The other reason Lab ships might look like that

[rinku]

I'm working my way through the Starship Operator's Manual, in the sensor section at the moment. And it just occurred to me that the old reason given for the Lab Ship being a torus hull, while valid, may actually be secondary.

Hull mounted sensors around a ring (possibly supplemented by sensors suspended on retractable internal spokes) should be an efficent use of tonnage to get a synthetic aperture sensor of a given diameter. Essentially the whole ship can be one giant virtual radio telescope dish.

I'd expect this comes up much more often for Lab Ships than delicate gravitic experiments.

Huh.

 

[CordwainerFish]

I always thought they might be a homage to the space city in Niven's essay "Bigger Than Worlds".

 

[rinku]

Could well be too. No reason it can't be all of the above.

 

[shirgall]

I thought the reason of being able to spin it in case you have experiments that don't tolerate gravitics was a good one.

 

[rinku]

My thoughts are along the line of the original designers starting with one or the other, then realising there's two advantages to the configuration (three if you include being able to jog indefinitely through the ship...)

 

[shirgall]

My thoughts are along the line of the original designers starting with one or the other, then realising there's two advantages to the configuration (three if you include being able to jog indefinitely through the ship...)

Indeed, you can run all the way around...

 

[MonsterX]

Form does not follow function. The right way to do things is to start with an iconic form, and then try and think up a function to justify it. We want our cool lab ships, whether they make sense or not!

That said, getting better triangulation opportunities for sensors does make sense. Though you could manage it more cheaply with long aerials, I suppose.

 

[CordwainerFish]

three if you include being able to jog indefinitely through the ship...

 

[Condottiere]

Infinite horizon.

Or:

 

[phavoc]

I had read somewhere that in order to avoid motion sickness you'd need about 200m radius and a revolution of about 2 RPM. Anything faster than that and the inner ear/senses get disoriented too much. The ideal was much bigger, about 900m and around 1 RPM to be minimally disorienting.

That's for 1G. Obviously if you are looking for lower G's you can adjust your rotation.

I think the diameter of the Lab ship is about 60m, or a radius of 30m - which is too small to generate the necessary 1G without causing issue to crew. Google tells me that at 2RPM you could get .13G w/o too much disorientation. With about 1 day or so acclimation you could get 4RPM and about .5G. Beyond that the average person is supposed to starting having issues.

I suppose with drugs or adequate training and acclimation time your regular crew could get used to a 6RPM rotation and you'd have 1G. That makes sense for permanent crew, or else given enough time for visitors to get used to that.

I wonder though with the engines embedded port and starboard if the continual rotation would cause challenges in headings? I suppose if you cut main thrust and used attitude thrusters to make your course change and then went back to main thrust (other than your vector) it wouldn't be an issue. Might also be able to adjust port and starboard thrust to offset any wobbles. Not sure on the math portion to determine the wobble factor.

 

[CordwainerFish]

ideal was much bigger, about 900m and around 1 RPM to be minimally disorienting.

If I recall Heppenheimer's Colonies in Space, that's what was claimed there.

(Anyone else remember that book?)

 

[Condottiere]

I backburnered the issue a couple of months ago, when I was seeing where I could cut corners in hull construction budgets.

In human terms, I felt it's more of a case of attaining the minimum gravity that has no long term health effects.

Immediate ones being nausea, which obviously you'd want to avoid.

Traveller would indicate seventy percent Terran norm, NASA forty percent.

No one probably can give a definitive answer.

 

[rinku]

Form does not follow function. The right way to do things is to start with an iconic form, and then try and think up a function to justify it. We want our cool lab ships, whether they make sense or not!

That said, getting better triangulation opportunities for sensors does make sense. Though you could manage it more cheaply with long aerials, I suppose.

You could do both. The aerials extend from the ring.

 

[To Tha Moon!]

Or...

The architect liked doughnuts.