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Horizontal running inside circular walls of Moon settlements

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Re: Horizontal running inside circular walls of Moon settlements

#21

Post by Nevermark »

kyleyeats wrote: post #19
Nevermark wrote: post #12

I didn't see any mention of having a spinning surface. A tapered cylinder "gravity gym" with adjustable angled walls, and variable speed spinning, could smoothly create much greater "gravity". Spin gravity would also enable body weight exercises, core exercises, stationary or small area cardio like exercise bikes, VR games, yoga, etc. Even sleeping. EDIT: I missed this: > but Moon-based centrifuges allowing locomotio…

You know you have to fly all this stuff up there, right? You can dig out one of these pits with a shovel.

Self-sufficiency off-world is going to be much easier if people are healthy and happy.

A "gravity gym" is going to be basic healthcare. Wherever we go for the long term, we will ship and/or construct them.

Re: Horizontal running inside circular walls of Moon settlements

#22

Post by Nevermark »

fallingsquirrel wrote: post #17
Nevermark wrote: post #12

I didn't see any mention of having a spinning surface. A tapered cylinder "gravity gym" with adjustable angled walls, and variable speed spinning, could smoothly create much greater "gravity". Spin gravity would also enable body weight exercises, core exercises, stationary or small area cardio like exercise bikes, VR games, yoga, etc. Even sleeping. EDIT: I missed this: > but Moon-based centrifuges allowing locomotio…

You probably know this already, but for a while people were toying with the idea of a "childbirth centrifuge". https://patents.google.com/patent/US3216423A/en There's probably a reason it never caught on.

Reason one - We already have gravity here.

Reason two - Childbirth + vertigo? WTF!

Clearly they should have gone with a rudimentary linear accelerator such as a bungy drop or bouncing elevator type system!

Re: Horizontal running inside circular walls of Moon settlements

#23

Post by wongarsu »

hedora wrote: post #20
Nevermark wrote: post #12

I didn't see any mention of having a spinning surface. A tapered cylinder "gravity gym" with adjustable angled walls, and variable speed spinning, could smoothly create much greater "gravity". Spin gravity would also enable body weight exercises, core exercises, stationary or small area cardio like exercise bikes, VR games, yoga, etc. Even sleeping. EDIT: I missed this: > but Moon-based centrifuges allowing locomotio…

I assume they’ll eventually just build a big gravitron. The seals would be tricky (I guess the axle it spun on could contain a ladder and door?) Of course they could simply stop spinning it whenever they needed to open an airlock. (Or just put it in orbit, where these problems are easier to deal with and you don’t need to deal with day/night radiation shielding/heating.)

Spin gravity in orbit has its own issues. Most notably you can't anchor the structure anywhere, so won't spin around the spin axis you want but around its center of mass. A center of mass that will shift as people move around, equipment is moved, etc.

Another issue is that you need a certain scale, otherwise the Coriolis force as well as differential gravity (the gravity at your feet being higher than that at your head) lead to disorientation and comfort issues. The lower limit seems to be about 40 feet, incidentally the size of a typical graviton on carnival on earth. That's quite a bit wider than the typical rocket, and for now we are much more comfortable with assembling stuff in a gravity well than in orbit.

Re: Horizontal running inside circular walls of Moon settlements

#24

Post by maxerickson »

Nevermark wrote: post #21
kyleyeats wrote: post #19

Earlier quoted context omitted.

You know you have to fly all this stuff up there, right? You can dig out one of these pits with a shovel.

Self-sufficiency off-world is going to be much easier if people are healthy and happy. A "gravity gym" is going to be basic healthcare. Wherever we go for the long term, we will ship and/or construct them.

Yeah, that's what they said, a self sufficient way of constructing a gravity gym.

Re: Horizontal running inside circular walls of Moon settlements

#25

Post by irjustin »

leereeves wrote: post #2

Would running prevent deconditioning in muscles that aren't stressed by running?

In a circle, you're in an accelerating reference frame and in theory your body can't tell the difference.

The amount of exercise you would have to do to even begin to remotely keep up with earth's gravity is insane.

Separately, how does aging fair with zero g? can really old people live longer up there or is it actually worse?

Re: Horizontal running inside circular walls of Moon settlements

#28

Post by WalterBright »

wongarsu wrote: post #23
hedora wrote: post #20

Earlier quoted context omitted.

I assume they’ll eventually just build a big gravitron. The seals would be tricky (I guess the axle it spun on could contain a ladder and door?) Of course they could simply stop spinning it whenever they needed to open an airlock. (Or just put it in orbit, where these problems are easier to deal with and you don’t need to deal with day/night radiation shielding/heating.)

Spin gravity in orbit has its own issues. Most notably you can't anchor the structure anywhere, so won't spin around the spin axis you want but around its center of mass. A center of mass that will shift as people move around, equipment is moved, etc. Another issue is that you need a certain scale, otherwise the Coriolis force as well as differential gravity (the gravity at your feet being higher than that at your he…

> That's quite a bit wider than the typical rocket

You can have two habitats connected by a center tube, like an I. Rotate about the center of the I. Or a habitat and a cable connected to a counterweight.

It's not really necessary to build a wheel.

Re: Horizontal running inside circular walls of Moon settlements

#29

Post by kevin_thibedeau »

hedora wrote: post #20
Nevermark wrote: post #12

I didn't see any mention of having a spinning surface. A tapered cylinder "gravity gym" with adjustable angled walls, and variable speed spinning, could smoothly create much greater "gravity". Spin gravity would also enable body weight exercises, core exercises, stationary or small area cardio like exercise bikes, VR games, yoga, etc. Even sleeping. EDIT: I missed this: > but Moon-based centrifuges allowing locomotio…

I assume they’ll eventually just build a big gravitron. The seals would be tricky (I guess the axle it spun on could contain a ladder and door?) Of course they could simply stop spinning it whenever they needed to open an airlock. (Or just put it in orbit, where these problems are easier to deal with and you don’t need to deal with day/night radiation shielding/heating.)

Just put a centrifuge under a static dome. No seals needed.

Re: Horizontal running inside circular walls of Moon settlements

#30

Post by WalterBright »

irjustin wrote: post #25
leereeves wrote: post #2

Would running prevent deconditioning in muscles that aren't stressed by running?

In a circle, you're in an accelerating reference frame and in theory your body can't tell the difference. The amount of exercise you would have to do to even begin to remotely keep up with earth's gravity is insane. Separately, how does aging fair with zero g? can really old people live longer up there or is it actually worse?

Our bodies are exquisitely optimized for the surface of the Earth. Any deviation from that (gravity, sunlight, gas pressure, gas composition, radiation, etc.) is likely to be deleterious.

This does not bode well for expanding out into the solar system. It might only work if we do some genetic engineering to make off-world habitats more habitable.

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