Sleeping At 2g... Constant acceleration.

[Spacescifi]

If one had a fictional constant acceleration drive, would upping the acceleration for 8 hours while the crew slept be OK-ish?

 

I mean why not? Everyone but the helm control crew are sleeping on their backs anyway?

 

Then revert to 1g when they wake up.

 

Still not sure what the effects would be if done routinely. Probably not good.

 

Then again if crew is all young and healthy (no one over 45 years and must be healthy and fit) then that may be mitigated too.

[cubinator]

I sleep on my side...

If you upped the gees just a little bit, it might feel more like a weighted blanket.

There were some experiments back in the day where some people lived in high-G centrifuges for many days at a time. Presumably they found some way to sleep.

[Spacescifi]

6 minutes ago, cubinator said:

I sleep on my side...

If you upped the gees just a little bit, it might feel more like a weighted blanket.

There were some experiments back in the day where some people lived in high-G centrifuges for many days at a time. Presumably they found some way to sleep.

 

Great. So cut travel time down even more for manned scifi interplanetary flight.

I wonder what is the limit? 3g? 4g? 5g?

Obviously unmanned could go faster still... but sleeping on the back I wonder...

Edited October 2, 2021 by Spacescifi

[Gargamel]

Why would you need to have a pattern of higher thrust and lower thrust for long periods of time?  

If your ship needs to be somewhere right now, then you run high acceleration the whole time, and the crew just deals with it.  But why run it on a schedule?   Unless I'm missing something completely fundamental in the math here, why not just run slightly increased thrust for the entire time?   2g for 8hrs a day is the same as 1 1/3 g for 24 hours, no?    A healthy crew would just get a workout at the slightly increased g's. 

Secondly, why only 8 hours?   You either have an autonomous ship that doesn't require crew, or you require a constant watch.  With an autonomous ship, you could run at high thrust for 20 some hours a day, with regular breaks for the crew to arise for human needs.  Otherwise they are in their racks the rest of the time.   If you need a constant watch.... why do people think it's ok to disrespect third shift?!   We're people too ya know!

Within the Solar system, the time gained for just about any distance journey is pretty much negligible in practical terms.  6 weeks to someplace?  OK, why does it matter then if you arrive a week earlier.  It really doesn't, and as mentioned, if it does, then the crew just deals with it.  

But for interstellar travel you say!  I say it would not have nearly the impact you think it would.   Turns out... we have this speed limit, in terms of both literal speed and energy required.   At 1g constant acceleration, it takes a ship roughly a year to accelerate to the speed of light.    You then flip over and take another year to return to... whatever normal is.    So the rule of thumb, for constant 1g acceleration, is that to travel a distance of X light years, it requires X+1 years to do it, when observed from the Earth.   From the ship's point of view, the entire trip takes even less time. 

You would approach the speed of light within a short time frame at 1g, but for the next however long you are near the speed of light, you'd want to maintain that 1g acceleration to keep stuff from floating around inside the ship, but due to Mr Einstein et al, you really wouldn't gain any speed.  Basically this would be the cruise phase.   Because you'd reach this cruise phase relatively quickly in the scheme of things, there's no reason to do pulsed acceleration as you describe.  

So, for really short distances, Earth to the Moon, or even Earth to Mars let's say, there's no benefit, as the tiny amount of time saved would really not have practical benefit.   For interstellar distances, there would be no noticeable time gained, and just a whole lot of fuel wasted.   For longer interplanetary distances, the amount of time saved might be appreciable, but at what cost to the crew?  So honestly, short of tactical situations, there isn't a real reason to accelerate faster than 1g.