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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

#111

Post by jillesvangurp »

vintermann wrote: post #97
jillesvangurp wrote: post #73

Earlier quoted context omitted.

Wild idea: build one on earth to simulate 1.1G (or higher; whatever would still be comfortable) and put gyms, hotels, swimming pool, living quarters, etc. in it. Being in it for extended periods of time would build up muscles and bones. That would likely be something that fitness people and professional athletes would be interested in. And it's a good dry run for building and operating these things on Mars and the Mo…

Spinning stuff in air takes more energy than spinning stuff in a vacuum.

But then we do operate trains in our atmosphere so this is a solvable problem. The advantage outside of our atmosphere is of course that aerodynamics don't matter, which indeed would make things more energy efficient. Also there would be no weather (or very little of it on Mars), no humidity.

Re: Horizontal running inside circular walls of Moon settlements

#112

Post by cnity »

eru wrote: post #109
gadders wrote: post #107

Earlier quoted context omitted.

Got you. So we would need to do the experiment to try resistance training in low/no gravity to see whether it would work or not. It would seem like the obvious thing to try though as it is the best method in regular gravity.

Oh, it's definitely something we should try. We need a lot more experiments. The only thing we know for sure is that moving around in 1g is generally enough for our bodies. Especially once you throw in a bit of deliberate exercise. We also already know from our space stations that 0g is bad for you, and even exercise can only mitigate some of the damage. But that's already the limit of our definite knowledge. But we…

Possibly dumb question, but if you wore weighted vests (for example) to match the same force due to gravity on earth for that individual, would that be equivalent to existing on earth without the vest? Ignoring e.g. the difference in exact distribution of the weight.

Re: Horizontal running inside circular walls of Moon settlements

#113

Post by croon »

ordu wrote: post #94
scotty79 wrote: post #89

Earlier quoted context omitted.

It's because walls are a bit too steep. If you made them into paraboloid, a per would naturally climb as high as they need to, to be able to run symmetrically.

But one leg will still be running a shorter distance then the other.

This is steaming my brain a bit. Is it not the case (assuming an "optimal" tilt of the track) that the inner leg would travel more radii each step, meaning you would travel a larger segment of the circle on every inner step than outer step, ending up with an equal gait? This is my intuition without any formulated proof.

Re: Horizontal running inside circular walls of Moon settlements

#115

Post by scotty79 »

ordu wrote: post #94
scotty79 wrote: post #89

Earlier quoted context omitted.

It's because walls are a bit too steep. If you made them into paraboloid, a per would naturally climb as high as they need to, to be able to run symmetrically.

But one leg will still be running a shorter distance then the other.

Person running would need to constantly turn a bit to one side to not climb further up the wall. So it shouldn't be much different from running in circles on flat surface.

Not sure if runners that train by running in small circles are concerned about evenness and try to run the same amount clockwise and counter clockwise to even things out.

Re: Horizontal running inside circular walls of Moon settlements

#116

Post by Nevermark »

eru wrote: post #103
Nevermark wrote: post #93

Earlier quoted context omitted.

Circular dome colony over a very large rotating space, running on concentric rings of superconducting rails. Spokes of slidable inner-outer weights to counter balance its residence’s movements. Running on reliable constant nuclear power, from a safe distance. Maximum gravity at the tilted edges. Only natural gravity at the center. Enter & exit from a tunnel that connects under the center. Aside from the challenges of…

> Being able to quickly “adjust” gravity, by moving location, will be significant. Who is doing the adjusting and the moving? I don't think you'd want to move anything large. You'd build eg your factory in the environment where it's best; and build a second factory in a different environment, instead of moving them around. However, if you eg making computer chips, you might move those around between different environ…

Yes, I meant move materials and parts between g-force specific equipment.

If entire factories needed to "move" up and down in g-forces, they should be in their own variable spin bowls! Not sure what kind of factory that would be.

Re: Horizontal running inside circular walls of Moon settlements

#117

Post by Someone »

jillesvangurp wrote: post #73
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…

Wild idea: build one on earth to simulate 1.1G (or higher; whatever would still be comfortable) and put gyms, hotels, swimming pool, living quarters, etc. in it. Being in it for extended periods of time would build up muscles and bones. That would likely be something that fitness people and professional athletes would be interested in. And it's a good dry run for building and operating these things on Mars and the Mo…

The acceleration needed to make a turn with radius r at speed v is. v²/r (https://courses.lumenlearning.com/suny-physics/chapter/6-2-c...)

If that combined that with earth’s gravity has to give you 1.1g, that has to be (via the Pythagorean theorem) about 0.2g or 2m/s². Let’s pick r = 100m. Then, v² has to be 20, giving as a velocity of about 16 km/hour. r = 1km would require about 50km/hour.

Sounds doable, until you consider your “put gyms, hotels, swimming pool, living quarters, etc. in it”. That’s a lot of mass and space.

Centrifuges that we put potential astronauts and fighter pilots in are a lot smaller.

On the other hand, there’s the idea of “a massive floating railway, Maglev-style, which will travel along a track with a radius of 2.5 kilometers within an underground vacuum tunnel. The machine will run on excess energy generated from wind and solar, and it can reach speeds up to 2,000 km/h. When the renewable energy production is insufficient, the kinetic energy from the train movement will be reconverted and sent to the grid.” that engineers claim can be built (https://www.greenoptimistic.com/energy-train-mph/). That would hit over 10g and weigh a lot more than that hotel. I can’t find updates, though.

Re: Horizontal running inside circular walls of Moon settlements

#118

Post by Nevermark »

> Moon-based centrifuges allowing locomotion inside would pose technical challenges and demand substantial electrical energy.

Comments:

> would pose technical challenges

That's a very funny disadvantage to call out! "Technical challenges" are how you know you are on the moon.

A stable rotating system would seem to be one of the simplest possible lunar challenges. If it is implemented within an existing environment shell, it could be quite low tech.

> demand substantial electrical energy.

Maintaining rotation in low Earth gravity should be a very low energy process. The only energy loss would be friction at the point of rotation, which should be minimal, and some position controlled weights, for maintaining balancing in the context of human movement.

But the proposed no-tech solution has a great return on investment, and is realistic for early days, or infrequently inhabited outposts.

Re: Horizontal running inside circular walls of Moon settlements

#119

Post by sandworm101 »

BLKNSLVR wrote: post #81
pmcarlton wrote: post #18

It takes a few clicks to get to the supplemental data movie: https://rs.figshare.com/articles/media/a_participant_running... You'd probably want to switch directions often!

The ankle flex when the right foot lands makes me wince every single time. I wonder how much that's to do with the direction of gravity, the angle of their body looking not quite horizontal (and therefore 'weirding' the angle that feet hit the ground), and how much is to do with the individual's physiology.

In actual lunar gravity the forces should balance out. At a particular speed, tied to the wall angle, the forces should align with the floor to let the foot land as if running on a horizontal surface. Imaging a motorcycle in a turn. Then tilt the road to match the bike's lean angle. The tire/foot then falls flat against the road.

Re: Horizontal running inside circular walls of Moon settlements

#120

Post by eru »

cnity wrote: post #112
eru wrote: post #109

Earlier quoted context omitted.

Oh, it's definitely something we should try. We need a lot more experiments. The only thing we know for sure is that moving around in 1g is generally enough for our bodies. Especially once you throw in a bit of deliberate exercise. We also already know from our space stations that 0g is bad for you, and even exercise can only mitigate some of the damage. But that's already the limit of our definite knowledge. But we…

Possibly dumb question, but if you wore weighted vests (for example) to match the same force due to gravity on earth for that individual, would that be equivalent to existing on earth without the vest? Ignoring e.g. the difference in exact distribution of the weight.

There are some differences, eg how your organs sit inside your body.

Perhaps your liver works best in 1g? We can make some educated guesses, but honestly we don't know! No one has run experiments.

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