I was wondering how this UUV was powered and all that DARPA was willing to divulge was "Novel energy management techniques" and "undersea energy harvesting" [1].
Anyone have any insights?
Anyone have any insights?
https://www.defenseone.com/technology/2024/05/giant-military...
“One thing that you notice in underwater vehicle design is you typically can have either a vehicle that lasts very long periods of time but can't really carry anything with it,” Woerner said on a podcast in 2022. “But if you want something that can carry a sensor or payload that is perhaps a larger size or mass, or has a larger energy draw, you tend to need a more traditional underwater vehicle, propeller driven in most cases. And those tend to not have anywhere near the endurance” that the military is looking for.
The ocean itself is full of potential sources of energy, such as currents, waves, and even subtle differences in water temperature or salt levels. But there’s no single perfect source of ocean energy for what DARPA is trying to accomplish.
“If you're interested in maybe closer to surface transport, wave energy is a really great resource, most of the wave energy is distributed near the surface. If you want to go into deeper water, right? That means that wave energy wouldn't be a great resource for that,” Sandia National Laboratory engineer Kelley Ruehl, an advisor on the program, said on the podcast. Similarly, current energy is a very localized resource, where we have tidal streets— those are unique locations in the world. So it's a very specific place that one would need to harvest tidal-energy resource.”
DARPA said PacMar Technologies, another contractor on the Manta Ray program, will spend the rest of this year testing a full-scale energy-harvesting system.
Just guessing here, but... it's sinking and rising. Well, perhaps it can take some mass of water onboard & run temperature differential energy harvesting off that. Take on warm surface water, slowly glide down 1000 ft (while going much further forward), then run a thermo-electric generator against the cold deep. Swap water & take 300 gallons of cold water, glide up 1000 ft (and forward), then run a thermoelectric generator against the warmer surface water or the air and/or solar. Repeat ad-infinitum. No idea what kind of power you could pull here but maybe, and it fits with the glider core concept.
And yeah, maybe if you do find an underwater vent you can supercharge? :)
Shout out to The War Zone (TWZ)'s coverage over time. The recent is decent but links their previous which looked about some. https://www.twz.com/news-features/manta-ray-underwater-drone...
TWZ talk about something mentioned elsewhere in the comments, yes, the data-linking challenges are partly tackled by having a "data bubble" that can float to the surface & uplink, who knows, maybe downlink relay too (unspecified). I definitely want to imagine the data bubble as a recursive system, as itself a smaller glider drone, but I'm 100% making that up, is my sci-fi impulse.
Essentially you use a fluid which freezes at the bottom of the ocean and loses volume (some kind of paraffin)
And then you hook it up with some actuated valves and N2 accumulators so the volume change and energy harvesting happens "out of phase" - at the surface, you can deflate an external bladder and sink, and at the bottom, you use some stored energy to reinflate the bladder
With a large enough volume you get near infinite range, only have to pay for payload and any onboard electronics
this report has some more info on the absurd efficiency of thermal gliders: https://escholarship.org/content/qt1c28t6bb/qt1c28t6bb_noSpl...
So you build a sperm whale UUV.
Separately, it collects small amounts of energy via geothermal means similar to something like regenerative braking. This, of course, allows it to sleep for longer periods.
If I can find online links, I’ll post a follow up comment with them.
0: https://www.eurogamer.net/war-thunder-players-leak-military-...
Similar idea to those weather balloons we were talking about last year ?
Is that even possible in the ocean ?