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'Underwater bicycle' propels swimmers forward at superhuman speed

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Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#221

Post by HumblyTossed »

freeqaz wrote: post #189
pge wrote: post #93

Earlier quoted context omitted.

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."

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!

Sea scooters already exist. They pull not push from what I see. Basically they’re EDFs with a place to hold on.

Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#222

Post by flawsofar »

causal wrote: post #104
pge wrote: post #93

Earlier quoted context omitted.

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.

Especially in the water I neither want the burden of being attached to something nor the burden of retrieving it.

Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#223

Post by klabb3 »

carlosjobim wrote: post #70
BurningFrog wrote: post #19

Earlier quoted context omitted.

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.

Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#224

Post by hi-v-rocknroll »

thelastgallon wrote: post #29

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.

Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#228

Post by gnabgib »

hi-v-rocknroll wrote: post #224
thelastgallon wrote: post #29

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.

2013: https://en.wikipedia.org/wiki/Human-powered_helicopter

Re: 'Underwater bicycle' propels swimmers forward at superhuman speed

#229

Post by xarope »

tokai wrote: post #8

"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. [0] https://ieeexplore.ieee.org/abstract/document/23706

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?!?

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