Growth paths, generations and staging

How the thread thinks rotating stations should evolve, from first demonstrators to settlements.

Key results

Start small

  • "Egyptians didn't build the Great Pyramid first": build a minimum viable product mikelepage, 2018-07-11.
  • Coastal Ron's "Minimum Viable Rotating Space Station": small = sooner (mass = cost); it may lack elevators; Mars g as the lower limit Coastal Ron, 2019-03-24.
  • Twark_Main's MVP: 3 arms instead of 4 (15 vs 20 units) Twark_Main, 2023-06-10.
  • Iterate smallest steps (X-planes approach): spin the whole Dragon for 1/100–1/10 g first Paul451, 2015-09-01.
  • Coastal Ron's "Generation One" is a "minimum viable dwelling" to prove rotation speed, minimum g, distance, radiation, features and self-sufficiency, like a cruise ship with a fleet of support vessels Coastal Ron, 2018-11-01.
  • Three design classes (Coastal Ron): (1) small AG research; (2) medium Mars-g refuge in deep space; (3) large 1 g (paused, no use case) Coastal Ron, 2022-10-30.
  • First-generation metric (mikelepage): <15,000 t, <$1.5B launch, <2.5 years' assembly mikelepage, 2022-10-14.

Published roadmaps

  • Paul451, 2014–15: (1) ISS 6–12 month AG window plus a BEAM centrifuge; (2) DragonLab on an F9 second stage for 2–4 week animal experiments; (3) 12-month multigenerational animal flight; (4) human-tended facility Paul451, 2015-03-02; Paul451, 2015-11-08.
  • Paul451, 2018: DragonLab baton → BA-330 on an FH stage for a human-tended animal study → second hab → 30–40 m arms only if humans can't take >5 rpm Paul451, 2018-07-15.
  • Paul451, 2022, Starship-derived Gen 1–5. Gen 1 is a single Starship "tumbling pigeon", 4 crew, 3-month runs, returning to Earth between runs Paul451, 2022-12-31; Paul451, 2022-12-31. See Paul451's Starship generations.
  • Coastal Ron's generations: the first 100% from Earth-made components; later ones from space-fabricated parts; converting Starships into station material is uneconomic Coastal Ron, 2022-10-13; Coastal Ron, 2022-10-13.
  • JohnFornaro's assembly sequences with cap-off points: sequence 3 Mars experiment, 4 Earth experiment, 7 tourist; thrive experiments ~20 years, full build 20–40 years JohnFornaro, 2023-06-09.
  • Vast's roadmap adds spokes until the station looks like the 2001 wheel (2040s) JohnFornaro, 2023-06-10.

Growth mechanisms

Scaling arguments

  • Paul451: if humans need 1 g at 1 rpm, there would be only giant cities, no towns, and no organic growth path Paul451, 2018-07-16. This is why tolerance of higher rpm matters.
  • Why jump to km scale when a 500 m diameter satisfies even the most conservative limits (<2 rpm, <1% head/foot)? Volumes bigger than a basketball court create weather mikelepage, 2022-10-10.
  • Giant stations never come first mikelepage, 2018-11-01.
  • Design lifetime: ≥100 years, 1000 with maintenance (Roy_H); Canadian bridges are designed for 100 years; mechanisms last decades Roy_H, 2022-10-18; lamontagne, 2022-10-18. Coastal Ron: early generations are short-lived, with replaceable members Coastal Ron, 2022-10-18.

Open questions

  • Will growth come from repeated small stations (a production line) or by enlarging one station?
  • What is the first commercially justified rotating station: research, tourism, or crew health for zero-g workers?

Sources

Forum posts

  • Paul451, 2015-03-02 (reply #468): Stepwise roadmap. Post.
  • Paul451, 2015-09-01 (reply #579): Smallest steps first. Post.
  • Coastal Ron, 2015-09-13 (reply #631): Bands added indefinitely. Post.
  • Paul451, 2015-11-08 (reply #739): Roadmap (key). Post.
  • mikelepage, 2018-07-11 (reply #906): MVP; pyramid analogy. Post.
  • Paul451, 2018-07-15 (reply #935): 2018 roadmap. Post.
  • Paul451, 2018-07-16 (reply #951): No organic path at 1 rpm. Post.
  • mikelepage, 2018-11-01 (reply #1248): Fractal doubling. Post.
  • TrevorMonty, 2018-11-01 (reply #1249): Build outer rings while rotating. Post.
  • Coastal Ron, 2018-11-01 (reply #1253, 1 like): Generation One. Post.
  • lamontagne, 2019-03-12 (reply #1347, 2 likes): Dumbbell fleet. Post. Attachments: Dumbell station.jpg, Dumbell stationb.jpg.
  • Coastal Ron, 2019-03-24 (reply #1383, 3 likes): MVP station. Post.
  • mikelepage, 2022-10-10 (reply #1960, 2 likes): 500 m satisfies conservative limits. Post.
  • Coastal Ron, 2022-10-13 (reply #2039): Generations. Post.
  • Coastal Ron, 2022-10-13 (reply #2058): Later generations. Post.
  • mikelepage, 2022-10-14 (reply #2077): First-gen metric. Post.
  • Coastal Ron, 2022-10-18 (reply #2134): Early generations short-lived. Post.
  • lamontagne, 2022-10-18 (reply #2135): Bridge lifetimes. Post.
  • Roy_H, 2022-10-18 (reply #2136, 1 like): ≥100 yr design. Post.
  • Paul451, 2022-10-30 (reply #2260): Barbell grows to torus. Post.
  • Coastal Ron, 2022-10-30 (reply #2270): Three designs. Post.
  • lamontagne, 2022-11-17 (reply #2415): Extrusion shack. Post. Attachments: Extrusion construction.jpg.
  • Paul451, 2022-12-31 (reply #2736): Gen 1–5 roadmap. Post.
  • Paul451, 2022-12-31 (reply #2737): Roadmap cont.. Post.
  • lamontagne, 2023-03-07 (reply #3524): Constellations. Post.
  • lamontagne, 2023-03-07 (reply #3526): Old tori as neighbourhoods. Post.
  • Coastal Ron, 2023-03-07 (reply #3527): Widen wheel. Post.
  • JohnFornaro, 2023-06-09 (reply #3819): RS sequence III. Post. Attachments: Ring-SK-204-Assembly-Sequence-III.jpg, Ring-SK-204-Assembly-Sequence-III.pdf.
  • Twark_Main, 2023-06-10 (reply #3820): 3 vs 4 arms MVP. Post.
  • JohnFornaro, 2023-06-10 (reply #3826): Vast roadmap → wheel. Post. Attachments: Vast-Ring-Station-06-10-23.jpg.
  • lamontagne, 2026-03-22 (reply #5060, 4 likes): Base for larger hotel (4 likes). Post. Attachments: Image11_001.jpg, Image10_000.jpg, Image3_003.jpg, Image53_003.jpg, Image51_001.jpg.