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DARPA Develops Dolphin-like Tail For Divers

Zonk posted more than 6 years ago | from the chimera-tech dept.

Robotics 146

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.'"

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146 comments

Can't wait to try it out (2, Insightful)

MichaelSmith (789609) | more than 6 years ago | (#20198737)

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.

I am eating DOLPHIN right now! (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#20198921)

As in dolphin fish, mahi mahi. Very good h'orderve if you ask me!

Eat pork. Live forever.

Re:I am eating DOLPHIN right now! (2, Insightful)

fyngyrz (762201) | more than 6 years ago | (#20199017)

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. ;-)

Re:I am eating DOLPHIN right now! (1)

MichaelSmith (789609) | more than 6 years ago | (#20199117)

This thing seems like an invitation for a shark to presume you are a nice, big fish.

OTH it may make it possible to outrun a shark.

Re:I am eating DOLPHIN right now! (3, Informative)

fyngyrz (762201) | more than 6 years ago | (#20199211)

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 [elasmo-research.org] . In other words, if it wants you, you'll be had.

Re:I am eating DOLPHIN right now! (1)

MichaelSmith (789609) | more than 6 years ago | (#20199295)

Outrun a shark? At 2 kph for 300 feet?

Every little bit of speed helps I suppose :)

Re:I am eating DOLPHIN right now! (4, Funny)

mobby_6kl (668092) | more than 6 years ago | (#20199505)

You don't need to outrun a shark, only the other guy who happens to be in the water nearby.

You're forgetting the nose piece... (1)

msimm (580077) | more than 6 years ago | (#20200485)

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).

Re:I am eating DOLPHIN right now! (2, Funny)

mike_the_kid (58164) | more than 6 years ago | (#20199229)

According to The Register [theregister.co.uk] , 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.

Re:I am eating DOLPHIN right now! (2, Funny)

modecx (130548) | more than 6 years ago | (#20199335)

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.

Man From Atlantis? (2, Interesting)

Picass0 (147474) | more than 6 years ago | (#20198817)

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?

Re:Man From Atlantis? (0)

Anonymous Coward | more than 6 years ago | (#20198917)

I'm 27, so around here I'd say no one under 25 saw it. It was quite popular at the pool back then, though ;)

Re:Man From Atlantis? (0)

Anonymous Coward | more than 6 years ago | (#20198999)

I'm 27, so around here I'd say no one under 25 saw it. It was quite popular at the pool back then, though ;)
So were your "kids" when you were "dropping them off," lol

Oh, and since slashdot is making me wait for six minutes before I post this reply, please lick my balls, moderators. This post was meant to be funny, but it is now a troll post. Suck the feces out of my anus with a vacuum. Here in Industrial Europe, you may find many vacuums with sufficient capacity.

Eleven minutes now (ELF) and I am angry. I wish that everyone reading this would die from a toxic serum. While struggling to breathe the last breaths of life, I wish that this person would suck my balls into oblivion. I can orgasm from this stimulation.

Fourteen minutes (for you English, vier + zhen), I request to lick the inside of my anus. I believe this to be almost a "redundancy" of my original post, but I have no more hatred to distribute to such a worthless site.

Re:Man From Atlantis? (0)

Anonymous Coward | more than 6 years ago | (#20199153)

Are you suffering from internal parasites?

Re:Man From Atlantis? (0)

Anonymous Coward | more than 6 years ago | (#20199207)

Nein

Re:Man From Atlantis? (1)

PitaBred (632671) | more than 6 years ago | (#20199991)

Nine? That's a lot of parasites... bet it's a hell of a diet, though

Re:Man From Atlantis? (1)

gold23 (44621) | more than 6 years ago | (#20200313)

Here in Industrial Europe, you may find many vacuums with sufficient capacity.

Are you suffering from internal parasites?

No, he's just full of shit.

Encoding (0, Troll)

Anonymous Coward | more than 6 years ago | (#20198839)

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.

Re:Encoding (1)

Brian Gordon (987471) | more than 6 years ago | (#20199037)

And since when is "avi" useful information to put next to the link? It's just a container format..

Re:Encoding (1)

FooAtWFU (699187) | more than 6 years ago | (#20199055)

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.
I've heard of it.... in an academic context. Basically, it's a logarithmic mapping of standard uncompressed audio data sample levels. This makes your crappy 8-bit samples a little less crappy: you don't need as fine-grained of a difference between sample levels when the sample levels are very loud. Preception of volume levels is essentially logarithmic too, so this makes sense. It's not uncommonly used in .au files, I think.

Mind you, that's no excuse to be using it in modern video files for Internet consumption.

You never used a Sun, I guess... (2, Interesting)

argent (18001) | more than 6 years ago | (#20199313)

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.

Re:You never used a Sun, I guess... (0)

Anonymous Coward | more than 6 years ago | (#20199809)

Heh, actually I have, but just as a regular user and the actual hardware was quite concealed from me. I guess I could have found out, but to be honest I don't know much about SunOS/Solaris (that's probably the first thing I should try to get straight).
Anyway, I now suspect that the guy's digital camera (or mobile phone) produced that video, partly because it's small and silly, and partly because the video data is encoded as Motion-JPEG (that is, not necessarily, but possibly (I don't really know) nothing more sophisticated thab a JPEG every frame).
Anyway, thanks for the info :)

RTFA (4, Funny)

Anonymous Coward | more than 6 years ago | (#20198869)

No need to click and read the article. The summary *is* the article.
 

now, (3, Funny)

martinelli (1082609) | more than 6 years ago | (#20198881)

we just need some laser beams.

Re:now, (2, Funny)

firpecmox (943183) | more than 6 years ago | (#20198923)

we just need some laser beams.
And attach them to the head of some friggin sharks.

Re:now, (1)

datapharmer (1099455) | more than 6 years ago | (#20198963)

you must have been absent recently [slashdot.org] ...

Re:now, (1)

Tablizer (95088) | more than 6 years ago | (#20199231)

we just need some laser beams.

With extra Frikken(tm) chips so that we can have Frikken laser beams.
     

$500 - not a bad price (5, Insightful)

Firethorn (177587) | more than 6 years ago | (#20198919)

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.

Re:$500 - not a bad price (4, Insightful)

Anonymous Coward | more than 6 years ago | (#20198971)

Its not uncommon for people to spend $120-$150 on normal fins for scuba diving. Some free diving (holding your breath and swimming to depth) fins can go for over $200. The Omer Millennium Carbon Rekord III has a MSRP of $504 (this sells for $420 online).

So I'd think that a $500 fin if useful could have quite a market. Recreational divers would probably just use underwater scooters if they really needed to go a great distance from their entry point so I'm not sure how hot they'd be on having to kick it themselves. Not to mention that during the fun part of the dive people like to be able to go at a slow speed so they can see things so they'd need to bring normal fins too.

Re:$500 - not a bad price (2, Interesting)

Firethorn (177587) | more than 6 years ago | (#20199177)

Dude - either uncheck the AC comment or get an account. This is a good post.

Good point about the cost of normal fins. That was part of my point - $500 is relatively cheap for many forms of sporting equipment.

Not to mention that during the fun part of the dive people like to be able to go at a slow speed so they can see things so they'd need to bring normal fins too.

The way I see this operating, it'd be a lot like a more efficient type of fin. It's not like they couldn't just flip it slower if they wanted to go slower. IE if they want to look at something a little ways away, they can travel there faster with less effort. Without going back to the scooter

Re:$500 - not a bad price (1)

aaarrrgggh (9205) | more than 6 years ago | (#20200423)

$500 is perfectly reasonable, agreed. But the underwater scooters are hard on air consumption (you have to hold on tight and maintain leg stiffness for proper control). If the super fin works well both for high speed and low speed motion, it sounds like a winner.

Personally, I'll stick with my Quattros. Scuba diving is all about moving as little as possible... but having the extra power when you have to fight a current.

Re:$500 - not a bad price (1)

yfarren (159985) | more than 6 years ago | (#20198975)

2 knots an hour? for 300 m? I can do that with my legs....

Re:$500 - not a bad price (3, Informative)

gujo-odori (473191) | more than 6 years ago | (#20199089)

To put the speed in perspective, 2 knots/hours is roughly double the speed of the world record holder in the men's long course 800 meter freestyle. Even allowing for fins, and for being under water, I rather doubt you could swim that far, that fast, with your legs.

Plus, of course, if a person could swim that far, that fast, with their legs do you really think DARPA would have spent the money do develop this device?

Re:$500 - not a bad price (2, Interesting)

Firethorn (177587) | more than 6 years ago | (#20199139)

I did some research - human swimming speed record is 2.29 m/s, which is around double the 'More than 2 knots' quoted in the article. While unaided - Tom Jager also wasn't encumbered by air tanks and only covered 50 meters in his run.

Still, I doubt their guinea pig was a world-class swimmer or diver.

If it really does increase efficiency from 10%(tourist fins) to 85% like another poster said, I can see it being really popular among serious divers. For one thing, it's probably less intrusive than a scooter.

Re:$500 - not a bad price (1)

danlock4 (1026420) | more than 6 years ago | (#20199247)

2 knots = 2 nautical miles per hour = 2.3 mph = 3.7 kph

Of course you can... (1)

camperdave (969942) | more than 6 years ago | (#20199615)

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.

Re:$500 - not a bad price (2, Funny)

geobeck (924637) | more than 6 years ago | (#20200133)

2 knots an hour? for 300 m?

That's a hell of a distance over which to sustain that degree of acceleration. ;)

Re:$500 - not a bad price (1)

MadnessASAP (1052274) | more than 6 years ago | (#20200519)

It's not the distance that will kill you its the time ~24 seconds in this case at which point you're doing ~48 knots and probably really, really tired.

Re:$500 - not a bad price (1)

pescadero (1074454) | more than 6 years ago | (#20198989)

But, all those things you listed are necessary for their respective activities. You can't ski without skis or surf without a surfboard.

However, you *can* swim underwater without the Powerswim. How much more effective is the Powerswim than ordinary flippers? Is it worth the $490 increase in price?

Or if you want to go faster, you can spend $150 to buy a motorized waterscooter that goes 3 times faster than the Powerswim.

Obviously I've never Powerswimmed so I don't know how great it is, but it would have to be a completely different experience than flippers & waterscooters to be worth that price.

Re:$500 - not a bad price (1)

Firethorn (177587) | more than 6 years ago | (#20199101)

But, all those things you listed are necessary for their respective activities. You can't ski without skis or surf without a surfboard.

Golf clubs? Monogrammed golf balls? Bowling Balls? Basketball shoes? MP3 players(and impact resistant CD players before that), treadmills, stationary bikes, etc...

I can go to walmart and buy a perfectly usable bike for $150, or go to a specialized bike shop and spend $2k or more for a really, really good bike. The same thing with golf clubs and bowling balls. Heck, look at archery. There's all sorts of sights and release aids that aren't strictly necessary that people willingly spend money on.

However, you *can* swim underwater without the Powerswim. How much more effective is the Powerswim than ordinary flippers? Is it worth the $490 increase in price?

I wouldn't know, I'm not a diver nor a power swimmer. I like to swim, but I've only used fins like once. What I'm basing the idea that it'll sell on is that people will spend huge amounts of money for their sports equipment, even if they don't technically need to.

Some quick research indicates that an underwater scooter is closer to $250 than $150, and only gets you another .3m/s over the 'tail'. The one I saw said '1 hour under normal usage'. So it requires charging and maintenance that this device probably doesn't need.

Re:$500 - not a bad price (2, Interesting)

MichaelSmith (789609) | more than 6 years ago | (#20199175)

I can go to walmart and buy a perfectly usable bike for $150, or go to a specialized bike shop and spend $2k or more for a really, really good bike. The same thing with golf clubs and bowling balls. Heck, look at archery. There's all sorts of sights and release aids that aren't strictly necessary that people willingly spend money on.

I am a bike rider and a snorkeler and this article has got me thinking about integrating some sort of power assisted snorkel with it. Swimming under water is more efficient than being on the surface, so being a metre down with fins like these would be a big advantage. You can't suck air to that depth with your lungs but it might be possible to use the motion of the rig to pump air from the surface and into a mouthpiece. Athletes already learn to synchronise breathing with body motion.

Re:$500 - not a bad price (1)

Bluesman (104513) | more than 6 years ago | (#20199165)

Have you ever been to California? People out here will spend thousands on any ineffective new sporting equipment that will make them look even slightly more ridiculous than the previous fad.

Mountain unicycling comes to mind. Yes, it exists.

Re:$500 - not a bad price (1)

networkBoy (774728) | more than 6 years ago | (#20200253)

Please tell me that's an LA thing!
Here in NorCal we would normally expect that from San Francisco, but on those streets it would be suicide, if not from the hills, then from the cars (specifically their drivers).

On a side note, I've always wanted to line up a jump from Van Ness over the last bit of obstacles and into the bay and do it on rollerblades...
Again, suicide...

Re:$500 - not a bad price (0)

Anonymous Coward | more than 6 years ago | (#20199077)

Gear for diving costs approximately $1500 for basic cheap new equipment (including your life support stuff, basic suit and other crap).
A pair of standard fins will cost from $50 to about $200-something. This is looking to be at least 2x as expensive and up to about 10x as expensive.
Unless there is a marked improvement with this device it probably is not worth it.

You also have to consider burden. If this device decreases mobility in specific area (like near surface/floor or penetration diving) then it is even less useful.
I would probably put my $500 into getting a slightly better BC or regulator. For $500 one can pick up a computer. For the amount of time one is underwater it seems all the more useful and practical to me. The biggest benefit would be decreased air consumption if it requires substantially less energy to move with this thing (which affects your bottom time if you breath like an overexcited 14 year old). But even with reduced air consumption, how much of an effect would it have? I do not think that most recreational divers go anywhere near max ventilation or even a level that a reduced load would lower air consumption enough to warrant the price tag. Loads when diving are just not that great. I never checked my breathing rates while underwater.

I am sort of diving on a budget though. This shit is expensive. But with no budget maybe I would check something like this out. Most people who dive can afford to spend an extra $500 though. If it is easy to use and does not encumber the individual it will can on. Dive shops love to sell the newest thing. It is a hobby for people who have too much money and happen to live near water.

Re:$500 - not a bad price (1)

Firethorn (177587) | more than 6 years ago | (#20199253)

I suggest getting an account.

Gear for diving costs approximately $1500 for basic cheap new equipment (including your life support stuff, basic suit and other crap).

So I wasn't far off. When posting prices for stuff like this, I tend to assume new equipment, as that's easiest to get and more stable in price than used. I also tend to take a step or two up from the cheapest(with research into quality). So $2k is about right.

Unless there is a marked improvement with this device it probably is not worth it.

There's a difference between 'not worth it' and 'people won't buy it'. There's all sorts of useless junk people will buy, as well as useful stuff that'll sit on the shelf forever.

I would probably put my $500 into getting a slightly better BC or regulator. For $500 one can pick up a computer.

But what do you do once you have the better BC, regulator, and computer?

The biggest benefit would be decreased air consumption if it requires substantially less energy to move with this thing

According to one poster, it's 85% efficient as opposed to 10% efficient with normal fins. I figure 20% for 'good' fins - so it'd cut your expenditures in movement by a factor of four. Still not a lot over the air demands for simply keeping you alive, but it's something.

I do not think that most recreational divers go anywhere near max ventilation or even a level that a reduced load would lower air consumption enough to warrant the price

I would tend to think that 'tourist divers' would use these things(assuming it's usage doesn't take long to learn), more because it makes swimming around easier, increasing their range due to limited muscle fitness for swimming than any air demand(which they won't push).

I am sort of diving on a budget though. This shit is expensive.

I know. I'm agonizing over buying a $500-700 bike coming up. My old one is just worn out. The $150 walmart special doesn't cut it for me though.

But with no budget maybe I would check something like this out. Most people who dive can afford to spend an extra $500 though. If it is easy to use and does not encumber the individual it will can on. Dive shops love to sell the newest thing. It is a hobby for people who have too much money and happen to live near water.

My point. Offer it as a rental, offer free lessons, and you'll get people buying it. Especially if it works. If the price eventually drops to $200, so much the better for us. Meanwhile let the rich yuppies buy them. Until then, you might eventually be able to pick up a used one cheap.

Re:$500 - not a bad price (1)

PitaBred (632671) | more than 6 years ago | (#20200077)

You don't necessarily even have to live near water [denverpost.com]

Scuba-diving in the Aurora Reservoir (1)

Anonymous McCartneyf (1037584) | more than 6 years ago | (#20200221)

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...

Re:$500 - not a bad price (4, Insightful)

malkavian (9512) | more than 6 years ago | (#20199265)

I'm a diver, and I'd shell out $500 for a pair.. And yep, my diving kit exceeds 2k. Double that and you start to be in the right area.
Fins are one of the areas that I'd love to be able to get more power from without increasing my fatigue. If someone comes up with a way of doubling my speed, while keeping my air consumption constant, I'd leap at it.
While you're under water, everything you carry keeps you alive, and fins, often forgotten, are critical in keeping you effective in a current. There's been the odd time or two, when I've been caught in an unexpected stream, and being forced to cling to rocks to stop myself being pushed either off course (bad) or down (worse). At times like that, when being faced with a downdraught to 70m or more, you'd gladly pay all you had, and more, just to give yourself the best chance of surviving the dive. Sadly, you don't get the option when the most need it; you have to pay in advance, and hope you never need it..

On the fun side, it'll double your range if you get twice the speed, with no increased air consumption. That means more to see with each dive. Not sure you can do a wreck penetration with one of those on you though. Too much opportunity for it to snarl, and kick up the silt. And one thing you don't want is to be stuck inside a wreck, and have the world go dark (yes, you can get zero visibility quite easily from a badly executed fin kick or two in silty conditions).

Re:$500 - not a bad price (1)

camperdave (969942) | more than 6 years ago | (#20199659)

I've only dove once, but it seems to me that once you're inside the wreck, there's very little need for increased swim speed. Use these to get to and from the wreck, and leave them "parked" outside while you explore.

Re:$500 - not a bad price (1)

aaarrrgggh (9205) | more than 6 years ago | (#20200441)

Not all diving is in wrecks... but in a wreck you want something that doesn't create too much vertical turbulence, which will stir up silt. Curious how this would do there...

These fins are too limited in maneuverability (2, Informative)

AHumbleOpinion (546848) | more than 6 years ago | (#20199565)

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. ;-)

Re:These fins are too limited in maneuverability (1)

Firethorn (177587) | more than 6 years ago | (#20199913)

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.

I was thinking 'the next bend of reef over distances'. Of course experienced divers are going to learn all the tricks to make moving easy.

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.

Which would indeed be a concern, and might kill this device for normal usage. Still, if it can be made to still allow you to do that...

Finally, anything that makes your silhouette look even more like a seal to a shark is a bad idea. ;-)

Agreed, though remember, this thing faces backwards. Didn't look too seal-like to me. More like a hook.

Re:These fins are too limited in maneuverability (1)

aaarrrgggh (9205) | more than 6 years ago | (#20200499)

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.


I was thinking the same thing... the versatility of a normal rigid fin seems nicer than a "high speed" fin. Haven't tried doing a dolphin kick with a split fin, but not sure how you might be able to do something along the lines of sculling with this would seem like a challenge.

Re:$500 - not a bad price (1)

fishbowl (7759) | more than 6 years ago | (#20200347)

>I wouldn't be surprised if all the equipment for your typical diver exceeds $2k.

A good regulator runs $300 to $500. You can spend $700 or $1000 in a dive shop on a regulator, and professional divers will spend a lot more than that. A good cold water wetsuit is easily upwards of $500; way more than your typical surfing suit. It's so easy to spend five grand on diving equipment it's not even funny; and let's don't even talk about what dive enthusiasts have in their *boats*, *motor homes*, *hotel bills*, and *airfare*.
A $500 marginal cost isn't all that significant to a real diving enthusiast, especially not for one who is into deep dives.

Don't get me wrong -- you can rent a whole package, get some safety training, etc., for like $50 to $100 a day, all over the Caribbean, if you don't mind doing the group thing. But you ought to be able to get the lecture, pool lesson, equipment and a good day's worth of a reef dive for under a hundred bucks at pretty much any resort.

Conversions and comments (3, Informative)

Kandenshi (832555) | more than 6 years ago | (#20198949)

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.

Re:Conversions and comments (1)

MichaelSmith (789609) | more than 6 years ago | (#20198973)

I can't actually think of any times where you'd want something like this if it only lasts 300 meters

How far you go depends on the user. In general I think scuba gear has it easy on the oxygen supply side. The leg muscles which drive your fins can only use so much oxygen. By using muscles in the torso to push the wings up and down you do more work for more return and (probably) use more air.

For me this is a bit like the difference between open pedals and clipless pedals on a bicycle. The former case has poor power transfer and performance, but doesn't load the metabolism so it is good for Your Mum to use. Attach your feet to the pedals and you immediately need to be a lot fitter but you can go very fast and have more endurance.

Maybe we will now see people swimming the English channel under water or doing underwater endurance races.

Re:Conversions and comments (1)

Firethorn (177587) | more than 6 years ago | (#20198979)

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.

What if you don't have to remove it? The article states that it was developed from studying marine mammals. They have their shape 100% of the time, and they can do all sorts of stuff. So, baring anything unusual, you shouldn't have to remove the device for the entire dive.

If it allows the high speed as a result of increased swimming efficiency, it could help casual divers as well - increasing their speed or reducing their effort per distance traveled.

It sounds a bit like a water based bicycle - which both increases maximum speed and reduces effort.

Re:Conversions and comments (2, Insightful)

gujo-odori (473191) | more than 6 years ago | (#20199003)

Very, very specialized situations? Uhh, this *is* DARPA we're talking about here, so it's pretty likely those are just the situations they had in mind.

Re:Conversions and comments (0)

Anonymous Coward | more than 6 years ago | (#20199511)

I agree. And with fins you would be much, much faster. Something is not correct here.

J.

Takes about 289 seconds, or 4 minutes 49 seconds. (1)

Scrameustache (459504) | more than 6 years ago | (#20199577)

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.
How far can you swim while holding your breath?

Re:Takes about 289 seconds, or 4 minutes 49 second (1)

Kandenshi (832555) | more than 6 years ago | (#20199915)

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.

How far can you swim while holding your breath? (1)

fuego451 (958976) | more than 6 years ago | (#20200239)

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.

Re:Conversions and comments (0)

Anonymous Coward | more than 6 years ago | (#20199905)

oh no what's a fucking meter, i have to tell people this shit

Re:Conversions and comments (2, Insightful)

Trouvist (958280) | more than 6 years ago | (#20200361)

Seeing as how I was a competitive swimmer in highschool and college, we would often do 100 meters in around 1:30 for warmup. Consequently, 300 meters would take 4 minutes and 30 seconds; basic swimming, not even getting out of breath. We could go THOUSANDS of meters at that pace (which is still faster than what this contraption does). So technically, this really isnt all that fast.

85% efficiency (3, Informative)

K.os023 (1093385) | more than 6 years ago | (#20198955)

Not a lot of information available, but found this http://www.darpa.gov/dso/thrusts/bio/biologically/ powerswim/index.htm/ [darpa.gov] 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?

Re:85% efficiency (1)

tantaliz3 (1074234) | more than 6 years ago | (#20199019)

Interesting, but does that mean that the device is going to be 75% more difficult to use that regular fins?
No, it means that for the same amount of energy you use getting from a-b with regular flippers, you can do ~a-b-a-(b)1/2

Re:85% efficiency (1)

Omnedon (701049) | more than 6 years ago | (#20199083)

It means that you would be able to keep pace with a swimmer using conventional fins while expending far less energy or expend the same energy and get there quite a bit faster. Much like a more efficient car using less fuel for the same distance (or go faster with the same fuel use, but the police tend to frown on that).

Re:85% efficiency (1)

danlock4 (1026420) | more than 6 years ago | (#20199279)

Mod parent up! It's very informative.

More efficient, yes, easier to use, NO (2, Interesting)

Tmack (593755) | more than 6 years ago | (#20200037)

Not a lot of information available, but found this http://www.darpa.gov/dso/thrusts/bio/biologically/ powerswim/index.htm/ [darpa.gov] 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?

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

Control by muscle signals? (1)

FleaPlus (6935) | more than 6 years ago | (#20198969)

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:

http://www.isr.umd.edu/Labs/CSSL/horiuchilab/proje cts/EMGtail/emg_tail.html [umd.edu]

Extending the "mainstream state-of-the-art"? (1)

smchris (464899) | more than 6 years ago | (#20198991)

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.

Re:Extending the "mainstream state-of-the-art"? (1)

weak* (1137369) | more than 6 years ago | (#20199061)

I watch BFM Paris news stream
The researchers will have to rerun their fluid dynamics simulations with wine as the transport medium and make some adjustments before this will serve your needs.

(BTW, not hating on the French--they account for half of my ancestry.)

Flipper! (2)

Alien Being (18488) | more than 6 years ago | (#20199041)

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....

Monofin? (1)

snikulin (889460) | more than 6 years ago | (#20199043)

What's the difference between this new gizmo and old good monofin [wikipedia.org] ?

Re:Monofin? (2, Informative)

MichaelSmith (789609) | more than 6 years ago | (#20199097)

What's the difference between this new gizmo and old good monofin?

The monofin is longer and narrower so it has more parasitic drag. This device is more like a high aspect ratio sailplane wing, while the monofin is at best like an old style hang glider.

The Aqueon did this 40 years ago! (2, Interesting)

Traf-O-Data-Hater (858971) | more than 6 years ago | (#20200247)

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 [deeperblue.net] Just google 'Aqueon swimming device'.

I would rather have... (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#20199103)

a dolphinoplasty!

http://www.youtube.com/watch?v=G_aNgs3yK5M [youtube.com]

wait...... (2, Insightful)

proadventurer (1071064) | more than 6 years ago | (#20199179)

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.

Re:wait...... (1)

grommit (97148) | more than 6 years ago | (#20199875)

I guess you missed the part in the article that said it was meant for divers?

Re:wait...... (1)

rindeee (530084) | more than 6 years ago | (#20200053)

'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.' Ooooo...your sharp, biting whit and grasp of the obvious is striking. Though in the future you might consider SCUBA gear. And as for NAVSOC/NECC (SEALs et al), they would love to use this sort of thing with a Dräger. Know a lot of SEALs do you? Jackass.

Re:wait...... (0)

Anonymous Coward | more than 6 years ago | (#20200215)

This could quickly become a pissing match, but the SEALs -I- know (doesn't everyone on Slashdot know a few?) don't like messing around with 'new' (read: experimental) stuff, and love their standard flippers. If they need to do something truly crazy, they've got SBUs to help them out. And, sure, sure... some guys -DEVGRU, perhaps?- might try it out, but I bet they're not doing cartwheels over some newfangled device DARPA cooked up to make 'em swim a tiny bit faster while looking rather uncool.

Re:wait...... (1)

proadventurer (1071064) | more than 6 years ago | (#20200331)

Gosh, you really hurt my feelings. Good luck in life.

Next prosthetic... (2, Funny)

CptPicard (680154) | more than 6 years ago | (#20199213)

Lasers!!

pricey? (0)

Anonymous Coward | more than 6 years ago | (#20199219)

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.

They may want to check with the patent office (2, Interesting)

edwardpickman (965122) | more than 6 years ago | (#20199243)

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.

Re:They may want to check with the patent office (1)

TihSon (1065170) | more than 6 years ago | (#20199695)

Funny to see your comment, as I was thinking the same thing when I read the /. header ... and I also remember the pool video ...

It's the Aqueon, "What's New" in June 1974! (4, Informative)

ClayJar (126217) | more than 6 years ago | (#20200375)

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 [innerspacethrusters.com] .

It's Saturday night, take some time off (1)

CorbaTheGeek (1037074) | more than 6 years ago | (#20199293)

instead of posting these lame ass stories...

this is useful (2, Insightful)

NRISecretAgent (982853) | more than 6 years ago | (#20199351)

SEALs turning into dolphins. Sounds like they're going backwards. And what do they do if it's a hot landing?

I'm not impressed (1)

Fear the Clam (230933) | more than 6 years ago | (#20199357)

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.

Re:I'm not impressed (1)

bigbe (1141419) | more than 6 years ago | (#20199935)

I agree, it does sound slow. They've got to have better things to spend their time on. (Like improving the Segway?)

Re:I'm not impressed (1)

networkBoy (774728) | more than 6 years ago | (#20200337)

Want to lose flab? one word: Butterfly.
Once your cardio gets to the point that you can do one full lap without gassing, start alternating one fly one breast or back to catch your wind, then up it to 2:1, 3:1 as you gain. It was my favorite stroke till I got sidelined and fell out of shape.
-nB

What a great idea... (0)

Anonymous Coward | more than 6 years ago | (#20199581)

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?

Faralons (0)

Anonymous Coward | more than 6 years ago | (#20199749)

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.

Something is nibbling at this idea... (1)

CFBMoo1 (157453) | more than 6 years ago | (#20199891)

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.

It's swimming underwater (1)

YU Nicks NE Way (129084) | more than 6 years ago | (#20200045)

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.

I am not impressed (0)

Anonymous Coward | more than 6 years ago | (#20200475)

Is DARPA missing something here? Apparently there aren't many finswimmers (see http://en.wikipedia.org/wiki/Finswimming [wikipedia.org] ) 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.

Subhuman has already built one (1)

fatovich (770355) | more than 6 years ago | (#20200517)

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/ [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.
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