Stanford Torus

[robject]

Size: 2 million tons.
Method: ACS 2000t cluster hull, with all components scaled x1000.
Habitat space: 1.4 million tons.

Kilotons Component                                BCr    Notes
-------- -----------------------------------    -----    --------------------
   2000     Cluster Hull, lifters                  40    C, lifters
    160     AV=27. 3 Kinetic Plate                  0    
     60     Fission Plant-1 (K000)                 90    1 U
     90     Gravitic Drive-1 (K000)                45    1 G
      1     Computer Model/1 std                  1.5    
     20     Life Support Long Term                 20    #10k * 40 person-months
     38     Spacious Controls                     1.2    1k cc 3k op 14k ws
    2.5     5x Crew Shared Fresher                2.5    #5,000 @ 4 crew
     24     4x Officer Suite                      1.6    #4,000 fresher + safe
     36     18x Crew Stateroom                    1.8    #18,000 @ 1 crew
     36     9x Crew Commons                         0    #9,000 t
      9     Large Cargo Lock                      1.8    
   1400     Habitat                                 0    
     40     Slow Pinnace (1000)                    15    # m1bis C
     10     Hangar Lock (1000)                      0    
    
                                              BCr 220.4

 

[Jeff M. Hopper]

I like it!

 

[whulorigan]

There is a write-up of the Stanford Torus in Cirque de Sirkas. Rhylanor Old Station is an example of one.

 

[robject]

I may be off by a large amount.

Suppose a Stanford Torus with a 1 km radius and a tube diameter of 150 m. Circumference is therefore 2 x pi x r = 6,280 m.

Tube radius is thus 75 m, and the tube cross-section is pi x r x r = 17662 m^2.

Thus the volume is roughly 6280 x 17662 = 110,917,360 m^3.

In tons, that's 8.2 million tons.

2 million-tons is too small for a Stanford Torus, says I. 8 million tons is better for a lowerbound.

I'll check out Cirque.

 

[aramis]

circumferance 2πr = π2r ≅ 3.14159 * 2000 ≅ 6283 close enough

Tube radius 75 m thus area is πr^2 = 17671.45 m^2

torus (alone) Volume is 111033049.51 m^3, or 7930932.11 Td

Not even 8 million Td. Assuming empty cargo bay freight ship density in MT or TNE (see spoiler) of about 5.68 Td per, that gives 45,061,076 tonnes...

45e9 kg or 45e12 g. suitably massive for a largish stanford torus. (about 1.2x the diameter of the Stanford's 1 mile diameter design)

Let's check the SA requirement: Stanford's paper says 670,000 m^2... if we allow 60°, that's 1/6 the circumference of the cylinder — 78.539 m wide — and the previously figured 6283 m circumference...493465 m^2. Ah, but wait... the chord of 60° adds to that by goign to (0.866 * 75) + 1000... so call it 1065m radius, and we get 525593. or so square meters of surface, and we can terrace crops and habs past ±30°...

So we have a relatively valid design there, Rob. Oh, we need to add the 4 struts at 15m diameter: 176714.6 kl each, adds another 50490 Td or so for the 4, and another 286884 tonnes...

Before we add and account for the mass of turf, people, plants, water, and other stuff.

Also, another check: LT life support is about 1500 kl/person (per T4) - which gives us about 74,000 people. Not quite a match to Stanford's 100,000, but shows (both ways) we're in the ballpark. And the T4 version includes grow-lamps and a few other essentials a torus doesn't.

Spoiler:

Type	Unladen tonnes	volume kL	density
MT Type A	1130	2700	0.419
MT Type A2	1180	2700	0.437
MT Type R	2060	5400	0.381
TNE Type A	1074.746	2800	0.384
TNE Type A2	1093.78	2800	0.391
TNE Type R	2371.59	5600	0.423
Average			0.406

0.406 * 14 kl gives 5.682 tonnes per Td.
Just doing the math in all due dilligence...

 

[atpollard]

Stanford assumed 1G because there was no long-term data on human physiology between 0G and 1G ... Traveller has lots of habitats on worlds with less than 1G so a Stanford Taurus at 0.5G could have a much smaller diameter (allowing for a much smaller station). (I am just saying that smaller is possible in Traveller).

 

[Ulsyus]

Traveller has lots of habitats on worlds with less than 1G

Isn't that because of the availability of grav plating that can set a gravity rating inside a habitat different from where it's located?