy of ecoSUB Robotics) Production-standard ecoSUBμ5s (foreground) and m5s (behind). Note the multi-frequency comms and GNSS antenna on each – horizontal on the μ5s and upright on the m5s (Courtesy of ecoSUB Robotics)