NSEP Posted June 6, 2018 Share Posted June 6, 2018 12 minutes ago, Mad Rocket Scientist said: I think the sickening coriolis forces would be worst than the muscle and bone strength decay. I'll take a look at the math and see how bad it would be. There is the option of only spinning up the gravity when the peeps are asleep in bed, laying flat, but that would take up fuel unless the BFS has reaction wheels of some sorts. 11 minutes ago, sevenperforce said: Also the windows would be in the floor. That would be awesome and terrifying at the same time. Quote Link to comment Share on other sites More sharing options...
Mad Rocket Scientist Posted June 6, 2018 Share Posted June 6, 2018 (edited) 52 minutes ago, Scotius said: Looking at this picture gave me an interesting idea. Crew quarters are essentially a cylinder with an empty tunnel in the center. Start rotating the BFR, and there will be artificial gravity Not much of it, sure - but i guess it could be useful on long trips. A bit of gravity is better than zero-g, right? 29 minutes ago, Mad Rocket Scientist said: I think the sickening coriolis forces would be worst than the muscle and bone strength decay. I'll take a look at the math and see how bad it would be. If you rotate a cylinder with a radius of 4.5m to provide an acceleration equal to mars surface gravity (3.71 m/s^2) on the outer edge, the cylinder needs to rotate at 3.7 rpm, or 4 m/s tangential velocity. At the height of your head if you're standing on the outer edge (2.5 m radius), the gravity would be 2.06 m/s^2, and the rotation rate would be would be 8.67. A study I found from 1977 based in a 15ft (~5 m) diameter room said that: "In brief, at 1.0 rpm even highly susceptible subjects were symptom-free, or nearly so. At 3.0 rpm subjects experienced symptoms but were not significantly handicapped. At 5.4 rpm, only subjects with low susceptibility performed well and by the second day were almost free from symptoms. At 10 rpm, however, adaptation presented a challenging but interesting problem. Even pilots without a history of air sickness did not fully adapt in a period of twelve days." However, some other studies showed a smaller acclimation time. This honestly sounds better than I thought, and I think the largest problem with this would be the way it makes use of the center of the ship much harder. However, much smaller gravities (small enough that coriolis effects are small to unnoticable), although they would be less useful in combating the effects of microgravity, might still be useful so objects can be set down and exercise machines could be simpler. 15 minutes ago, NSEP said: There is the option of only spinning up the gravity when the peeps are asleep in bed, laying flat, but that would take up fuel unless the BFS has reaction wheels of some sorts. That's an interesting idea. I wonder if that would involve sleeping in concave beds (might be bad for your spine) or flat (you'd feel like you were being gently pulled up or down from the center of the bed). Edited June 6, 2018 by Mad Rocket Scientist Quote Link to comment Share on other sites More sharing options...
HebaruSan Posted June 6, 2018 Share Posted June 6, 2018 7 minutes ago, Mad Rocket Scientist said: might still be useful so objects can be set down and exercise machines could be simpler. Or think about all the effort wasted on the perfection of the "zero g" toilet and shower. Quote Link to comment Share on other sites More sharing options...
NSEP Posted June 6, 2018 Share Posted June 6, 2018 12 minutes ago, Mad Rocket Scientist said: That's an interesting idea. I wonder if that would involve sleeping in concave beds (might be bad for your spine) or flat (you'd feel like you were being gently pulled up or down from the center of the bed). Or lay down like Y-person depicted here. X-person is going to get spine problems, Z-person is going to get a severe headache, but Y-person is just fine. Quote Link to comment Share on other sites More sharing options...
Mad Rocket Scientist Posted June 6, 2018 Share Posted June 6, 2018 4 minutes ago, NSEP said: [...] Or lay down like Y-person depicted here. X-person is going to get spine problems, Z-person is going to get a severe headache, but Y-person is just fine. Wait... Why didn't I think of that? That makes perfect sense. Quote Link to comment Share on other sites More sharing options...
NSEP Posted June 6, 2018 Share Posted June 6, 2018 2 minutes ago, Mad Rocket Scientist said: Wait... Why didn't I think of that? That makes perfect sense. Being awake way too late on a school night while listening to relaxing music can make wonders Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 6, 2018 Share Posted June 6, 2018 40 minutes ago, Mad Rocket Scientist said: If you rotate a cylinder with a radius of 4.5m to provide an acceleration equal to mars surface gravity (3.71 m/s^2) on the outer edge, the cylinder needs to rotate at 3.7 rpm, or 4 m/s tangential velocity. At 3.0 rpm subjects experienced symptoms but were not significantly handicapped. At 5.4 rpm, only subjects with low susceptibility performed well and by the second day were almost free from symptoms. At 10 rpm, however, adaptation presented a challenging but interesting problem. Even pilots without a history of air sickness did not fully adapt in a period of twelve days." However, some other studies showed a smaller acclimation time. Sustained 3 rpm acceleration might prove to cause second-order effects over time. 40 minutes ago, Mad Rocket Scientist said: This honestly sounds better than I thought, and I think the largest problem with this would be the way it makes use of the center of the ship much harder. However, much smaller gravities (small enough that coriolis effects are small to unnoticable), although they would be less useful in combating the effects of microgravity, might still be useful so objects can be set down and exercise machines could be simpler. 20-50% of Mars gravity would be enough to make mobility easy without losing your sense of up and down, and avoid stuff floating about, but avoid motion sickness. 40 minutes ago, Mad Rocket Scientist said: That's an interesting idea. I wonder if that would involve sleeping in concave beds (might be bad for your spine) or flat (you'd feel like you were being gently pulled up or down from the center of the bed). Just make the beds parallel to the axis of rotation. Quote Link to comment Share on other sites More sharing options...
DAL59 Posted June 6, 2018 Share Posted June 6, 2018 (edited) 1 hour ago, Mad Rocket Scientist said: However, much smaller gravities (small enough that coriolis effects are small to unnoticable), although they would be less useful in combating the effects of microgravity, might still be useful so objects can be set down and exercise machines could be simpler. Plus, reduces the danger of dust and food getting in your eyes, makes it easier to clean. There's no real reason they wouldn't want 1/50 gee spin. Edited June 6, 2018 by DAL59 Quote Link to comment Share on other sites More sharing options...
mikegarrison Posted June 6, 2018 Share Posted June 6, 2018 On 6/5/2018 at 11:06 AM, Ultimate Steve said: Doubled in length and width, so x4 in overall area. It's not the best improvement, but it's still a big one. IIRC they missed by <50m last time. The ship is ~200ft long with the net being half of that, so the new net will be about 400ftx400ft, or 122m*122m. If they missed the edge of the old net by 50m, then it was a total of (50m miss, old net was 61m, /2 for r is 30m) 80 meters from the center of the net, meaning to hit the net their accuracy would have to increase by 50m, preferably close to 80. However, with the new design, they only have to increase accuracy by (radius doubles, adds 30m, 50-30=) 20 meters to hit the new net, although again the preferred number is 80. I think. My math skills have already degraded significantly over the summer. Maybe they should hire that guy who jumped from an airplane into a net. Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted June 7, 2018 Share Posted June 7, 2018 Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted June 7, 2018 Share Posted June 7, 2018 Four fairing halves are outside the building that will be next to the BFR factory, presumably there due to lack of storage and future drop testing. There's $12m dollars in rocket parts, just sitting there... Quote Link to comment Share on other sites More sharing options...
Scotius Posted June 7, 2018 Share Posted June 7, 2018 Rocket parts next to a dilapidated shack Oh, it reminds me of so many old-timey SF stories... Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted June 7, 2018 Share Posted June 7, 2018 (edited) 30 minutes ago, Ultimate Steve said: Four fairing halves are outside the building that will be next to the BFR factory, presumably there due to lack of storage and future drop testing. There's $12m dollars in rocket parts, just sitting there... Fixed that for you... (just a quick hack job, I gotta go to bed. Someone can feel free to make a better version and/or tweet it at Mr Musk). Edited June 7, 2018 by StrandedonEarth Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 7, 2018 Share Posted June 7, 2018 20 minutes ago, StrandedonEarth said: omeone can feel free to make a better version and/or tweet it at Mr Musk). Done. 51 minutes ago, Ultimate Steve said: Four fairing halves are outside the building that will be next to the BFR factory, presumably there due to lack of storage and future drop testing. There's $12m dollars in rocket parts, just sitting there... Dare you to go jump the fence and scrawl your name on one. Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted June 7, 2018 Share Posted June 7, 2018 39 minutes ago, CatastrophicFailure said: Done. Dare you to go jump the fence and scrawl your name on one. Will you pay for my trip west? Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 7, 2018 Share Posted June 7, 2018 27 minutes ago, Ultimate Steve said: Will you pay for my trip west? Can't. Something about "contributing to the delinquency..." being a violation of my probation, or something like that... Quote Link to comment Share on other sites More sharing options...
Nivee~ Posted June 7, 2018 Share Posted June 7, 2018 2 hours ago, Ultimate Steve said: $12m dollars in rocket parts 3 million each... and here I thought they would be the cheapest part of a rocket...I mean yeah they got the shock dampeners and all..... but 3 million apiece? Quote Link to comment Share on other sites More sharing options...
KSK Posted June 7, 2018 Share Posted June 7, 2018 Now those are some seriously overspecced dumpsters. I mean, I know they're a rocket company and all but c'mon... Quote Link to comment Share on other sites More sharing options...
tater Posted June 7, 2018 Share Posted June 7, 2018 Wonder if I should drive around there when I'm in LA in a few weeks... Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 7, 2018 Share Posted June 7, 2018 57 minutes ago, Nivee~ said: 3 million each... and here I thought they would be the cheapest part of a rocket...I mean yeah they got the shock dampeners and all..... but 3 million apiece? They're worth twice that, new. Hence why SpaceX is spending all this fuss to try and reuse them. Quote Link to comment Share on other sites More sharing options...
Nivee~ Posted June 7, 2018 Share Posted June 7, 2018 10 minutes ago, CatastrophicFailure said: worth twice that, new Expensive rocketry business is expensive Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted June 7, 2018 Share Posted June 7, 2018 6 hours ago, CatastrophicFailure said: Done. You tweeted it? post it here please! Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted June 7, 2018 Share Posted June 7, 2018 4 hours ago, StrandedonEarth said: You tweeted it? post it here please! Promptly lost in the æther... Quote Link to comment Share on other sites More sharing options...
Wjolcz Posted June 7, 2018 Share Posted June 7, 2018 10 hours ago, tater said: Wonder if I should drive around there when I'm in LA in a few weeks... Do it! I need more pictures of anything that's happening there. Quote Link to comment Share on other sites More sharing options...
kurja Posted June 7, 2018 Share Posted June 7, 2018 19 hours ago, sevenperforce said: Sustained 3 rpm acceleration Come again? Quote Link to comment Share on other sites More sharing options...
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