GPA Seabots SB 100 | In operation regular cleaning because nowadays, port owners really want to create biodiversity inside their waters, and understanding water quality is key to predicting whether marine life will flourish in a harbour,” Barchino says. “So as well as doing hydrographic surveys by integrating echo sounders and sidescan sonars, we’ve also integrated things like 2 litre electrically powered water samplers and underwater cameras, to directly inspect the biodiversity and the parameters of the water that can influence that.” On top of these, other payloads including sound velocity profilers, subbottom profilers and water quality measurement tools have been integrated, often on the basis of each harbour authority having its own inventory of familiar survey devices it prefers to keep using with its Seabots. To enable that, payload sensors are flexibly integrated via the Black Box, GPA Seabots’ proprietary central control unit. This features a range of USB, Ethernet, and serial (including RS-232 and RS422) ports for communicating with different electronics, as well as 5, 12 and 24 V ports for power distribution from a central transformer. “If there’s a new sensor someone wants us to integrate with a new connector, we can easily modify the Black Box to accept that,” Barchino adds. “Other USV manufacturers’ main computers are often closed systems locked into specific payloads, but we’ve found that keeping our system open and flexible to new payload integrations is indispensable for our harbour clients.” Inside the Black Box is a 10thgeneration Intel i7 CPU with 32 Gbytes of RAM running on Windows 10. The enclosure is ruggedised and sealed to prevent salt water ingress, while the top of the Black Box integrates a cooling fan for blowing air into the housing’s dorsal heat sink. Although the controller unit can be customised, GPA Seabots does not offer versions without this fan. Given the heat in the Mediterranean and elsewhere, such as the Middle East, failing to cool the USVs’ computers against an ambient heat of up to 50 oC and the additional heat produced by the PC would result in the system shutting down. All the USVs are optimised for moving at 1 m/s (3.6 kph), an ideal speed for gathering waste and data without producing wave wakes that would spread trash and oil around, or splashing that would interfere with data integrity. That speed is achieved through dual Blue Robotics T200 electric thrusters, which Barchino says are a vital component for saving on part and assembly costs, as they are a mass-produced, turnkey solution for uncrewed aquatic vehicles. Oil, battery and solar power Each absorber on the Cleaner has a maximum capacity of 6 litres of oil, with an actual recommended capacity of 4 litres, and can be used just once or twice before having to be disposed of in a special container. Each USV can therefore be sent to capture up to 12 litres of spills at a time before needing to return to its operator for maintenance. The litter basket meanwhile can carry up to 30 litres of refuse, but as litter will not compress together neatly, both the Cleaner and Harbot integrate a weight sensor to detect when the basket is reaching capacity. Although units sold and hours worked by the Cleaner far outstrip those of the Harbot, the Harbot and its operating concept deviate most from the Cleaner when it comes to post-operational maintenance. For instance, while the Cleaner needs to undergo a battery swap or plug-in recharging to replenish its energy store, the Harbot has solar cells on top of its domeshaped roof to recharge while stationary. Ideally, each Harbot would spend one or more days sitting still and 59 Uncrewed Systems Technology | December/January 2024 The Harbot prototype features a larger waste collection aperture than the Cleaner
RkJQdWJsaXNoZXIy MjI2Mzk4