It’s obscure but there was such a contraption trialled by the seals and cia in the 1950s http://www.hisutton.com/CIA_Water-Air_1958.html
Here’s a pedal powered smuggling submarine from the 1940s http://www.hisutton.com/Swiss-Pedal-Powered-Smuggling-Submar...
I swim because I enjoy it, not because I'm trying to get somewhere fast.
This seems awkward and I bet you have to use your arms just to counterbalance the twist you'd get on each 'stroke' of the leg.
So even though I think it's goofy, I bet I'd like whoever came up with this. Someone who put a ton of effort into building something they thought would be interesting despite a thousand people telling them it's goofy.
Good on them.
I swim because I enjoy it, not because I'm trying to get somewhere fast.
I run because I enjoy it, not because I’m trying to get somewhere fast. But I also bike because I enjoy it, not because I’m trying to get somewhere fast.
You seem to assume that because this thing is faster, it must automatically be less enjoyable. That’s not the case for bikes, why should it be the case here? In my opinion it sounds fun, and would probably be enjoyable.
Maybe not necessarily "faster" but there is an idea that adding any kind of technology should be avoided for recreational activities. For example, you can mountain bike with a fully-suspended e-bike, or you can struggle with a hardtail or even a road bike. Different kinds of fun, but in the former you'll wonder if it's the technology doing all the work.
there is an idea that adding any kind of technology should be avoided for recreational activities
How do you draw the line at "any kind of technology"? Isn't the bike itself "technology"? How about pneumatic tires? Or computer designed tread for optimal traction? Is a bike suspension too much technology? How about electric assist that can help you up a hill but won't propel the bike without you pedaling along with it?
Draw the line wherever you want, this isn't some kind of absolute theory of anything. Just that adding stuff to maximize your output isn't necessary to have fun.
Different kinds of fun, but in the former you'll wonder if it's the technology doing all the work.
"All the work" is useless hyperbol. There are things that simply can't be done on a road bike. There are things that can be done on a road bike without a significant loss of safety.
Sport technology can reduce the skill required for certain things, but it also tends to extend the envelope of what is possible. It is almost never correct to think of technology doing all the work but rather to think of it as an ability multiplier.
There are of course, times when it is beneficial to practice without a specific piece of equipment. Either for a challenge or/and to hone a specific sub skill.
there is an idea that adding any kind of technology should be avoided for recreational activities.
That's a pretty weird idea.
Skis, snowboards, or snowshoes make traveling on snow, especially downhill, much more fun.
Bicycling, rollerblading, skateboarding (basically using anything with wheels) is very commonly considered more fun than running.
Most people who swim in cold water prefer using a wet suit rather than toughing it out.
And it's pretty fun to use a boat, surfboard, or scuba gear rather than be stuck swimming without any aids.
I don't think this argument holds water (pun intended), though, since this device is completely human-powered.
you'll wonder if it's the technology doing all the work.
We’re talking about manually propelled bikes here. The bike isn’t doing all the work, but it is pretty essential in reaching the speed and sustaining the pace.
Sure you can argue that if you strap a rocket to your bike then you aren’t doing any work, but that’s not the case in either of these examples, so what’s the purpose of going down that tangent?
It's all relative, right? Your running shoes are incredible technology. Run barefoot.
That's a fair point. My (untested) assumption would be that it would be cumbersome and weird, and I wouldn't be 'swimming'.
If I were to guess at their motivations, it might be 'what could make me go faster in the water and also be enjoyable'? I'd try it out of curiosity, sure, but I'm pretty sure it wouldn't last beyond the novelty for me.
Biking is definitely cumbersome and weird at the beginning, and it wouldn't be considered "running" by any stretch of the imagination.
A bike is just a way for runners to cheat.
You seem to assume that because this thing is faster, it must automatically be less enjoyable.
The problem in this case is that the device is doing part of the swimming for you.
I don't understand how this is different than the running-bicycling example. How does this swim for you but a bicycle doesn't run for you?
Wait until they hear about wheelchair basketball.
But if you wanted to swim fast you could just use flippers, and be much more agile.
Sure, and if you want to run fast you can just use rollerblades instead of a bicycle and be be “more agile”. So what? Doesn’t mean bikes aren’t worth anything.
If you rollerblade or bike, you're no longer running. But with this underwater bicycle they are still swimming, just more awkwardly. So this isn't a new form of transportation.
Running does make pedestrian locomotion more tolerable. Save me some money versus using electric scooters though I think electric scooters are still faster.
Fixed gear bikes are the most fun so it kinda is true of bikes.
My favorite way to swim is with those flippers - because I go fast.
Going fast doesnt mean not enjoying it.
Yep, going fast with flippers feels great.
Feels less great for all the people in the pool that you kick.
My major hassle with touches in pools is frog kick. I have zero issues with fins, on me or others.
You don't have to do it in a crowded pool.
Balancing this device must have been a good problem to solve! All I can think of is “where does the other end that stick go?”
Two propellers spin in different directions might solve it I guess
That will counter the rotational force, but not the transversal up your butt.
Maybe design a pogo-stick-like action, pushing with both legs together?
Your blow hole, clearly
I come from family of scuba divers, and the scuba divers are a perfect market for this I think - pretty rich, pretty lazy and have to cover a lot of distance underwater
My wife and I rented the double subnado things last time we were out of town diving. Seems that fits the pretty rich and lazy market much better.
And less exertion means more time underwater.
Personally I hate swimming though I kind of like being in water, moving. So I'd definitely benefit from this, if it worked etc.
It's pretty neat. I'd want to try a version with a linear motion that drives the propeller for the counterbalance reasons.
I could see this as an alternative to fins offered at snorkeling places. That would make a great test environment too.
If you live somewhere with currents, it could be good to be able to swim at all.
The nominal mode enables motion through the water at 3.6 km/h, and for speed-seekers, the SEABIKE can reach a maximum of 7.9 km/h – much faster than normal swimming speeds or even flipper-assisted swimming.
https://www.nauticexpo.com/prod/seabike/product-68606-564117...
Pretty fast, but "superhuman"? For short distances Michael Phelps can swim faster :)
Traveling at that speed for a long distance would be beyond human capabilities, wouldn't it?
Super just means beyond, not way beyond. I blame Superman for this notion.
Not really. Most serious lap swimmers can do a kilometer every 20 minutes sustainably, akin to a marathon runner's pace (Sprint pace would be 100m/minute, with 50m/minute being what you would see in the fast lane of most recreational pools). So 3.6 kph isn't all that different, maybe a little faster than average but I assume they were also using a better-than-average bicycle person when doing the test.
There real advantage here is that you can use leg muscle. Distance swimming is all about upper body muscles, with legs being the afterburners only really used for sprinting. This machine would invert that arrangement.
Not sure why you're downvoted. Five minutes for a 500 Free is a pretty typical time for boys on highschool swim teams.
It has been a while since I was a competitive swimmer (AAA+) but imho five minutes is a very good time for 500m. That would be faster than 95% of master swimmers at such distances, and well into the 0.01% of humans overall.
Ah shit your right, I had in mind 500 (yard) Free. 500 meters in under five is very good, but still attainable by the upper tier of highschool swimmers I think. I could reliably do 500 yards in under five and was a "B relay" tier on my team.
A couple things. 500m is not actually an event. The event is 400 meters, which is roughly 500 yards. And a yard pool will only be 25 yards, not 50. So yard times are "short course" and not really valid for serious competition. A 25-meter/yard pool has fewer turns making them faster, much faster in breaststroke. And a 500-yard in a 250meter pool will include one extra lap, one extra turn, than a 400m in a 25-meter pool. Short-course/yard times all seem faster than they really should be, regardless of distance conversions.
This isn't a topic I know about, but wouldn't a 25-meter pool have more turns? But if that's a typo I can't see why stopping and turning would be a good thing?
Meters are longer than yards, by about 8%. So 500yards is loosely about the same distance as 400 meters. But 500yards divides into ten 50-yards laps, or 20 lengths of the pool. With the dive and the finish, that is 19 turns. At each turn they push off the wall and for a few seconds move much faster than when swimming in open water and a greater percentage of time underwater (which is faster). And the swimmers center of gravity doesn't get as close to the wall during a turn, effectively shortening the distance actually swam on every lap ending in a turn. But a 400-meter race in a 25-meter pool (roughly the same distance as 500 yards) has only 8 laps or 16-lengths. It has only 15 turns, meaning four fewer accelerations off the wall and less time underwater. All of these effects change based on the stroke, speed and even size of the swimmers. So there is no good direct comparison between yard and meter pools.
And then an olympic pool is 50 meters long, meaning far fewer turns for a given distance. So "long course" times are generally slower than short course even at the same distance.
(Underwater is so much faster that swimming has rules about how far you can travel underwater during each length.)
The almost-meter Yard has got to pack its bags and go home soon. What is it even doing at this point other than causing naked numeral confusion.
A lot (most?) of American school pools are built to the yard, so it's going to stick around for a long time I'm afraid.
My youthful swimming career was done in a 33+1/3rd metre swimming pool. I haven't found another one that length.
Perhaps the question must be then is Michael Phelps (or whoever) faster on it?
If he or someone else breaks the record with it, he's going beyond human level speed. Until then this may only have the potential to do so.
I imagine the first bikes were slower than the top runners of the time? I see potential for the idea.
> is Michael Phelps (or whoever) faster on it?
Nope. He would be horrible with this device. That would be like asking a champion sprinter to compete in a wheelchair race. He would be using totally different muscles, legs rather than arms, and get schooled by most everyone with a longer history. A champion bicycle rider would do better on this contraption than any champion swimmer.
(Due to water's density, champion speed swimming is also 80% technique and body shape rather than muscle/cardio. So until the technique is developed, nobody would be "good" with this thing.)
TBH I think Michael Phelps would do just fine with this. :D
A mid tier marathon runner can do a mile every 20 mins, not a kilometer. It’s a significant difference.
I meant the effort required for the pace, not the literal speed. For a skilled swimmer, 20min per km can be maintained for a few hours, like a runner maintains marathon pace for a few hours.
This is besides the point but a 20 minute mile is a typical walking pace, not anywhere near a mid tier marathon pace (regardless of the definition of mid tier). That would be an 8:40 marathon.
For short distances Usain Bolt can run faster than most people can cycle.
For very, very short distances I can run faster than most people can cycle.
For mere fractions of a second, I can outwalk a jet.
Actually I think you are making a slightly different observation about acceleration. We were talking about top-end speed, not acceleration from a standstill.
Well that's easy, jets can't walk.
Michael Phelps is an alien..
Incorrect, he is an evolved dolphin.
So dolphins are aliens??
Thanks for all the fish!
Imagine how fast Phelps could swim with this!
Given that he optimized his training for swimming and not cycling I think he might do better with fins. His top speed of 7.2 - 9.6 km/h is freestyling without fins. He reached somewhere around 13 km/h using a Lunocet monofin.
Main difference is recruiting much larger muscles, so at some point most humans will be faster over a longer period with the widget. Let Phelps train with this for a couple months and he'd be faster. Although probably sad, because he likes swimming.
At first glance, the idea of clip-ons in the water seems quite dangerous.
Really, why? Because you might drown?
Try holding your breath and just floating, arms at your side and legs not moving. You will bob to the surface. Then quickly release your breath and snap your neck back to take a new one. Repeat. That's all it takes to not drown. You could almost do it as a quadriplegic (though I'm not 100% on "water balance" in that case).
Some people (myself included) don’t float like this. I try basically every time I get in the water and my legs drift down to just after 45 degrees and then I slip under completely and don’t resurface until I give in and swim back up.
People who can float never believe me, but enough have now seen me in the water that I know I’m not “doing it wrong” I just don’t float.
The people who’ve seen me try it in water always say something along the lines of “huh, I thought everyone could float” we’ve done a few goes.
Most people float, I’m just not one of them.
Have you tried filling your lungs with as much air as possible?
This is the answer. You're supposed to learn this if you take quality swim lessons.
I was a Red Cross Water Safety Instructor and lifeguard. I taught plenty of lessons to sub-10% body fat adults who had this problem. I generally have this problem too.
I can still float all day effortlessly.
I would totally try this toy out if it was at a resort and I could try it free or for a small charge. I think I wouldn't likely buy one but I would definitely enjoy trying it.
It is extremely clear to me this is a toy for expert swimmers. Anyone who has any fear at all of it should not try it. A lot of the comments read to me as people who are not good swimmers and aren't being straightforward about it and are projecting things onto the device.
But I also see no reason why you can't use this thing with a PFD. For something like a snorkeling program you could let people use it with a PFD.
A lot of people who can't swim freak out and have poor control of their breath. That's why this is a sticking point in lessons sometimes. You can tell someone to slow their breathing and hold more air in their lungs, but they are basically freaking out breathing fast and they have no control.
This is the answer.
Nope. Not even close. If you have any other pearls than "fill your lungs" then let me know. I'll be happy to try next time I'm in the pool.
Not OP but I have the same or similar issue.
Filling your lungs is pretty easy to try and pretty much the first thing that comes to mind and almost always the first suggestion everyone gives.
I've done a lot of lap swimming, sub 30s 50m, can hold breath for ages, swim 50m underwater, comfortable scuba diving etc but that doesn't help.
The issue is not total flotation per se. It is balance. I can't push air down into my legs, so they go down. I have then lost a lot of surface tension with my body area, so I go down.
I end up vertical but with max capacity lungs I can bob near surface. But breathing out to breathe fresh air in makes me go down. Compared to someone floating happily on their back it is not relaxing.
I really wish people would give up on the "eVeRy0ne cAn f1oAt!" idea. With just my body(IE no floating aids/neoprene), nope.
What I do instead, I kick gently. Just enough to keep my feet up. That keeps the rest of me up holding surface tension. I'm pretty sure I could do this for hours if need be but never want to be in a position for survival to know.
You are not alone!
I was in swim lessons since I was like 3, on swim teams from age 8 to 18, I love the water. But I never cracked the code of floating.
I can _sort of_ float on my stomach, but this is not especially useful. And I definitely have some degree of buoyancy, I have to let out air if I want to sink to the bottom. But my default state in the water is to bob uselessly near the surface. Even with a big breath, even if I try to hold them up, my legs drag me down.
Same here. I can almost float when equipped with a 3mm closed-cell shorty wetsuit (very buoyant), but my legs still pull me vertical...
Does no part of your body stay on the surface?
On average, people stop floating around 10-15% body fat, but this varies based on lung capacity and bone size.
Lung capacity is often an under appreciated factor
Inflated Lung density is about 25% relative to water, fat is 95%, organs are around 105%, and bones are about 185%
It's just math. If you are too lean and muscular, your density is much higher than if you have a higher body fat composition, but there's also an element for non-fat people and adults that they need to 1) hold their lungs more full than normal with diaphragmatic breathing, holding the breath in for longer, and exhaling more shallowly than a full exhale that they can apply, as well as 2) leaning back much farther and tilting your head back much more than you'd expect to have to. Legs sinking is a classic problem for swimmers that occurs due to body alignment issues and especially not leaning your head and neck far enough back.
You need to be an outlier to not be able to overcome a body composition / density problem with techniques #1 and #2 above though, without observing you no one can really say if you're applying those techniques properly.
This is not true if your feet are clipped to an object heavy enough to keep you under the water though
This device is buoyant, according to the article
Which will make your feet float, driving your head underwater.
No, not all people are buoyant. Some people sink. I used to be able to float even with my lungs empty, but after losing 30kg I can now walk on the bottom of the pool will my lungs full of air.
Also, even if you are buoyant, it does not follow that being strapped to some device means you can't drown.
Can you elaborate on that?
clip-ons lock your feet to the device. If you find yourself needing to suddenly swim away from the device for any reason, you better hope that you can easily clip out. On a bicycle, you can do this fairly easily because you're on ground with gravity. In water, it could be much more challenging to clip out.
If you find yourself needing to suddenly swim away from the device for any reason
Can you elaborate on that part?
You would set the cleat retention tension lower than for a bicycle. (But also this product is ridiculous, no one is actually using it.)
Especially clipping your feet to a bouyant device!
Better than clipping them to a non-buoyant device. Or worse, the classic cement overshoes.
If it's non-buoyant and not very heavy, it's easier to control and stay afloat than if it pushes your feet upwards to the surface.
I noticed that too. Clipless pedals seem like they could be kind of stressful for someone not used to them. Or even someone who is, but is using them in a very unfamiliar situation.
What's the advantage of this over foot fins?
I can think of a huge one.
I live near a fairly dangerous ocean in SF where I’ve gone bodyboarding with a wetsuit and fins. I’m concerned that, if caught in a current, fins are not enough to propel me out of it.
This would. The extra power and ease of propulsion could make all the difference.
You just need to get familiar with the correct way to handle a current like that. It’s not to fight it.
Especially with a bodyboard and fins doing the right thing does not require a ton of strength and shouldn’t be stressful.
Your comment kind of implies that a strong swimmer with a surfboard and the right knowledge will pretty much never be in a situation where a riptide/undertow/current/whatever you call it carries them out too far to swim back. Is that true? (It might be, I just know very little about surfing)
With heavy caveats it's mostly true.
Well informed local ocean | river mouth swimmers are gemnerally aware of the currents and tend to know how far out they carry and where one can get to the side to make their way back.
That said, currents are strong, people have bad days, they can panic, water can be cold .. far colder further out than might be expected and that can weaken the body.
Surfing is a whole other ball of wax; dedicated surf spots might be well offshore and require a boat or a jet ski to even reach, if those get crunched by a slab or fail there might be a whole lot of swimming to get back to shore, assumming the surf didn't get you.
eg: The Right in Western Australia.
Didn't look to go much faster in the video than what I can do with my freediving fins.
I guess the logistics of the thing make all the difference here. Is this something you can detach from a surfboard and equip while being carried out in choppy waters? Could be either really useful or useless depending on that answer
I think it uses much stronger muscle groups.
Maybe the muscle movements are more natural and comfortable. Swimming with high power foot fins is probably as fast as this, but it gets very tiring real fast.
Tiring is good though, it means you can reach a maximum of energy expenditure. There’s a trade off with how big to make the fins though, similar to gears on a bike. Too small and you get bigger losses, I assume.
Also depends a lot what you optimize for. For underwater swimming, especially scuba, you want to optimize for saving air, meaning minimize the total energy expenditure and keeping heart rate low (the mammalian dive reflex helps here too). In water, that means moving very slowly and with longer strokes, for the same reason container ships move slowly to conserve fuel. It looks really inefficient to pedal fast because all that water around your knees needs to be pushed back and forth for no gain.
It's slower, more expensive and less accessible than a monofin
This jigger, according to the manufacturers, makes you handily quicker than an equivalent swimmer with fins on.
From the videos, not much IMO. Presumably the guys doing it in the videos have a fair amount of experience with it, and it looks... awkward.
Flippers have a great deal of fine control in all axis, and this doesn't look like it does. I'm a pretty fair diver, but when you see guys who dive all the time, they look like they were born with those flippers.
And free divers? I can't imagine them giving up their fins. They take advantage of the really long and strong muscles in the legs.
I wish we could find a good way to bike over the surface of the water. I haven’t seen anything that’s not slow and cumbersome.
Anything you choose will be cumbersome because you can't create friction on the water (well...), your ability to move is based on your ability to move water around you.
There are solutions that leverage a pair of catamarans and a track system, or a prop. These tend to move very slowly, much slower than a canoe or kayak. The water wheel style systems seem to move faster, but you can just get a pedal kayak and will be the fastest human powered craft on the water.
I've always wondered why nobody has created something that looks like a catamaran with two rowing shells and a road bike on top directly connected to a prop. That would have minimal drag, an optimal body positioning for using leg muscle strength, and would be fun and intuitive to pilot (facing forwards, feels like biking, etc). The obvious downside is that height above water may be an issue so the catamaran would have to be wide, but it seems solvable.
I believe an ocean crossing was even done with this kind of vehicle.
They have, they're still quite slow.
Foil boards are getting semi-popular for kiteboarding. They can be self-powered as well using a jumping motion. They also make e-foils with small electric props.
That's battery powered though, and looks pretty heavy. I think I'd sooner go for one of these https://liftfoils.com/
I can only imagine this is slow and cumbersome, but I love the idea of it working with your existing bike: https://www.shuttlebike.com/en/
Would this device be even better if it has the newer efficient propeller design called MX-1 Sharrow Propeller ?
https://www.boatus.com/expert-advice/expert-advice-archive/2...
At the 2020 Miami International Boat Show, Philadelphia-based Sharrow Marine introduced the culmination of a seven-year research and development project called the MX-1 Sharrow Propeller. Unlike every prop that's come before it, rather than blades, the MX-1 has loops of metal attached to the hub.
How does this change the dynamic? In a nutshell, much of a prop's inefficiency can be blamed on the blade tips, where vortices and cavitation (commonly called tip vortex cavitation, or TVC) form, creating turbulence and sapping efficiency. Simply put, the loops on a Sharrow have no tips. The net result is an efficiency gain of between 9% and 15%. But just as important, eliminating the cavitation vastly reduces vibrations and noise and makes for a smoother, quieter boat ride.
Company president Greg Sharrow tells us that the development of the MX-1 can be credited to music videos.
"I was trying to solve the problem of reducing unwanted noise from drones while filming live music productions," he says. "I've always thought it would be cool to use a drone to get cameras closer to subjects and film them from onstage, but you can't use drones for music broadcasts because they're too noisy. I knew that most of the noise comes from the blade tips and is caused, in part, by tip vortices. So, I'd have to find a way to eliminate them."
Would it be a good idea to try on wind turbines?
Utility scale wind turbines are already about 50% efficient which is close to the theoretical limit of 59% (Betz limit). The loopy blades would be more expensive to manufacture and transport so there's a trade-off and it's not obvious that efficiency would win.
I think for water, what you really want is to _breed_ cavitation, but in a way where the jets created by bubble collapse are arranged to face opposite your desired direction of motion. Kind of like Astrophage.
Is that a press release?
keep an eye on https://www.youtube.com/@rctestflight - they are doing 3d printed prop benchmark/competition and he already tested design you mentioned
Good question! Boat motors spin a lot faster than the "Underwater bicycle" propeller would so perhaps it's not as beneficial here, but would be interesting to try.
If it’s powered exclusively by a human then whatever the results, they’re not “superhuman”.
with my bike I can easily outrun any 100m dasher on the earth.
Actually you probably can’t, assuming you aren’t a world champion cyclist and you’re starting from a standstill. 100m is too short to capture the advantage unless you’re very, very fast.
See: https://www.outsideonline.com/uncategorized/who-would-win-10...
Sure… and, notwithstanding the apples to oranges comparison — since I can outswim or out stair climb you when you’re on a bike any day of the week — that means you’re demonstrating how fast a human can turn a crank that a human has connected to a wheel that a human has realized will transfer traction into forward momentum; nothing remotely superhuman has occurred, your maximum speed with that implement is still entirely limited by your very normal human capabilities.
Super == above, over, beyond.
If it augments the human's capabilities, it's definitely super!
Super, sure, superhuman, no… someone running in shoes isn’t superhuman compared to someone in bare feet, anymore than someone using a block and tackle to lift or a wheelbarrow to transport is engaging in superhuman acts just because they’ve used their very human brain to leverage a simple machine.
Something like this expands the envelope of what is, definitionally, the realm of natural human capacity… it pushes what qualifies as superhuman further away, but it doesn’t mean you’ve done something superhuman.
Cool. More like an underwater 'monocycle', though. Make it into a full body struct in Y shape acting as kind of both 'guidon' and secondary propulsion axis -- more blades, an underwater tricycle. :)
Is a Monocycle something different to a Unicycle?
Apparently! I did not expect such a nice find after asking search engine this:
https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=1700041
There are two main types of single-wheeled vehicles. In a unicycle, the rider sits above the wheel. These vehicles are recognizable by most people. Less well known is the monocycle, where the rider sits inside the wheel.
yeah likewise the dicycle has two big wheels side by side haha
The famous South Park episode was a monocycle!
You must have missed this: https://news.ycombinator.com/item?id=40080406
"Seabike says the prop turns slowly enough that you can safely use it at the local pool"
Felt a bit iffy about this claim. But looking at the research it seems cadence lowers normally when cycling under water.[0] Fun device. I wonder which pedals would be best for barefoot riding(?). Maybe those strapped ones fix riders like to use.
Yeah I wouldn't want to get hit in the face by those props at the pool. Accidents can always happen.
Flip turns would be clumsy at best.
Reverse all thrusters!
Good luck, many pools already ban fins (unless it's part of a training school, in which case the lanes are marked as such) due to risk potential.
Secondly, I could see this being used recreationally in the ocean, but in the local pool?!?
There was Australian underwater breathing device, which used your leg movement as only powersource. As I recall it could do 5 meters.
Very splendid, except some dozen people managed to misuse it. Diving deeper and without small emergency bottle.
So it was banned for all eternity everywhere. Even Chinese have not rekindled this product.
Kangaroos! Tragatschnig is Austrian, not Australian.
Original version was in 1988. I was bicycling Australia at the time and saw it on TV.
Could have been Austrian invention anyways, perhaps?
For those like me who are curious what it looks like: https://www.designboom.com/technology/exolung-underwater-air...
The idea of using transparent container maybe a good idea. Some indicator when you are sucking only water.
Because I am fool, I tried to make my own. But gave up because breakages were indicated only by lung full of water, which tend to be fatal.
There are a bunch of small watercraft I really want to try. It’s hard to justify the expensive.
The hydrofoil board with a prop and motor looks really cool.
Just not sure what the learning curve is like and kind of worried about hitting something and flying off.
Those e-foil look amazing, but the prices on them are insane. Like multiple times the price of an e-bike.
I, frankly, don’t understand it. They aren’t particularly advanced devices.
I spent a bit of time looking into building your own - from a parts point of view (buying new) you are still looking at £1000 to more like £2500 worth of batteries, controllers, motor and prop, plus the foil and the board you attach it all to. Then you need to make, seal it and make it 'sea worthy' - would be hundreds of hours of work for me.
I'd happily buy a well made new one for £3000 if that was what they cost, but half that price is a new good solid paddle board - so I can see why you can't get the same plus all the electronics you need for £3k.
We can hope in time the costs come down, but as a niche sport, it will be some time, if ever. Have you seen the cost (and service intervals!) of a new jet ski? All simple tech, but they don't come cheap and need a lot of looking after.
I can still dream though.
They're a toy being sold in small numbers to people who live near lakes or can fit driving to the lake with it into their life easily enough to want to buy it - good proxy for having a bit of disposable income to throw around. Market can bear a high price, not enough volume to make competition appealing => ££££
There's a DIY forum for building those[1] but I think tow boogies[2] are more practical as a project. The idea is a battery box, controller, and motor on a boogie board and shifting the weight of the person being towed allows for steering.
[1] https://foil.zone/ [2] https://www.youtube.com/watch?v=S9z6BP8Y42U
Since the original article is about human power, I'll also link to this foil[3] which is for pump foiling long distance. I had run across the channel well before that and thought his goal for a half hour was goofy when people were getting 90s or 2 minutes so I was quite shocked when it actually got built.
Motorized propellers have existed for 20+ years and are routinely used in spearfishing. What the heck is the news!? https://www.amazon.com/Nautica-Skipper-Seascooter/dp/B0BLP9Z...
I’ve always wished those were slightly cheaper and slightly faster.
4mph and under $250 and I’m sold!
I assume that now that we're in the world of hyper-cheap batteries I'm sure we'll see somebody do that soon enough.
What about non-motorised propellers?
From the looks of the scuba diving video, it looks worse. There's way more leg movement and it looks less controlled (and more likely to damage corals/kick up sand from the bottom) than slow finning.
Given the number of times I've been kicked in the face by another person's fins while scuba diving, I wouldn't want to be anywhere near someone using one of these.
Looks fun until both your regs are wrapped around the prop six times.
I'm inclined to agree with you.
That said this certainly has its place. There are lots of use cases for wanting to swim more quickly through the water, where precise control is less important and where you aren't right next to fragile life.
I'm curious how this compares to using fins. Just at a glance, I suspect it causes more drag and is more cumbersome to swim with. But the big thing is if it's more efficient overall than fins.
Looks a more uncomfortable than the fins (especially the lumbar lordosis part) but I imagine this should be way faster than fins.
This jigger, according to the manufacturers, makes you handily quicker than an equivalent swimmer with fins on.
Id imagine this uses stronger muscle groups. Think about how much force you can make pushing down with your leg, compared to moving it forward or backwards when you are upright.
How long till this is fitted with a motor, an e-propeller :)
There’s already plenty of electric underwater scooters on the market. This is novel because it’s not electric.
True! I realised this a while after I wrote the comment, d'oh!
This can be another transportation option, like walking and biking infrastructure. Cities like Venice can offer this today. Other cities which will be underwater eventually will get this water infrastructure built for free.
Human-powered flying cars are next. Peter Thiel will invest billions.
Pairing this with some sort of foil board contraption would be interesting. Once you get up and out of the water on a foil, it's a lot less effort.
Ah, you mean these: https://manta5.com
Yeah, it exists.
Bingo!
French company Seabike
They have a .fr domain and a showroom in Cannes, France but the company is headquarted in Italy:
PARITET SRL, Via Giovanni da Cermenate 3, 22063 Cantù (CO) Italy
The whole thing does not inspire a lot of confidence. Is the product real?
What, you don't like to travel bright?
That's a really odd mistranslation, given the Italian words for lightweight and light source are as different as in french (leggero/a vs luce). Looks like it was translated directly from the English content.
Seems prime for attaching to a surfboard
I was thinking freediving as it requires less energy than flippers though I’m not sure the decreased maneuverability of having the thing attached to you would detract from what you are wanting to do when freediving. The article does say you can dive with it, though the devil is in the details eg how easy is it to turn around? I suspice it’s not nearly as easy as flippers
Another interesting use case would be just tossing one of these into a boat that you own, or a kayak or whatever. Basically extra insurance to get you back in case your motor dies or you get swept out, similar use case as the surfboard
This device is US$310. Good carbon fins (the long ones for freediving) cost just a tiny bit more [1] and can also propel you at a superhuman speed. Plastic ones are even cheaper.
A speed comparison would have been nice. EDIT: it's already there: "This jigger, according to the manufacturers, makes you handily quicker than an equivalent swimmer with fins on."
[1] https://www.westmarine.com/mares-razor-carbon-dive-fins-41-1...
And this device is made as cheaply as possible. Plastic everywhere, holes for adaptability... And it's supposed to be used in sea water.
I guess the actual plan is to sell classes by taking advantage of the novelty effect.
on a bike, we don't use hands to propell ourselves for obvious reason, why they don't also put a crank for the hands too? it double its speed and you can counter balance the legs motion too.
Probably attitude control. If your hands are connected to the machine, you've got no control surfaces left.
The male could also use this to improve dispersion of milt over the roe laid by the female.
Please send a message to the manufacturer asking for a free product sample to try this out on a public beach.
Why wasn't this device invented 100 years ago? It's like a bicycle for people who need to swim to get around.
Hey now, it's clearly a unicycle.
I wonder how monofins compare as "swimming" method, similar, slower or faster? https://www.youtube.com/watch?v=pBsjtSjQEjM
It certainly has lower energy losses than this geared setup.
How should one take a turn in a swimming pool with this?
Avec difficulte'!
Design engineer: "Turns? Turns?!"
I still am puzzled about the logistics of it, at the very end of the video there's a sharp pointy end towards the user... do the user shove their private parts between the two shafts...
It plugs into a contraption that goes around your waste: https://www.instagram.com/reel/C6RVpqLpLjl/?igsh=MzRlODBiNWF...
I mean swim fins also propel swimmers at superhuman speeds (aside, it would be really cool if there was a proper competitive community for stuff like that, like how on land we have races for runners and races for cyclists; edit: Google informs me the competitive sport has world championships and is called "finswimming"). Is there any quantitative comparison between this doodad and fins?
It doesn't even have convenience going for it since you have to strap into it, so it's probably almost as much of a ball-ache to put on as fins, plus the awkward problem that it's hard to stand up.
If they can make it work without the waist strap (or have super-quick disconnect for that strap) I could see that convenience being nice, but still, I'd like proper comparison with fins.
Finswimming appears to be a bit faster according to the 7.9km/h figure they give, and I think using a snorkel and not your arms would make the use of this thing quite more comfortable
Imagine a pro cycler with one of these
2/3 of a triathlon.
Great for special forces, I guess.
'Underwater bicycle' propels swimmers forward at superhuman speed
so... like a normal bicycle then.
Looks like a shark cutting through the water, incredibly smooth and fast!
The real question here is about efficiency, not speed. If this does in fact propel divers more efficiently than traditional fins, it could be something useful in extending dive times without the battery limitations of a sea scooter. Otherwise it's just a gimmick.
The rotors should be placed in some fine mesh cage. I don't care what the manufacturer says, some idiot is going to cause an accident if safety isn't improved.
I'd give it a try, but the "crotch rod" mounting strategy looks awfully uncomfortable.
Engineering students have been building "underwater bicycles" for human-powered submarine competitions for decades!
I've been looking at propulsion options for my sailing dinghy. Electric is heavy, expensive and I'd like to be able to capsize at will. Something like Hobie's mirage drive would be cool but it's another hole in the hull. I also saw a hand cranked propeller with a 3:1 ratio but that would make steering with the other hand awkward. I think I'll have to stick to oars for now
Ever see a fishing lure called a "spinner"?
In the ocean this could attract some very sizable predators . . .
Now just need a way to keep your head out of the water besides turning to the sides
For those wondering... the tip hooks onto a belt... I had the same reaction.
They definitely could make it a lot more clear in the images.
They have plenty of demo videos on their channel dating as far back as 6 years
Cool invention, kinda like the foil though seems a little ridiculous.
Is it really faster than flippers? Didn't seem that quick in the video.
They should also sell a model that includes a pair of fake feet that sort of kick at the surface to complete the illusion that you’re a freak of nature.
Looks like you could use it to go in reverse, which I sometimes want while scuba diving.
Operator skill level aside, how does this compare to the fish kick?
Holy shit.
What is apparent when you learn to try to swim is that the largest muscles in our body are rendered hugely irrelevant. I don't have exact number, but I'd guess at least 95% of potential power output of our running-optimized evolutionary muscular-skeletal design is wasted in swimming.
Maybe Phelps and others can beat that with decades of training from an early age, body shape advantages, long feet, and superior flexibility, but I'd guess they buy just 10% more advantage in power-> speed conversion from the legs.
Other examples are how much faster you can swim with flippers. I would actually like to see good swimmers who train to use full scuba flippers vs good swimmers with this bike contraption.
This is hilariously efficient compared to that.
Interesting that the CIA conclusion for a device very similar to the article is "Not recommended for operational use due to its discomfort and very slight gain in speed over that of a swimmer equipped with fins."
Yeah I think for most uses I would still prefer fins for their agility. Cool idea though, and we probably haven't seen peak efficiency here.
Peak efficiency probably looks like this:
https://newatlas.com/marine/jetcycle-hydrofoil-pedal-bike/
That looks absolutely amazing. Super cool that you can maintain elevation at less than 6 MPH — I was expecting it to be closer to 10 or 15 MPH.
6mph is nothing to sneeze at on the water, in terms of the power it takes to sustain that kind of speed.
A person paddling can't sustain 6mph for very long, if they get there at all.
Sure, but a person paddling isn't hydrofoiling, right? They're using their arms instead of legs and contending with tons of additional friction/drag. I see this as being akin to bicycling, since it uses the same muscles.
Here's what I am getting at...
https://youtu.be/SDX3Hz2gsas
A guy on one of these doing the minimum speed. He doesn't look like he's casually pedaling, no?
It's probably harder to maintain 6mph than you might think.
Eh, it's hard to tell power output from pedaling cadence unless it's a fixed gear ratio. Most people pedal between 70-100 rpm regardless of the watts they're producing.
There are some clues in their body language. they appear to be straining. And the pedal movement looks a little jerky, as if the load is changing dynamically in relation to the effective flywheel/inertia of the system. Spinning a higher speeds with less torque is supposedly less tiring. So they might want to gear this down a bit and include a larger flywheel/inertia. Very impressive device tho. Maybe a hybrid approach with a solar panel for charging on the beach...
To me it doesn't look like it they were struggling with the physical exertion, but it does seem like they are struggling to properly hold on to the boat. It looks like the boat suffers from poor ergonomics, and needs some proper handles for holding on and steering.
With any wing, the faster you go in level flight the less drag is caused by lift. This strange fact is because moving a large amount of fluid slowly is more efficient than moving a small amount of fluid fast, and a faster wing can interact with more fluid mass per second ("m dot").
https://en.wikipedia.org/wiki/Lift-induced_drag#Calculation_...
Since skin drag increases with speed, adding these two drag curves together forms a 'valley' in the overall speed-vs-drag curve. Going slower or faster than this ideal speed will result in increased energy per mile.
The math is better explained in David MacKay's brilliant ebook, 'Sustainable Energy Without the Hot Air.'
https://www.withouthotair.com/cC/page_269.shtml
They seem to be struggling a bit and the there's no wind or waves. Maybe coupled with a battery like an ebike it might be sustainable for longer than a few minutes.
It depends what they're paddling in. Long, slim racing kayak - easy. Short whitewater kayak - impossible.
6 mph is a gentle paddle in a rowing shell, albeit using an additional set of muscles.
World record for a human powered hydrofoil is 21.3 mph. https://en.wikipedia.org/wiki/Decavitator 6mph looks a lot more reasonable in that context.
Looks like pretty hard work compared to land bikes. You never get to coast downhill. I wonder if you can get it to surf on waves.
Nice - yeah that looks more optimal to me.
30x the cost though...
Especially in the water I neither want the burden of being attached to something nor the burden of retrieving it.
probably should read "trained swimmer with fins"
It can take some time to get used to fins and the motions needed. Many more people have ridden a bike
Training isnt a problem for government run operations which is their context
Yes, but it's not my context.
Context of the reply thread…
... which was itself in the context of a device for civilians. To avoid litigating the primacy of nested contexts in a casual conversation, maybe let's agree to not be so picky about which caveats are on topic?
A reply is always in the context of the thing that is being replied on. It’s how replies work…
If there is an article about berries and you say you love blueberries and I reply saying “I hate them”, it in the context of blueberries. It doesn’t mean I hate all berries. And I shouldn’t have to clarify that, since I’m replying to a comment about blueberries.
How else could this work?
And everything is always in exactly one easily defined context, right? So for a comment reply we already know the full context just by looking at its immediate parent. That's how nested replies work, right?
Yes..?
Really? Go into the next HN thread and see how many deeply nested comments you can make sense of by looking only at their parent.
You are not doing HN right if you are only reading the parent
Yeah, you both seem to agree. The larger context matters.
Using fins is extremely intuitive for anyone who has swum before.
Toss a battery on it though and what does it look like then? Perhaps you're able to augment a human's ability to traverse longer distances more quickly. That's tech that didn't really exist back then!
And it would probably do a decent job of cutting you or your friends up when human and the propellor come into contact...
The article says they move slow enough to not be dangerous. That could be true even battery powered.
They already have those, seabobs
There's tens of different companies that make these from about $300
https://scootermotion.com/shop/seascooters/
Sea scooters already exist. They pull not push from what I see. Basically they’re EDFs with a place to hold on.
"Wartime paddleboards" is not a phrase I ever expected to read.
Brings a new meaning to "Charlie don't surf". At this point though, you have to pretty much imagine that the military has researched any and every mode/method/means of achieving the goals of a mission. I'm sure roller blades and skateboards have been considered at some point as well.
Not sure about the military, but French police has been using rollerblades to patrol the streets of Paris.
Taliban rollerbladers:
https://nypost.com/2023/11/15/news/taliban-seen-patrolling-k...
My memory is fuzzy but I think the Australian SAS or SBS made raids on the Japanese using paddle boards in the Second World War.
It’s described in the H I Sutton book, from the website above, but I think it’s out of print now
H. L. Hunley (submarine)
https://en.wikipedia.org/wiki/Civil_War_submarine