62 In operation | Seasats Lightfish USV risk factors. The ocean always has a say, but we’re quite happy with this revision.” Such design changes have now been made across all Lightfish units. As with the first attempt, the current one is being made with a stock Lightfish USV using no special enhancements or integrations to ensure a successful crossing is possible with any of the units leaving the factory. The USV launched from Dana Landing in San Diego using a boat ramp that Seasats has used many times for tests. A launch cradle has been built in-house around a dolly designed to house individual finished Lightfish units. For launching both tests and commercial operations, Seasats rolls one of these cradles out of its workshop and into a van before driving it to the designated ramp for deployment, where the cradle is walked into the water and the USV is decoupled from the dolly to slide away by itself. Rather than supply a physical checklist of manual tests or inspections required before deployment, the user interface (UI) contains a pre-launch checklist detailing 10-12 items, such as ensuring the hatch is secured, the backup tracker is working, the cellular radio is sending and receiving normally, and so on. Automated checks are always running in the background, as is a dedicated error display window for indicating any potential causes of concern, with the UI functioning via the web browser on any computer, tablet or phone for ease of access and mission monitoring. An audit log window provides a timeline of subsystem tests, checks, commands and other actions performed by monitoring and operations staff. View from the bay The Seasats team can monitor the USV’s progress from its facility in San Diego, or from any device that can log into the web portal for its GCS software or UI (the public UI can be viewed freely at track.seasats.com). Rodriguez developed the majority of the UI’s initial architecture, with a particular focus on keeping its layout and functions as simple and user-friendly as possible, such that any non-engineering personnel could use it. “Because Lightfish is a solar boat, planning out the route was a lot like planning routes for a sailboat race. There are different aspects, different things across different aspects of the ocean that you want to avoid, and others you want to take advantage of,” Kramers says. “On our first trip from San Diego to Hawaii, we just drew a straight line and stuck to it to demonstrate that our vessels can do that. Our customers can always keep it simple and do that too, but this time we wanted to optimise more, so we checked weather patterns because cloud cover is something you want to avoid, and it being winter in the northern hemisphere at the moment, directed the route further south than we did last time. “The benefit is that we get more energy extracted via solar per day and, yes, we travel a fair bit longer distance-wise, but it still makes the trip significantly faster.” Not long after deployment from San Diego, the USV quickly turned south before taking a south-westward curving trajectory towards Hawaii. It successfully crossed through Waikiki in Hawaii during the week starting March 3, some slight acceleration orders having been sent to the USV so that it could take part in a US Naval event there. After departing the archipelago, the vessel will follow a route engaging in a westerly line towards Guam (to showcase the boat for US Navy personnel there, as it did in Waikiki), following which it will turn northwards in the direction of Japan. The waypoints were plotted manually, although Seasats may in future engineer AI-powered means for automating survey route plotting in the event that further ease of use could be achieved. Balance of power In addition to viewing and adjusting the route where necessary through an on-screen map of the Pacific, the company scrutinises all possible health and performance parameters of the Lightfish as it travels. Of these, the most critical is a plethora of power sensors that track power telemetry for every subsystem. A detail-dense analytics screen that Rodriguez shares with us displays a pie chart of average power consumption for every onboard electrical or electronic device, as well as power generated by the solar and generator systems. In total, 24 slices of the pie were shown, including low-voltage devices such as an Ethernet switch and a USB hub; naturally, the two power-generation systems occupied slightly more than 50% of the circle. April/May 2025 | Uncrewed Systems Technology The USV has deliberately been designed and built as small and lightweight, such that no special equipment is needed to transport and deploy it
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