Stealthy Drone Can Hide Underwater For Months, Then Float To Surface To Take-Off (digitaltrends.com)

An anonymous reader writes from an article on DigitalTrends: After months of analysis and experimentation, a team of researchers from Johns Hopkins University's Applied Physics Lab announced the successful development of a reliable sea-to-air UAV. Dubbed the Corrosion Resistant Aerial Covert Unmanned Nautical System -- or CRACUNS for short -- Johns Hopkins' drone has the ability to reside for months underwater without deteriorating or decaying. Once given the signal, the CRACUNS would then rise to the water's surface and begin flight, capable of undertaking a variety of missions.
In order for the drone to accomplish this, the team had to develop a body that contained no structural metal parts or machined surfaces. The composite-body had to not only be extremely lightweight, but able to be submerged in water and hold up to constant water pressure. CRACUNS project manager Jason Stipes said in a published press release, "Engineers at APL have long worked on both Navy submarine systems and autonomous UAVs. In response to evolving sponsor challenges, we were inspired to develop a vehicle that could operate both underwater and in the air."

Comments

TMA

[esampson]

CRACUNS, brought to you by the Department of Improbable but Possible Word and Acronym Development Services.

I've seen this before...

[spauldo]

Oh yeah, here.

Good concept, but.....

[Urinal Pube]

Unless this can park at a 500m depth, it will accumulate enough biomass to disable it in a matter of days. Also, looking at the shape of if, a simple machined aluminum hull would produce a cheaper, lighter, more durable hull, than any currently existing additive manufacturing technologies.

Re:Motors?

[gurnec]

I've watched the videos

Yes, but did you read the article? ;-)

For the motors that are exposed to salt water, APL applied commercially available protective coatings. The team tested the performance of the motors by submerging them in salt water. Two months later, they showed no sign of corrosion and continued to operate while submerged.

Barnacles?

[niftymitch]

If it was to sleep silently on the seafloor how does it protect itself
from colonizing creatures, sediment and detritus?

Sort of interesting...

Re:Good luck with the barnacles and weed etc.

[reemul]

If they've come up with an economically viable, environmentally friendly way to keep barnacles off for extended periods of time, that's a much bigger discovery than their little drone. Boat manufacturers would be pounding on their door and waving bags full of cash. So I'm guessing they're just hoping it won't be a problem and moving on rather than something they've seriously considered and have miraculously overcome.

Re:Good luck with the barnacles and weed etc.

[Sneftel]

You would be astounded, simply astounded, at what sorts of things a team of academics can rationalize away as something which, while not yet addressed, don't sound like difficult problems, and which aren't relevant to the publication at hand. That's particularly true when those things are a little outside the original team's wheelhouse, like a team of robotics engineers and physicists faced with the prospect of barnacles.