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You’re poking right at the hard part of these forms—global stiffness over long, curved spans is where they get sneaky.

Key stiffness issues in a large double-torus truss
Global ring flexibility (hoop modes): 
The toroidal geometry wants to “ovalize” under asymmetric loads.

Problem: Low in-plane bending stiffness of the ring → large lateral deflections, especially midspan between supports.

Watch for: First few modes being global ovalization or “breathing” of the torus rather than local member bending.

Torsional softness of the ring: 
If the torus is essentially a single-layer truss ring, its torsional stiffness is often weak.

Problem: Eccentric loads (lighting, rigging, façade panels) twist the ring, causing out-of-plane rotations and secondary bending in chords.

Mitigation: Use a closed box-like section at the macro level—e.g., double chord top/bottom with diagonals forming a tube, or two concentric rings tied with radial webs.

Span-to-depth ratio of the truss: 
Long spans with shallow truss depth are inherently flexible.

Rule of thumb: For a primary long-span truss, depth ≈ span/15–20 is comfortable; much shallower and deflections dominate.

In a torus: “Depth” is the radial distance between inner and outer chords (or top/bottom chords if vertical). Too small → poor bending stiffness around the ring.

Local member buckling vs. global stability:

Compression chords: Long, lightly braced chords around the torus are prone to elastic buckling if panel lengths are large.

Bracing density: Panel length and diagonal layout control effective buckling length; large toroidal spans often need tighter panelization than straight trusses.

Support conditions and continuity:

Discontinuous rings: If the double torus is segmented (e.g., four quadrants bolted together), joint flexibility can dominate global stiffness.

Support layout: Few supports → large bending in the ring between them; many supports → more statically indeterminate, but stiffer and more redundant.

How to analyze stiffness (conceptual workflow)
Idealize as a ring/torus beam first (macro model):

Model: Treat each torus as a curved beam with equivalent ?? (bending) and ?? (torsion) derived from the truss.

Goal: Quickly see global deflections, ovalization, and sensitivity to support layout and span.

Derive equivalent section properties from the truss:

Axial stiffness of chords:??eq=∑???cos2(??)
Bending stiffness: Use chord separation (depth) and chord areas to get an equivalent ? about the ring’s local axes.

Torsional stiffness: If you have a closed truss tube, approximate ? from the chord layout; if it’s open, accept that ?? is small and design bracing accordingly.

Refine with a 3D truss FE model:

Nodes: At each panel point along the torus; include both toroids if it’s a “double” system.

Members: Chords, diagonals, verticals, and any cross-ties between the two tori.

Check:

Nodal displacements under worst-case load patterns.

Member forces and utilization.

Buckling factors (linear eigen-buckling) for global modes.

Pay attention to load patterns that “break symmetry”:

Partial loading: Half-ring or quarter-ring loads often govern deflection and member forces.

Eccentric loads: Loads offset from the ring centroid to excite torsion and out-of-plane bending.

Strategies to increase stiffness over long spans
Increase structural depth:

Radial depth: Separate inner and outer chords more; larger radius difference → higher in-plane bending stiffness.

Vertical depth: If the torus is vertical, increase distance between top and bottom chords.

Create a true closed tube:

Double torus as a box: Tie the two tori together with regular radial frames so they act as a single closed section.

Benefit: Huge gain in torsional stiffness and resistance to ovalization.

Densify bracing:

Shorter panels: More nodes, shorter members → higher buckling capacity and better distribution of forces.

Diagonal patterns: Use X-bracing or K-bracing patterns that stabilize both chords effectively.

Stiffen joints and segment connections:

Bolted flanges / sleeves: Ensure segment joints are not the weak link; rotational slop here kills global stiffness.

Pre-tensioned connections: Where possible, use preloaded bolts or clamps to reduce slip.

Optimize support scheme:

More supports: If feasible, add intermediate supports to reduce effective span between supports.

Support stiffness: Model support flexibility (e.g., base plates, anchors) realistically—soft supports can negate gains in the truss.

A quick gut-check for your design
If you tell me:

Major radius (centerline of torus), Minor radius / truss depth, Number of panels, Chord sizes, and Support locations,

I can walk through a rough equivalent ??, estimate deflections over the longest span, and flag where the double-torus concept is likely to feel “soft” versus robust.

What’s the approximate diameter and depth of the double torus you’re thinking about, and is it for a stage, a roof, or something more permanent?

Elon Musk Wants SpaceX to Reach Mars Using Carbon Capture. Here’s How It Could Work

A membrane Sabatier system for water recovery and rocket propellant production ABSTRACT

Gee he is reading our pages....
https://marspedia.org/Sabatier/Water_El … is_Process

Making methane on Mars

Scientists create new way to convert methane into rocket fuel on Mars

No, You Don’t Have To Worry About Emissions From SpaceX’s Mars Rocket

Methane in the Form of Liquified Natural Gas (LNG) Will Power the Next Generation of Rockets

Elon Musk to Launch Carbon Capture Technology

FUTURE OF BUILDING STARSHIP

Mars 2026

yes another curtosocy of Mars society
Propellant production on Mars

Elon Musk announces SpaceX launching new program to use CO2 from atmosphere as rocket fuel Video

Break it! Elon Musk's SpaceX Insane Secret Starship Goals in 2026 Shocked NASA... Video

Here is the But A Closer Look at SpaceX's Mars Plan

Starship video

The 4 crew sleeping quarters is a volume of 125 m cubic meters which with 2.5 m floor to ceiling means 5m by 10 m long but what is missing?
Simple math: 1000 crew / 4 only gives a volume that is incomplete at 250x 125 m^3 = 31,250 cubic meters of volume floor area was also off by a factor of 2 this means a ceiling of 2.5 m x room for 1 of 5m x 2m = 12.5 m^2 or 31.25 M^3 sized for 1 crew member

Hygiene & laundry    1.0–1.5 m²/person @ 2.5 m height    1,000–1,500    2,500–3,750  this is a toilet stall for a man 1.0m x 1.5 m² per crew person x 2.5 m height we might want 2 minimum

Life support machinery    CO₂, O₂, water, waste, tanks, thermal plant    –    5,000–10,000

Waste management    Sorting, storage, processing    –    1,000–2,000 plumbing exits through the floor to a storage tank in the ground

medical care, surgery, recovery Area: 23-28 sq meters per crew patient bed for monitoring, leave space for all side of bed for a minimum to support 50 crew
use 2 crew room for sizing for the operation area

Medical (incl. support)    50 monitored beds @ 23–28 m² + OR, imaging, support    2,000–2,500    5,000–6,250 no area is truly needed but plan for 1 crew needing ICU or direct care

Workspaces & labs    Offices, control, labs, shops (~1.0–1.5 m²/person)    1,000–1,500    2,500–3,750 no area is truly needed but plan for 1 crew needing ICU or direct care

greenhouse which is volume for 1,000 need per single person is 2m x 4m x5m = 40 cubic meter x 1,000 = 40,000 cubic m volume is 4 times to small.  this is 160 m^3 per person for food

galley/kitchen, refrigeration/ freezing, dry food storage
Galley + mess    Seats for 1/3 crew at once (~0.8–1.0 m²/seat) + kitchen    600–800    1,500–2,000

Submarine galleys are highly compact, specialized spaces, often squeezed into less than 100-200 square feet to serve over 100 crew members, requiring multi-functional, durable equipment.

Key equipment includes electric ranges with fiddles, specialized small ovens, deep fryers, and compact, heavy-duty refrigeration. Space is optimized for high-volume cooking in limited, shock-proof areas. Galley Equipment

Requirements Cooking Equipment: Heavy-duty, electric ranges are standard, often featuring "fiddles" (rails) to prevent pots from sliding, measuring roughly 18-1/2" wide x 16-7/8" deep.

Ovens & Kettles: Compact rectangular kettles (approx. 9" x 16") and small-footprint ovens are used to maximize space.

Power Supply: Modern naval galleys require significant power, often around \(14.5\text{\ kW}\) for smaller units, or more for larger crews.Construction: Equipment must be waterproof, shockproof, salt-fog resistant, easy to clean, and durable. 

Galley Design Factors Square Footage: Extremely restricted, often designed for maximum efficiency rather than comfort. Submarine galleys are often in the center of the boat, adjacent to storage for frozen, refrigerated, and dry good's.

Storage: Perishables and dry stores are kept in nearby specialized storerooms, often directly below the galleys.

Efficiency: Due to the small size, equipment must be multifunctional, and layout is critical for workflow, such as integrating cooking surfaces, ovens, and preparation areas into a single, cohesive unit

Submarine mess halls, often called the "crew's mess" or simply the "mess decks," are highly compact, multifunctional social hubs designed to maximize limited space for 150+ sailors. They are characterized by tight, efficient seating, 24/7 service, and, in older vessels, they often functioned as additional sleeping areas.

Mess Hall Area and Layout
Location & Size: Situated in one of the few open-concept areas of the submarine, the mess hall is usually located near the galley (kitchen), which is often described as being roughly the size of a walk-in closet.

Multifunctional Space: In older or smaller submarines, the mess area also served as a berthing (sleeping) compartment.

Atmosphere: It serves as the primary social hub for the crew, used for eating, watching movies, playing games like cards or chess, and holding meetings.

Amenities: The area typically features fixed tables, benches, and a TV for entertainment.

Ventilation: Due to the heat from the galley, these areas often feature exposed, high-volume air ducting.

Seating and Dining Arrangements

Fixed Furniture: Seating consists of fixed benches and tables, often described as a, "small, greasy spoon" diner.

Capacity: The seating capacity is intentionally small, often accommodating only 15 to 24 sailors at a time.

Shifts: Because the crew is large and the space is small, sailors eat in rotating shifts (continuous service).

Buffet Style: Meals are generally served buffet-style, with sailors using metal cafeteria-style trays rather than plates.

Folding Seats: In some configurations, tables are designed to maximize space, with benches that may allow for seating near storage areas or folded bunks.

Differences by Submarine Class
WWII/Older Submarines: Used foldable, portable benches and sometimes required sailors to sit on footlockers.

Modern Nuclear Submarines (e.g., Ohio/Virginia Class): Feature more refined, but still cramped, permanent, fixed-booth seating with specialized,, durable, and sometimes fire-retardant materials.

Officers' Wardroom: Unlike the crew's mess, officers often have a separate, more private, and formal wardroom for dining and confidential meetings.

Key Aspects of Submarine Dining
"Midrats": The galley operates 24/7, providing four meals a day, including "midrats" (midnight rations) for sailors changing shifts.

High-Quality Food: Because of the confined, high-stress environment, submarines are known for having better food than surface ships to maintain morale.

Tight Quarters: The entire space is designed to be efficient, with every square inch utilized for storage, food prep, and serving

Exercise & recreation    ~1.5–2.0 m²/person shared    1,500–2,000    3,750–5,000

Two years

Statute of Limitations on Crimes Such as Illegal Entrance into the US
The statute of limitations for illegal entrance into the United States is generally two years from the date of the commission of the crime. This means that the government has two years from the date of the illegal entry to bring criminal charges against an individual. However, this is a general rule, and specific circumstances may affect the statute of limitations. For example, if the defendant has fled the jurisdiction, the statute of limitations may be tolled until the defendant's return. Additionally, if an individual has entered the country illegally and then commits another crime, the statute of limitations for the illegal entry may be extended to cover the time period of the additional crime. It is always best to consult with an attorney to determine the specific statute of limitations for a particular case.
Cornell University

The principle of double jeopardy protects individuals from being tried twice for the same offense. According to the Fifth Amendment to the U.S. Constitution, no person shall be subject for the same offense to be twice put in jeopardy of life or limb. This means that once a person has been acquitted or convicted, they cannot be retried for the same crime. However, there are exceptions to this rule, such as mistrials, where jeopardy attaches again, and separate sovereigns can independently prosecute the same conduct without violating the double jeopardy principle. Thus, while the general rule is that double jeopardy applies, there are specific circumstances under which it may not be enforced.
legalclarity.org

Astronaut daily CO2 production is about 1kg per person and they consume 1 gallon of water per person.

Thermally-Regenerated 4-Bed Solid Amine CO2 Removal System with Air and Water Save Features (CAMRAS): 400W 120VAC constant power draw for 1 of 4 sequentially heated amine beds.
415W average / 526W peak 28VDC power draw for fans, pumps, and control electronics.
4.71kg of maximum demonstrated CO2 removal capacity per day aboard ISS over a 1,000 day test.
The system is therefore "sized" for 4 astronauts, or 1/250th of our colony's head count.

For a Thermally-Regenerated 4‑Bed Solid Amine CO₂ Removal System with air and water save features (CAMRAS-class) designed for something like ISS/Orion-class flows:

Ballpark dry mass (single unit):  ~80–150 kg
Lower end: aggressively optimized, Orion/short-duration style packaging.
Upper end: ISS-like robustness, more structure, more interfaces.

Installed volume / footprint:  Think in terms of a rectangular box roughly:
Planform footprint: about 0.4–0.7 m²

e.g. something like 0.6 m × 0.8–1.0 m in floor area.

Height: 0.6–1.0 m depending on packaging and access.

So envelope volume: roughly 0.25–0.6 m³ per unit.

Specific capacity (for scaling): 
For crew-sized systems, a CAMRAS-class solid amine 4‑bed system is typically sized around: 4–6 crew per unit at ~0.8–1.0 kg CO₂/day/person

So ~3–6 kg CO₂/day per unit is a reasonable design point.

How to use this for your Mars habitat sizing
If you’re doing system-level mass/volume budgets rather than hardware-level replication, a good parametric approximation is:

Mass per person (CO₂ removal, solid amine, thermally regenerated):

m_{\text{CO₂,person}} \approx 20\text{–}35 \text{ kg/person (installed, including structure & interfaces)}
for continuous, long-duration operation with redundancy.

Footprint per person: ? CO₂,person ≈ 0.05 – 0.10  m²/person assuming you cluster beds into a few larger units rather than one tiny unit per person.

So, for example, for 1,000 crew with N+1 redundancy and some margin, you might budget:
Mass: 1,000 × 25 – 35 kg ≈ 25 – 35  metric tons for the entire CO₂ removal subsystem, including structure, manifolds, and some spares.

Footprint: 1,000 × 0.07 m² ≈ 70 m²
which is then arranged in racks, so actual deck area impact is less if you stack vertically.

Reality check
Because the exact CAMRAS configuration you named is a specific NASA hardware line, the true numbers will depend on:
Mission profile: flow rate, crew count, redundancy, regeneration power limits.
Packaging constraints: rack vs. wall-mounted vs. modular skid.
Integration: ducting, valves, water-save heat exchangers, and control electronics.

926W * 250 = 231,500W of constant power to support CO2 scrubbing for 1,000 colonists, with a 17.75% CO2 removal performance margin for degraded system operation.

Cumulative air mass vented to space over 1,000 days of operation: 16.1lbm, so 4,025lbm over 1,000 days for 1,000 colonists, which equates to 4.025lbm of required atmospheric replenishment per day 78% N2, 21% O2, and 1% Ar.  I've no idea how to source the N2 yet, but the O2 can be provided by CO2 and the Martian atmosphere also contains 2.7% Nitrogen and 1.6% Argon by mass.

Cumulative water mass vented to space over 1,000 days of operation: 67.9lbm, so 16.9775lbm / 2.04 gallons per day for 1,000 people.  The water save feature of CAMRAS is crucial to life support, otherwise 80.4lbm / 9.64 gallons per day would be lost for 1,000 colonists.

Ionomwer Water Processor (IWP) Assembly peak power draw: 195W
Urine Processor Assembly (UPA) active / standby power draw: 424W / 108W
Water Recovery System (WRS; UPA + IWP) time averaged power draw: 743Wh/hr
743W * 250 = 185,750W

ISS Waste Water Recovery Per Day: 34.34 gallons / 130L per day (98% recovery rate)

This implies that total water processing for 1,000 colonists will be 2,146.25 gallons per day.

Minimal Life Support Power Draw: 417,250W

That figure does not include fan-based air circulation / ventilation, waste heat removal, or more advanced life support functions such as hot showers and cooking / cleaning, merely the minimum CO2 scrubbing and waste water recovery to keep 1,000 people alive.

It would be reasonable to assume that 417,250W of power draw is ultimately dissipated as waste heat, which needs to be rejected to space via radiators.  1,000 colonists, all working about as hard as they could sustain for 1 hour, would generate just under 98,000W of waste heat.

The fan power to deliver 15 air changes per hour to a 144,000ft^3 / 4,078m^3 auditorium filled with 1,000 people is 36,000CFM, so 36,000CFM * 0.8W/CFM = 28,800W.  This structure is approximately 31X larger, so we can probably get away with as few as 4 complete air changes per hour because it's so big.  The smaller the interior volume of a structure relative to the number of people inside, the more air changes per hour are required to keep the air fresh.  However, that still bumps our total wattage up to 59,520W.  If we really want to be completely pedantic about this, then 892,800W is required to provide 15 air changes per hour for a 125,000m^3 internal volume structure.  It'll be like living inside a wind tunnel, though, so perhaps that's a bit over-the-top.

3MW worth of power for 1,000 colonists is likely more than sufficient for basic life support functions, to include hot showers and interior lights, especially if we use some of that waste heat to warm up our frosty cold fresh water supply.

would like to find foot print measurements for Ionomwer Water Processor (IWP)
Urine Processor Assembly (UPA)
Water Recovery System (WRS; UPA + IWP)
I dug through the available sources, but none of the search results provide physical footprint measurements (height × width × depth or mass/volume envelope) for:

Ionomer Water Processor (IWP)

Urine Processor Assembly (UPA)

Water Recovery System (WRS = UPA + WPA/IWP)

The documents found describe function, technology, upgrades, and performance, but not physical dimensions.
Here is what the searches actually contained:

What the sources do cover
IWP: Technology description, membrane design, SBIR announcements, and system goals (e.g., 98% recovery)

UPA: Technical papers on upgrades, distillation assembly, and system behavior, but no physical envelope

WRS: High‑level ISS water management descriptions, but no hardware dimensions

Why the data is missing
NASA typically publishes mass, power, and performance for ECLSS hardware, but footprint dimensions are usually buried in:

internal configuration drawings

ISS rack integration documents

payload accommodation specs

NASA ECLSS ICDs (Interface Control Documents)

These are rarely available in public-facing technical papers.

What I can give you right now (based on known ISS architecture)
Even though the search didn’t return explicit numbers, we can anchor the expected footprint because:

1. UPA and WPA/IWP are housed in standard ISS racks
Both systems are installed in US Lab racks (ISPRs).
A standard ISPR (International Standard Payload Rack) has known dimensions:

Parameter    ISPR Value
Height    2.0 m
Width    1.05 m
Depth    0.86 m
Usable internal volume    ~1.57 m³
Max mass    ~700 kg
So the maximum possible footprint for UPA, WPA, or IWP is constrained by the ISPR envelope.

2. UPA occupies one full rack (LAB1P4)
This is explicitly stated in NASA documentation:

“The Urine Processing Assembly (UPA) was installed in LAB1P4 during ULF‑2 as part of the Water Recovery System (WRS).”

Thus, UPA footprint ≈ 1 ISPR rack.

3. WPA (Water Processor Assembly) also occupies one rack
The WPA is the other half of the WRS.
The IWP is intended as a future replacement for WPA, so its footprint is expected to be ≤ 1 ISPR rack.

4. WRS (UPA + WPA/IWP) = 2 racks total
This is consistent with all ISS ECLSS documentation.

Practical engineering summary
Here are the best available footprint estimates based on rack constraints:

Ionomer Water Processor (IWP)
Footprint: ≤ 1 ISPR

Approx. max dimensions:
2.0 m (H) × 1.05 m (W) × 0.86 m (D)

Likely smaller, but no public source gives exact numbers.

Urine Processor Assembly (UPA)
Footprint: 1 ISPR (LAB1P4)

Dimensions:
2.0 m × 1.05 m × 0.86 m (rack envelope)
Internal hardware occupies most of the rack volume.

Water Recovery System (WRS = UPA + WPA/IWP)
Footprint: 2 ISPR racks

Dimensions:
2 × (2.0 m × 1.05 m × 0.86 m)
Total width: ~2.1 m when racks are side‑by‑side.

If you want the exact hardware dimensions
I can help you get them, but I need to know which path you prefer:

Option A — I search for NASA rack integration drawings
These sometimes include exact hardware envelopes.

Option B — You want engineering‑grade estimates
I can derive realistic dimensions based on:
component masses
pump and distillation assembly sizes
membrane module geometry
thermal control hardware
avionics packaging

Option C — You want footprints for Mars ISRU planning

I can scale these systems for:
1–6 crew
1000‑crew colony
surface vs. pressurized habitat integration
power and mass budgets
Which direction would you like to go?

scale for 10 crew

See my thinking
For 10 crew, we can treat the ISS WRS (UPA + WPA/IWP) as our baseline module and scale from there.

Quick sizing summary for 10‑crew WRS
Item    ISS baseline (6–7 crew)    Scaled for 10 crew    Notes
Crew supported    6–7    10    Linear scaling with margin
UPA racks    1 ISPR    1–2 ISPR    Depends on turndown/redundancy
WPA/IWP racks    1 ISPR    1–2 ISPR    Higher throughput or N+1
Total WRS racks    2 ISPR    3–4 ISPR    Likely 3 if aggressively optimized
Rack footprint (each)    2.0 m H × 1.05 m W × 0.86 m D    same    ISPR standard
So for 10 crew, you’re realistically looking at:

Minimum aggressive design:
3 racks total (e.g., 1.5× ISS capacity with higher‑throughput internals)
Footprint ≈ 2.0 m H × 3.15 m W × 0.86 m D
Conservative / high‑reliability design:
4 racks total (2× UPA, 2× WPA/IWP or 1.5× + redundancy)
Footprint ≈ 2.0 m H × 4.2 m W × 0.86 m D

How I’m scaling from ISS
1. ISS design point
The UPA is explicitly described as being designed for 6–7 crewmembers.
The WRS (UPA + WPA) on ISS supports that crew size with some margin and operates near continuous duty.

So: Capacity per ISS WRS ≈ 6.5  crew (midpoint)

2. Linear flow scaling to 10 crew

Assuming roughly linear scaling of water production/processing with crew count:

Scale factor = 10 6.5 ≈ 1.54
That means you need about 1.5× the ISS WRS throughput to support 10 crew with similar margins.

3. What that means in hardware

You have three main strategies:

A. Higher‑throughput internals, same rack count (2 racks)
Push pumps, contactors, distillation, and membranes harder.
This increases power, heat rejection, and wear, and leaves less margin.
For a long‑duration or Mars‑class system, this is usually too aggressive.

B. 1.5× capacity in 3 racks (likely sweet spot)

Example layout:
1.5× UPA capacity in 2 racks (primary + partial redundant/parallel unit)
1.5× WPA/IWP capacity in 1 rack with denser packing and improved tech

This gives you 10‑crew capacity with some redundancy and keeps integration manageable.

C. Full 2× capacity in 4 racks (robust, N+1)

Essentially two ISS‑class WRS lines, cross‑plumbed.

You can lose a whole UPA or WPA line and still support the crew at reduced but survivable capacity.
Best for deep‑space or early Mars base where repair and resupply are slow.

Footprint numbers you can actually design around Using the ISPR envelope:

Single rack (UPA or WPA/IWP or IWP‑derived module):
Height: 2.0 m
Width: 1.05 m
Depth: 0.86 m

Then:
3‑rack WRS (10 crew, optimized):
Width: 3 × 1.05 m = 3.15 m
Height: 2.0 m Depth: 0.86 m

4‑rack WRS (10 crew, robust):
Width: 4 × 1.05 m = 4.2 m Height: 2.0 m Depth: 0.86 m