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81 Roboat | In operation Post-operation charging As mentioned, after about 8 hours of operation, the Roboat will need to recharge its battery. Using a lithium battery (over a lead-acid or similar chemistry pack) was a key decision, to enable the high recharge speeds needed to minimise the Roboat’s downtime. The self-charging architecture of the Roboat might evolve in different ways, depending largely on the preferences of the Amsterdam city authorities. Although the city aims to eliminate all ICE-powered canal craft by 2025, the waterside charging infrastructure is not yet fully established. “Despite there now being a great many electric boats in the canals, there aren’t that many chargers, but in any case we’re researching different methods of wireless inductive charging,” Deinema says. “Most likely we will implement this by installing one charging coil in the quay wall and another in the boat, so that when they come into close proximity, a charging current will run between them.” Charging wirelessly would avoid the need to plug in a charging connector, as that would require plugging in a robotic arm amid the motion of the water, fluctuations in water level and water motion produced by other boats. Deinema comments that AMS Institute plans to experiment before 2021 with a wireless charging coil (supplied by Wiferion) installed in a floating dock, which would naturally follow the movement of the water as the Roboat would, to examine its efficiency and any variations in charging. Future developments “Going forward, the ambition is to set up a pilot programme in 2021 for early adopters, focusing on one of the specific use-cases for Roboat. We’re leaning heavily towards waste collection in that respect,” Deinema says. As mentioned, AMS Institute and MIT anticipate a range of other uses for the Roboat. Pending special dispensations being granted for faster travel on water, the researchers have envisioned using a small group of similar USVs to ferry people from one waterfront to another during major events. Dubbed the ‘roundAround’ system, the Roboats would operate in a circle, picking up passengers on one side and dropping them off at the other, while autonomously ‘opening’ the circle to let other boats through, thereby avoiding congestion in the waterway. The boat’s potential for convenient transport is being closely considered for the ‘roundAround’ system and other modes of implementation, with the aforementioned smartphone app potentially being repurposed as a canal- based ride-hailing system. With all these different purposes, a number of inlays for the hull are being constructed. These would enable a dumpster inlay to be installed for more secure refuse carrying; and outside of waste collection hours, this could be lifted out and a seating arrangement inlay installed instead, with or without roofing. Unmanned Systems Technology | April/May 2020 (For full-scale Roboat) Roboat USV Dimensions: 4 x 2 m Hull: aluminium Maximum operating weight: 2000 kg Operating speed: 6 kph Payload capacity: 1000 kg Power: 12 kWh lithium- polymer battery Some key suppliers Operating system: ROS Main thrusters: Torqeedo Additional thrusters: Vetus Batteries: Murata Wireless charging: Wiferion Lidar: undisclosed IMU: Lord Microstrain RTK-GNSS: Emlid Shipyard: Stormer Marine Specifications The researchers also intend to develop autonomous water taxis using the Roboat