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DARPA Develops Dolphin-like Tail For Divers
willatnewscientist writes "Forget flippers, the latest idea from the guys at DARPA is a tail-like prosthetic for divers. The (forward-facing) tail, demonstrated at DARPA Tech 2007, is designed to help a diver maintain a speed of 2 knots for up to 300 metres. 'The unpowered, carbon-fibre structure straps to a diver's shins and is used with a motion that is not unlike the way Patrick Duffy swims in The Man from Atlantis. The design is inspired by the way mammals like Seals and Dolphins swim. I caught this video of Powerswim (3.5 MB .avi) at the DARPATech 2007 gathering in Anaheim, California. It would be nice to grab one and try it out when I next head down to the beach, but unless its designers DEKA (the same people who make the Segway) come up with a budget version, the $500 price-tag is going to keep me firmly in my flippers.'"
But it reminds me of this gadget I saw on TV somewhere. Its like a bicycle for travelling on water. It has the same two submerged wings but the rider sits above the water and pounds the machine up and down to keep moving (and dry).
This is a beautiful device. Short cord wings are always better once the materials are up to the job.
http://michaelsmith.id.au
I guess they are expecting that you have to be old enough to remeber the show to have money to buy their products. Has anybody in the 20-something age group even seen that show?
What the hell, that's gotta be the worst-encoded video I've ever seen! aLaw/uLaw audio? Never heard of it. And the video data seems to be much shorter than the audio data. All in all 3.5 megs for 1 second of video, and a few seconds of onlookers babbling undifferentiatedly.
No need to click and read the article. The summary *is* the article.
we just need some laser beams.
come up with a budget version, the $500 price-tag is going to keep me firmly in my flippers.'"
Personally, I think that a $500 price tag will result in this gaining widespread use, assuming it's as useful as the article states.
Why? People spend more than $500 all the time on bicycles, surfboards, skis, and other athletic equipment all the time. Matter of fact, I wouldn't be surprised if all the equipment for your typical diver exceeds $2k. A quick search shows new surfboards costing $300-400.
Worst case, it can be rented out to various tourists at $10/day and pay themselves off in well under a year.
I don't read AC A human right
For those of you not as comfortable with knots and meters(and with the help of google)...
2 knots = 3.37561971 feet / second
300 meters = 984.251969 feet
So it's about 3.4 feet/s over 984 feet.
Takes about 289 seconds, or 4 minutes 49 seconds.
Honestly, that's not as fast as I'd expect from DARPA equipment. Nor does it really have great endurance. *shrug* It's cool, don't get me wrong, but it seems like it'd be a long way away from USEFUL except in very, very specialized situations. Help me out, I can't actually think of any times where you'd want something like this if it only lasts 300 meters. In the time you're strapping that to your legs I'll already have swam most of the way there at a leisurely pace(and as a bonus, I don't have some dolphin fin to remove when I arrive.
Not a lot of information available, but found this http://www.darpa.gov/dso/thrusts/bio/biologically/ powerswim/index.htm/ that states that this device is 85% efficient, whereas typical recreational fins are only 10% efficient. Interesting, but does that mean that the device is going to be 75% more difficult to use that regular fins?
Ahhh, what an awful dream. Ones and zeroes everywhere... and I thought I saw a two.
It'd be cool if something like this was self-powered and could be controlled by EMG (the electric signals given off by contracting muscles), sort of like this prehensile tail that some folks made at the Telluride Neuromorphic Workshop a few years back:
e cts/EMGtail/emg_tail.html
http://www.isr.umd.edu/Labs/CSSL/horiuchilab/proj
if that isn't an oxymoron.
I watch BFM Paris news stream and a French swimmer is one of their top athletes. As someone who knows just enough to paddle instead of sink, I find it a little macabre to see how very, very much she undulates her whole body like a whale or something.
Mmmph. I dunno. This thing seems like an invitation for a shark to presume you are a nice, big fish.
Not to sound paranoid or anything, but I guess I'll let other people use them for a while first. ;-)
I've fallen off your lawn, and I can't get up.
They Call Him Flipper! Flipper!
Faster than lightning!
No one you see, is smarter than he!
And we know Flipper
Lives in a world full of wonder,
Lying there under, under the sea!
Everyone loves the King of the Sea
Ever so kind and gentle is he....
What's the difference between this new gizmo and old good monofin?
OTH it may make it possible to outrun a shark.
http://michaelsmith.id.au
As noted: 300 meters in 4.7 minutes. Uh, how many people can hold their breath for just under 5 minutes? Wait, I'll answer for you: Not even many SEALS I know can hold out that long without moving. This is really a piece of combat equipment to be used with oxygen and not for tourists OR a novilty. Swimmers already have monofins that can propel you "almost" as fast.
I hate slashdot
Outrun a shark? At 2 kph for 300 feet?
Methinks you aren't very familiar with sharks. A blue shark for instance is good for about 39 kph. In other words, if it wants you, you'll be had.
I've fallen off your lawn, and I can't get up.
Lasers!!
I want to play Free Market with a drowning Libertarian.
but unless its designers DEKA (the same people who make the Segway) come up with a budget version, the $500 price-tag is going to keep me firmly in my flippers. ~
hmmm... people shell out more than that for a ps3. doesn't seem too pricey for a government backed gadget.
According to The Register, the new fins will allow a diver to swim at a sustained 2 knots.
According to the first link returned by Google for "How fast can a great white swim": A great white's can swim about 20 knots -- in bursts. But, they usually swim around 1 or 2 knots.
So, the question is, who's got a better burst, a diver or a hungry shark? And who do you think can sustain that for longer?
Not too long ago, the Cincinatti Bengal's wide receiver Chad Johnson raced a horse. If anyone ever wants to race a shark, please let me know. I'm putting money on the shark.
Troll Like a Champion Today
I'm not sure if the guy patented it but I saw the exact same setup, I believe it was in Popular Science, thirty years or more ago. Dead serious on this one. It had the same front fin arrangement. I remember photos of him testing it in a swiming pool. I think he claimed more than 2 knots but it could have been exaggerated. I seem to remember it being more like 3 or 4 knots.
instead of posting these lame ass stories...
Every little bit of speed helps I suppose :)
http://michaelsmith.id.au
The Sun audio device handled aLaw/Law audio directly, and since they were the Microsoft of the UNIX world everyone else's "/dev/audio" devices work the same way.
This is like finding a file in BMP or WAV format, you go "oh, that's an oldschool DOS/Windows guy who doesn't know any better"... this is what you get when oldschool Sun/UNIX guys who don't know any better release stuff. It's no biggy... chuckle and move on.
I'll let other people have at it--until they make it possible to not have a giant wing oscillate so close to my nuts. That stupid thing is a castration catastrophe waiting to happen. No thanks.
Constitutional rights may be respected, repealed, or modified; but they must never be ignored.
SEALs turning into dolphins. Sounds like they're going backwards. And what do they do if it's a hot landing?
I'm not a jock, as you can tell because I'm posting to /. However, I do swim to lose my flab once in a while, and doing the breaststroke, which is a resting stroke, it takes me 50 minites to do a mile. That's 1.2mph (1.04 knots), which is half the speed of this thing.
Now, sure, going twice as fast would be pretty cool, even if it's only for 300 meters, but I can probably go that fast or pretty close just by changing to the crawl stroke and wearing flippers.
You don't need to outrun a shark, only the other guy who happens to be in the water nearby.
Personally, I think that a $500 price tag will result in this gaining widespread use, assuming it's as useful as the article states.
;-)
I've been diving for a couple of decades and this includes rare specialties where covering a lot of distance is useful. For normal recreational diving traveling around fast generally indicates a newbie. The point of diving is to enjoy the scenery and as divers become more experienced they generally slow down and become "lazy" and try to leverage currents and surges as much as possible.
A dolphin kick is something that divers occasionally do with normal fins to vary muscle usage and avoid fatigue and cramps. So many of us are somewhat familiar with the general style. The problem with this style is that it is quite limited with respect to maneuverability. Divers often use their legs/fins asymmetrically or at odd angles. This far more useful than going fast.
Finally, anything that makes your silhouette look even more like a seal to a shark is a bad idea.
You can't take the sky from me...
Don't sharks typically feed on things with large flippers that travel through the water? Human powered swimming aids are awesome, but shouldn't we try to make divers look a little less like a tasty seal?
2 knots an hour? for 300 m? I can do that with my legs....
Of course you can. The device is strapped to your legs after all.
When our name is on the back of your car, we're behind you all the way!
I might have the spelling incorrect but that's the brand name of a type of fin that does this already. It straps onto your calves with additional aluminum tubes and they keep your feet rigid and at the correct angle for maximum thrust using primarily your thigh muscles and not you calves. Similar in idea to this monofin, but still give you better directional control. Wear you out though., Joe navy seals and such like fooled around with them for a long time.
Especially if a shark thinks the guy using it is a meal. Move like seals and dolphins? Yeah... there might be something nipping at that idea.
~~ Behold the flying cow with a rail gun! ~~
A fairly decent distance, if I've had a chance to prepare myself, and especially if I have some very low tech diver's fins. I'll grant you that I couldn't go 300 meters on one breath, but I couldn't go the 300 meters with these things anyway. I'd have to hold my breath for 5 minutes.
If I was bobbing up for a breath every once in a while, then diving back down again these would convey some advantage certainly. The fact that they'd be doing some of the work for me means less O2 consumed and CO2 produced. But I still need to breathe. Probably a couple times over the course of 5 minutes of swimming.
These things don't seem to convey a very large advantage in this domain(yet) since they're so slow. It's not like you have an outboard motor strapped to your behind to REALLY add some speed to your swimming.
I'm hoping that these are just the first iteration in what will be a progressively more impressive technology. A low-end set of SCUBA equipment can be bought for less, and let me swim way, way further than 300 meters.
For the ammount of energy expended to move forward, as the other posters stated, no. It actually will take less effort to go faster, since its more efficient, thus more of your exerted power goes to moving you forward.
From a usability aspect, after watching the video of it in use, I have to say YES, it will be more difficult. Besides remembering to not extend your legs so far that the thing will hit you in the nuts, as you bring your legs back it extends down and away from you, just waiting to snag stuff on the bottom. This thing would only be good for swimming pools and open water where you have no intention of getting near the bottom.
SCUBA divers have a hard enough time as it is controling bouyancy so they can stay at a position close to the bottom without kicking up silt or breaking the delicate reefs. Having something like this just asks for trouble, and I seriously doubt any practial use for SCUBA exists. This being a DARPA project though, its more likely for military use such as covert SEAL ops requiring faster underwater swims. There it definately has potential, so long as they can shrink it down so its as small as/smaller than current fins when stowed, and can be put on/taken off just as quickly.
tm
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That's a big deal. Even dolphins can only manage to sustain twice this speed underwater, and they're much better swimmers than humans will even be.
Admittedly he's motionless, but fifteen minutes two seconds is pretty amazing: http://www.smh.com.au/articles/2007/08/10/11865305 69468.html
Denver's Aurora Reservoir counts as water. I suspect that quite a few people get their drinking water from there.
It's a mystery why people scuba-dive there, though. Apparently, there's so little to see that they plant items in there for scavenger hunts, and (if I read your fine article correctly) the water's so cloudy that if there was something to see, it would be hard to see it. Denver must not have any place better for the sport.
If anyone here wants to try scuba-diving in a landlocked state, I would recommend one of Kansas's many artificial lakes. Kansans put aquatic life in their water. Just watch out for the trees that are routinely dumped into the lakes for fish habitat...
There is a fine line between recklessness and courage... -- Paul McCartney
In my prime, after hyperventilating (not recommended for beginners), I could swim about 130 meters under water without the aid of fins. Now I'm old and not much good for anything.
This DARPA thing appears to be nothing more than a copy of the famous Aqueon invented back in the 1960's. You can find videos of it on YouTube, and even the original patent drawings are online which you could use to build your own: http://forums.deeperblue.net/freediving-equipment/ 53592-weird-fin-long-ago.html
Just google 'Aqueon swimming device'.
Swimming Machine
"Flex your legs, then kick out -- the Aqueon swimming machine enables you to out-speed an Olympic swimmer, says Pan Western Research. As your legs move, the forward plane rises and falls." -- Popular Science
(Popular Science, "What's New", June 1974)
You can see the old flyer at Innerspace Corporation.
Is DARPA missing something here? Apparently there aren't many finswimmers (see http://en.wikipedia.org/wiki/Finswimming) either at DARPA or here on /. Anyway, finswimming is swimming competition with a monofin - a single "flipper" that you wear on both feet like a dolphin tail. You swim by dolphin kicking. Now, in finswimming the world record for 400m is something like 2m48s - 2.4 m/s. Two knots is about 1.03 m/s according to Google. This tells me that a moderately-trained finswimmer can easily beat the invented contraption.
A competition monofin can be obtained starting at $250. I watched the video and the thing seemed pretty awkward as well. It seems that DARPA has invented something less efficient and more expensive than what was already available.
Just go directly at him and ram him. Anyway, from what I understand sharks aren't very intelligent and don't have great vision anyway. So unless this thing come with attached chum you're probably no better or worse off. Especially those delicious surfers (not that they use fins, but they make a damn fine fish silhouette).
Quack, quack.
Ted Ciamillo of the subhuman project has one as well called the Lunocet, full of titanium goodness and apparently to cost about 800 to 1500 dollars. http://www.subhumanproject.com/ Check out the link to the high speed diving section. Should be interesting, I am a keen spearfisherman so anything that can get me deeper with less effort is handy. Probably a bit out of my pricerange for a while though.
Doesn't look anywhere near as versatile as fins. Guess I'd have to actually use it to see, but what would kind of kick with this thing would be the equiv of doing a frog kick with your feet slightly up to avoid distrubing the silt at the bottom? Most of the good stuff is on the bottom, and if you are kicking up the silt, how are you going to see it? Am I missing something here?
I'll only eat dolphin if it's tuna-safe. :)
So DARPA has developed the AQUEON, http://www.abc.net.au/tv/newinventors/txt/s1106609 .htm , which was actually developed by an Australian in the 70's? Got to make you wonder why no one in our government every checks to see if they are giving out grants for developing stuff that's already been patented. I wonder how much we paid to "develop" something that was probably taken from the original inventor's patent drawings. Sounds like there wasn't much actual development work done, to me. I wonder how big the grant was.
-All that is gold does not glitter - Tolkien
www.ra
Er, whats the point?
300 metres - thats 12 lengths of a 25m pool. If 2 knots is 1m/S then you have 5 minutes to swim the 300 metres. 300 metres isn't a long way - triathlon guys swim a mile in open water (6400m) and I swim 1000m whenever I swim as part of my physiotherapy program for the injuries in my arms.
I'm 42, I have injuries in my arms that prevent me using too much power, but even so I can do 12 lengths of breast stroke in 6 minutes and if I did front crawl (freestyle) I'd be under the 5 minutes easily. I'm not a club or competition swimmer so although I'm faster than the average guy I'm not the fastest by a long way.
So I can beat that device without having it and I'm past my prime - is that device really solving a problem?
The type of people that I imagine would be interested in this would be already fit, competent swimmers - but the stats are that this device isn't that fast.
Just can't see the point, unless they are claiming it will help poor swimmers swim that fast - but poor swimmers won't have the technique for the legs (that leg action is very un-natural to use when swimming).
The monofin (backwards pointing) http://en.wikipedia.org/wiki/Monofin has been around since the Soviets introduced it in the early 70's.
I can't see how this new thing will generate any more thrust, or more efficient thrust than the monofin does, and it has to suffer from the same basic flaw, you get lots of thrust, but sacrifice maneuverability. (not to mention the monofin isn't going to crack you in the nuts.....)
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
As soon as I saw "reverse dolphin tail" I thought "Aqueon". And I wasn't alone; someone popped up on the New Scientist site giving credit to Gongwer.
Now the question: how many "inventions" could be brought out much faster or radically improved by not repeating the mistakes of the past, by knowing that past?
Maybe this bionic fin should be adapted to help keep the not-quite-extinct Bajii out of trouble?
I just thank the Lord she didn't live to see her son as a mermaid!
Mer-MAN! Mer-MAN!
You're using her as bait, Master!
It kinda makes you wonder about our preocupation with the sea. I used to surf a lot before I moved waaaaay inland on an entirely different coast. Anyways as I sat on my board and looked at all the individuals in the line-up. I used to think that there might be something more to it than just our love of surfing that brought us here into an alien wilderness. Was there something biological going on that makes some prefer the water as opposed to more terrestial types? It's just a thought.
The device looks very promising. I would love to own one. At it's current price level I think I'll wait, LOL! In any event, seals, sea-lions, dolphins, and SHARKS will have drop on you whenever they feel like it. That is unless you strap a torpedo on your back with a rudder.
I took Vladmir Walters Fish Biology course many years ago at UCLA. Walters was an avid, early investigator of fish hydrodynamics and much of the class deal with issues associated with swimming. During one lab we went to a location in West LA where a gentleman demonstrated a relatively simply underwater attachment similar to this forward facing flipper that permitted him and some of us students to swim around the pool at remarkable speeds. According to him, he demonstrated in to the military, by swimming from Santa Catalina Island to the mainland. He said you could often "sneak up on sharks", typically blue sharks and bull sharks, he believed because their lateral lines could not detect his presence until in close proximity. He said the military showed on limited interest at the time and I never heard if they ever attempted to employ it for their purposes.
He was trying to sell it too, for about $150. I saved the flyer for many years thinking someday I would have that kind of money, but lost it sometime later. It was quite remarkable. I just regret I didn't follow up on it or even now remember his name. A man ahead of his time.
Any other members of the class remember his name and other aspects of the design?
you would look more like a big chunky dolphin, which most of the time sharks will avoid confrontation with. That's not to say that sharks are scared of dolphins, they usually win in a fight, but a dolphin would put up a much bigger fight than most fish, and usually get away, so as far as the shark is concerned, it's just too much hassle to eat a healthy dolphin. A shark is far more likely to go for you if you are splashing about in flippers, as you would appear more like an injured animal to him.
What if Tetris was invented by Nazis?
Not sure exactly when but I watched an article about this on Tomorrows World a BBC science program sometime between May 1965 and September 1967 (That was the period that my family were based in Northwood. I know it was then because I wanted one and tried to make my own in the workshop that house had).
The world record for the men's 1500m is held by Grant Hackett at a time of 14:34.56 http://en.wikipedia.org/wiki/World_record_progress ion_1500_metres_freestyle.
l es&ie=utf-8&oe=utf-8
h +to+knots&btnG=Search
1500m = 0.932056788 miles http://www.google.com/search?rls=en&q=1500m+to+mi
so that's a speed of about 3.8 miles per hour.
3.8mph is 3.3 knots http://www.google.com/search?hl=en&rls=en&q=3.8mp
Actually, with a proper scooter you don't have to hold on tight. The tow cord clips on to your harness. And there is no need to keep your legs stiff either; they need to be relaxed and out of the slipstream for maximum speed.
You take the silly contraption and I'll take a standard recreational DPV (such as the Oceanic Mako) which is twice as fast, goes for 2 hours, is cheaper, and I an do all kinds of underwater maneuvers while you wear the overpriced flippy thing.
You forgot that swimming underwater is much much slower than swimming at the surface. Also it's much harder to use your arms (and your legs too) underwater as effectively as at the surface. Add a bunch of equipment strapped to you, and it makes things even harder. So they're probably making much larger gains with this device than what your calculations indicate.