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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

#191
post #27

> 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 :)

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.

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

#192
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!

They already have those, seabobs

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

#193
post #155

Earlier quoted context omitted.

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.

It depends what they're paddling in. Long, slim racing kayak - easy. Short whitewater kayak - impossible.

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

#194
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."

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

#195
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!

And it would probably do a decent job of cutting you or your friends up when human and the propellor come into contact...

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

#196

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 bla…

Would it be a good idea to try on wind turbines?

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

#198

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 bla…

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.

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

#199

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 bla…

Is that a press release?

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

#200

Earlier quoted context omitted.

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.
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