I wonder if there is a name for garden-path sentences which emerge from mis-reading or typos; or, more interestingly perhaps, a name for a garden path candidate sentence—which is being optimistically projected during reading—forcing a misreading.
An interesting sort of confirmation bias, which it is easy to interpret as "pressure from more abstract model layers, informing the word recognition layer"...
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].
“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.
It's afaik the only glider type UUV (ed: being looked at by .mil. and production intended. and bigger than the research gliders by far.), afaik. Which is super interesting in itself, for endurance purposes. But perhaps this depth-changing mission profile is also key to its energy harvesting?
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? :)
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
I saw an Instagram Reel where someone claimed it could loiter on the seabed for extended periods powered by geothermal, but that sounds pretty fanciful to me.
This is an inaccurate take. It loiters on the bottom in an energy-efficient sleep mode.
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.
From both a defense publication article, written by the Program Manager, Kyle Woerner, and reading up on the company purportedly behind the geothermal research. They go into a bit more detail.
If I can find online links, I’ll post a follow up comment with them.
Sounds like they are using a [Buoyancy_engine](https://en.wikipedia.org/wiki/Buoyancy_engine).
The large wings are there to provide efficient forward motion when going up or down the water column.
I feel like at some point, UUVs will be able to disable one part of the nuclear triad. A submarine with nuclear warheads is such a big ticket item that no country can reasonably have a lot of them. The US has 14, Russia 11. The entire world fleet is probably in the 30s.
A UUV that can find one and follow it indefinitely could be able to neutralize it and would be, presumably, much cheaper and easier to build. How hard could it be to eventually find and track every ballistic missile submarine with them?
I’m sure there are things I’m not understanding (how communications work, whether such a sub would be able to launch ICBMs even after being torpedoed, etc.) but it seems like this should have major strategic ramifications eventually.
I think what you’re missing is that a nuclear submarine wouldn’t let a UUV “follow it indefinitely.” Also, the submarine can have its own fleet of UUVs.
Possibly. Everyone so far since the advent of nukes has generally abided by not shooting each other’s surveillance down in international territory (water, space, etc.) But perhaps that would change if UUVs are following subs.
Also I suppose the sub could re-enter its own coastal waters and then do it too, much as we shot down China’s spy balloon.
That, and also, as pointed out in e.g [1], a "boomer" submarine can launch all its SLBMs in 60-90 s. Faster than it could be torpedoed. And even if you manage to disable it very quickly, just a few launched missiles mean multiple times that number of warheads (MIRV).
Biggest issue for AUVs is how water attenuates radio, meaning this will have to surface to phone home. Guessing it will mostly be used for surveillance.
Although the US (allegedly) no longer operates them, they (and Russia and China) have used extremely low frequency communications stations spread out over miles to communicate with submerged submarines. Tensions are much lower now so submarines can take the risk of surfacing for communications checkins but I'm sure that the ELF stations could be recomissioned fairly quickly if the need arose
Given its size, it could hold a number of cheap small satellite communicators (ie garmin inreach) that could be deployed to slowly float to the surface and phone home as needed.
Yes. But these do generate lift. This is basically an underwater glider[1]. It can change it's buoyancy which would make it sink/raise straight down/up. It uses then its wings to turn this vertical speed into horizontal propulsion. It basically flies underwater in a sawtooth pattern (when seen in a side view).
This is a very energy efficient way to go the distance. These machines can loiter for months on a single charge typically. They only need to spend energy on the top and bottom points of their vertical swoops to change their buoyancy.
I always wonder how these aircraft deal with sea life and debris. The first 0 to 20 meters of sea is the most dense populated zone in the world. How do you deal with collisions? I think therefor this will never be a success.
What the huh? This has to be a joke, yeah? Those things in the sea move out of the way when things that appear threatening move through the area. Why would this be any different to that? Or to any other man made vessel in that same area. I only typed this out in case you're having a brain fart, otherwise I really feel like there should be cameras around like I'm being punk'd.
I know it's pointless pedantry and there's no reason to argue it, but aren't prototypes inherently "half-done"? If something was "fully done" it wouldn't really be a prototype anymore, but more of a gen 1.
Neither is having a prototype being assisted by external forces when demoing. :D
All in good fun and all of this is way outside of my area.
It's been exciting to see, just thought it was funny that the first images are the thing being towed.
It appears to be "giant" in the way that a small private airplane is "giant". It is larger than a sandwich but significantly smaller than all other underwater craft.
I'm guessing, but manta rays are flexible and can form vertical surfaces by how their wings flop. Or maybe they just can flop their wings different amounts to generate differing thrust for turning.
Neither is possible with todays technology. Adding a vertical control surface is a pretty easy solution though.
It is just part of the same vernacular as: UAV (Unmanned Aerial Vehicle), USV (Unmanned Surface Vehicle), and UGV (Unmanned Ground Vehicle). So UUV (Unmanned Underwater Vehicle) lines up.
Are manta rays attacking underwater vehicles now?