Modular Mars

[Vanspace]

I believe the party favor style will be used but only in a limited way. The best use of the party favor idea is as cargo in the engine bay pods. That way blowing them can lay them out as the very first thing done on the surface. The early and simple deployment allows enough electrical power to start all of the other deployment activities.

...
...
Lamontange's and other deployment systems need half the mass delivered per watt. They can accurately lay out a grid so connecting wires length can be standardized. They can automatically anchor the roll so wind doesn't move it.

Party favors make lots of sense for the very first power laid out but have huge drawbacks for installing longterm power.

You have o good point.
The one drawback to Lamontagne’s proposal as shown in the above image is that the coil is unrolled at the bottom. This means that the whole panel strip is dragged along the ground surface as it unrolls. Rough or jagged terrain would likely damage the solar cell strip.

I think we could alleviate this problem by pulling out the coil rather than puling the end of the strip.  Place a dowel through the center of the coli and roll out by pulling on the ends of the dowel. As the coil unrolls, the laid-down portion of the strip stays in place. This hybrid method would be easier to control, would avoid friction with the ground, and would still retain the advantage of Elon’s blowout.

Personally, I favor using a standard plastic mulch layer design see pic. It is the tool every farmer uses to lay plastic film in secure straight lines. If you have something that can pull Lamontanges design, it can pull this


That said, the party favor method really only has advantages when there is no ground prep or way to move a dispenser. That situation does occur before anything is taken out of the cargo hold. Which is why blowing them out of the engine cargo pods as the very first thing makes sense. It ensures there is enough power for the cargo handling system to deploy the main system. For any other deployment, a high chance of twisted or crooked PV, high chance of rocks blocking roll out all at a cost of twice the mass per watt doesn't make sense. If you have a rover/cybertruck on the ground a dispenser for single layer film is the way to go.

[Twark_Main]

The first three things I see happening are "rolling" out the solar panels (includes the electrical cables) to connect a solar energy starship that is full of batteries and their controllers.  This provides a distribution point (of which there may be more than one initially).
...
...

...
...
I believe Elon has described solar rollout as similar to using a party-favor “blowout" to uncoil a linear strip of flexible solar panels.

AIUI Elon’s blowout would have the solar cells s embedded onto a flat balloon-like strip. The balloon would be rolled up into a tight coil, which would be under tension to maintain the coil shape. To activate, air (Mars atmosphere) would be pumped into the balloon, forcing it to uncoil into a straight panel with solar cells facing upward.

Some party blowouts:

I believe the party favor style will be used but only in a limited way. The best use of the party favor idea is as cargo in the engine bay pods. That way blowing them can lay them out as the very first thing done on the surface. The early and simple deployment allows enough electrical power to start all of the other deployment activities.

However, because the party favor idea requires a tube of film to inflate (rather than just one layer) it doubles the mass of film required per watt.

That would only be true if the inflating tube covers the entire width of the roll. But I expect we would see several smaller tubes that in total only cover a fraction of the width.

Secondly, try actually blowing a party favor sometime. From my experience, most of the time the party favor will not roll and unroll smoothly. Bends, twists and other problems during inflation are very common and generally only smooth out at the end when a large overpressure is holding the whole tube stiff. On mars that would mean using high pressure to straighten the tube and thus drag over sharp rocks with all the risk that entails. No matter how well you line it up and aim, actually rolling out the way you intend is mostly a matter of luck. Every rock and bump will change the direction at the least if not stop the rollout.

This is exactly why you want multiple tubes. During deployment you can alter pressure from side-to-side and actively "steer" the roll where you want it to go.

The idea of using high pressure to straighten/drag the tube after full deployment is, indeed, a bad idea.

Then there is wind on a large plastic sheet with no hold downs.

I suspect you must be envisioning something like a plastic mulch layer.



(Fun aside for anyone who thinks it's a good idea to mix plastic with their soil on a farm: plastic mulch breaks down into microplastics, and plants absorb microplastics through their roots and into the edible parts of the plant.)


For deployment on harder surfaces, you could alternately transport rocks or loose regolith a short distance and drop them along the edge. This would work equally well for both methods.

With integrated inflation deployment tubes you have still a third option: somehow pump or blow some ballast material into the cavity to weigh it down along the entire length. Perhaps this could be water or fluidized water-regolith slurry. Obviously this idea isn't fully "baked" and has multiple issues (freezing prematurely, water sublimates over time through pinholes, tube clogging with regolith before it fills completely), but I'd be interested to hear suggestions for how this could be made workable. Using in-situ material is preferred of course, but that comes with its own challenges.

Lamontange's and other deployment systems need half the mass delivered per watt.

The backing film is only a fraction of the mass of the total solar system. So while arguably the "deployment system" is half the mass, the total mass-per-watt wouldn't show that much difference.

And it's not "half," as discussed upthread.

And you must not be counting the mass of the (imo unnecessary) box. That could easily outweigh the mass savings in thin films. I envision a simple frame to support the hollow axle "core." See how rolls of paper are handled in industry.

They can accurately lay out a grid so connecting wires length can be standardized. They can automatically anchor the roll so wind doesn't move it.

Pretty sure I've already addressed both of these.

Party favors make lots of sense for the very first power laid out but have huge drawbacks for installing longterm power.

I disagree about "huge" drawbacks, but I do agree that the party favor deployment is unnecessary once you have human teleoperators who can reliably unroll it with a robotic roll handler.

[steveleach]

Very interested in the ground conditions at the landing site. Last year a NASA probe tried to drill for water but hit very hard regolith or stone and couldn’t complete the operation. If the ground at the SS landing site is this hard, then the procedure for digging a shallow trench with a loader, as implied by the my sketch above, won’t work. Some other approach will be needed.

That is why I think any initial build up on Mars will be slow.  These issues have to be figured out or a lot of money and time will be wasted.

Sometimes "wasting" time and money is a good thing, when the cost of not doing something is very high.

SpaceX seem very willing to take this approach with Starship, and will likely be just as willing with a Mars base/settlement/colony/city.

I disagree.  I don't think SpaceX is wasting time and money right now on developing Starship.  They are doing rapid prototyping in an efficient manner.  One Mars if you try something and it doesn't work you have to wait 26 months to try again.  With Starship they can do 10 major revisions in a year.  To try 10 major revisions on Mars will take you 2 decades.  That's a big difference in both time and money even if your transportation costs are negligible.

Maybe, but then again maybe they will just send 10 different options at the same time and see which works. Or, more likely, three variants of four pluggable modules to give 12 combinations, of which they only need one to work.

The constraints are different but the philosophy is the same.

[Vanspace]

...
...
I believe Elon has described solar rollout as similar to using a party-favor “blowout" to uncoil a linear strip of flexible solar panels.

AIUI Elon’s blowout would have the solar cells s embedded onto a flat balloon-like strip. The balloon would be rolled up into a tight coil, which would be under tension to maintain the coil shape. To activate, air (Mars atmosphere) would be pumped into the balloon, forcing it to uncoil into a straight panel with solar cells facing upward.

Some party blowouts:

I believe the party favor style will be used but only in a limited way. The best use of the party favor idea is as cargo in the engine bay pods. That way blowing them can lay them out as the very first thing done on the surface. The early and simple deployment allows enough electrical power to start all of the other deployment activities.

However, because the party favor idea requires a tube of film to inflate (rather than just one layer) it doubles the mass of film required per watt.

That would only be true if the inflating tube covers the entire width of the roll. But I expect we would see several smaller tubes that in total only cover a fraction of the width.

You are correct to a point, yes there are ways to use tubes less than the full width and thus less than doubling weight. But every sq cm of extra plastic for makeing those tubes that is only used during deployment is parasitic weight reducing the wattage deployed. Additionally, that also means a number of seam welds running the length of of your solar panel right where you want the cells to be printed.

Secondly, try actually blowing a party favor sometime. From my experience, most of the time the party favor will not roll and unroll smoothly. Bends, twists and other problems during inflation are very common and generally only smooth out at the end when a large overpressure is holding the whole tube stiff. On mars that would mean using high pressure to straighten the tube and thus drag over sharp rocks with all the risk that entails. No matter how well you line it up and aim, actually rolling out the way you intend is mostly a matter of luck. Every rock and bump will change the direction at the least if not stop the rollout.

This is exactly why you want multiple tubes. During deployment you can alter pressure from side-to-side and actively "steer" the roll where you want it to go.

The idea of using high pressure to straighten/drag the tube after full deployment is, indeed, a bad idea.

The multiple tube idea has merit but attempting to control the roll around say a rock, by using variable pressure from the far end of the stretchy tube to differentially leverage the coil movement for steering seems hard. I am not saying it isn't possible but I suspect landing a booster may be an easier control system to create.

Then there is wind on a large plastic sheet with no hold downs.

I suspect you must be envisioning something like a plastic mulch layer.



(Fun aside for anyone who thinks it's a good idea to mix plastic with their soil on a farm: plastic mulch breaks down into microplastics, and plants absorb microplastics through their roots and into the edible parts of the plant.)

Yep absolutely correct although I showed a much smaller one suitable for small tractors or horses, there are even hand pulled units commercially available. This is very well understood technology.

As to the aside, those are earth problems, plastic decay into plants and the ecosystem don't matter with no plants or ecosystem. In a few thousand years when it might interfere with the budding martian ecosystem I suspect they can deal with it.

For deployment on harder surfaces, you could alternately transport rocks or loose regolith a short distance and drop them along the edge. This would work equally well for both methods.

With integrated inflation deployment tubes you have still a third option: somehow pump or blow some ballast material into the cavity to weigh it down along the entire length. Perhaps this could be water or fluidized water-regolith slurry. Obviously this idea isn't fully "baked" and has multiple issues (freezing prematurely, water sublimates over time through pinholes, tube clogging with regolith before it fills completely), but I'd be interested to hear suggestions for how this could be made workable. Using in-situ material is preferred of course, but that comes with its own challenges.

You are running into chicken and egg problems here. If you have something that can move rocks and regolith, you don't need to use the party favor system. Same problem with filling the tubes. How are you getting the water and regolith supplies if you haven't rolled out your power system?

Lamontange's and other deployment systems need half the mass delivered per watt.

The backing film is only a fraction of the mass of the total solar system. So while arguably the "deployment system" is half the mass, the total mass-per-watt wouldn't show that much difference.

And it's not "half," as discussed upthread.

And you must not be counting the mass of the (imo unnecessary) box. That could easily outweigh the mass savings in thin films. I envision a simple frame to support the hollow axle "core." See how rolls of paper are handled in industry.

We must be envisioning different things. The panels are by mass, almost entirely poly film with a very thin coating of PV cell. Adding extra poly film to make tube structures increases mass per unit of PV. Keeping the tubes less than full width prevents the mass from fully doubling but it does not come free.

How many deployment mechanisms do you envision? ISTM that no matter how you do it, the rolls of film have to be moved out of the cargo hold and to where ever it will be deployed. If you can move the roll that well, you certainly have the ability to position it onto the mulch layer. The one I showed is likely less than 50kg and the only reason you would need a second is for backup. Its not like they wear out.

They can accurately lay out a grid so connecting wires length can be standardized. They can automatically anchor the roll so wind doesn't move it.

Pretty sure I've already addressed both of these.

Party favors make lots of sense for the very first power laid out but have huge drawbacks for installing longterm power.

I disagree about "huge" drawbacks, but I do agree that the party favor deployment is unnecessary once you have human teleoperators who can reliably unroll it with a robotic roll handler.

That last line really hits the nail. Your system requires teleoperation of a complex novel feedback control system yet to be developed. Mine requires something that can drive in straight lines unassisted. Which is also already existing technology.

[Ionmars]

We seem to agree that the first landed cargo SS should just throw a coil of solar cells (hooked up to electrical lines) out the payload door and roll them to wherever.

The second and following landers should lay out neat rows as is carried out in agriculture. Closely packed rows of paneling would maximize the number of cells that cover each hectare of solar farm. This is necessary to generate enough energy for the huge demands of colonization.

One approach is to employ a backhoe/loader (image below) to clear out a path ahead of unrolling the solar coils. The pan on the loader end would smooth out a path and shove aside rocks as it goes. For a boulder buried in its path, the vehicle would turn around and employ the bucket to dig up the rock, then use the pan to shove it out of the way. For really large boulders, the vehicle would clear a path around it. By this means the coil unwinder robot would follow well-planned paths.

[Ionmars]

For several years of my life, I actually used a backhoe/loader to dig trenches to install and repair water and sewer lines. It was a lot of fun. 

[akm]

All mars base build up scenarios require landing several tall skinny rockets near each other.  The first volley needs to set up some sort of guidance and weather system.   Maybe a set beacons around the landing sight.  Maybe something simple like corner cubes.  May the first system should have very wide folding legs like F9, and put solar cells on the inside, giving  power and the ability to land on rougher terrain. 

[zodiacchris]

With the modular approach it would make sense to park landed habitat SS in close proximity to each other. Some variation of battery driven roll lift would be required to move the SS from the landing area to the settlement site. Parked in close proximity with their legs offset, short prefab sealed bridges, similar to the access bridge on 39A could connect the airlocks. Used with a central connection node, this would allow to connect multiple SS without much drama provided they are parked accurately.

[GregTheGrumpy]

Picking up from my idea from above, focused on the laying of the electrical panels.  I do see them placed much like paper rolls in a crate lowered from a bottom storage compartment.  One of the storage compartments would contain a rover/tractor unit.  It should have a blade and a pair of articulated pincher/grabber arms.  The first pass out of the box (after calibration via the telerobotics operator) is to smooth a path/pad for the rolls of film.  After the path/pad is cleared of anything significant (I don't think we need roller rink smooth) the rover unit pulls up to one of the rolls, lifts it clear of the box, places it at the start of the path and pins it down (think tent peg, maybe one of the screw kind).  Then in picks up the roll again and heads straight out unspooling the film on the path.  When it get to the end it then pins that end down as well.  It then goes back and pins the sides of the film down (before laying the next roll).  Repeat laying rolls on the smoothed surface.

Once laid out, the connector cables are attached (I would think a redundant pair of cables) hook up all of the ends nearest to the battery ship and finally ends with the 'left and right' ends spooled out and finally plugged into the battery ship.

The articulated arms would have a variety of tools stacked on the rover and could plug out ends (like an autochanger on a CNC) to accomplish things from small manipulation (pluggin in the cables) to digging and looping a "chain" (of whatever substance) around something that needs to be dragged.

Anyway, that's my thoughts on the battery ship setup.  Everything I've described is well within current technology and could be tested in a variety of locales (sandy, scree, rock).

BTW, the Mars mole didn't hit something hard, it lacked soil friction to prevent each hammer from bouncing it out of the hole.  We learned a lot about that particular soil issue right there.  However, having a jig screw a 'dog run peg' into the ground under pressure from the arm to an appropriate depth (say 1 meter) should not be a problem.  We're just trying to keep the panels from moving while deploying and from winds jostling them about.

-gg

[Vanspace]

We seem to agree that the first landed cargo SS should just throw a coil of solar cells (hooked up to electrical lines) out the payload door and roll them to wherever.

The second and following landers should lay out neat rows as is carried out in agriculture. Closely packed rows of paneling would maximize the number of cells that cover each hectare of solar farm. This is necessary to generate enough energy for the huge demands of colonization.

One approach is to employ a backhoe/loader (image below) to clear out a path ahead of unrolling the solar coils. The pan on the loader end would smooth out a path and shove aside rocks as it goes. For a boulder buried in its path, the vehicle would turn around and employ the bucket to dig up the rock, then use the pan to shove it out of the way. For really large boulders, the vehicle would clear a path around it. By this means the coil unwinder robot would follow well-planned paths.

So if you leave off the cabin and the attachments from your pic, what its left is a generic farm tractor. Take a cybertruck skateboard add the front and back accessory attachment systems, put on mars wheels. Viola a Mars Tractor! A single skateboard should be able to take a large variety of attachments from manipulator arms, excavator buckets, cranes, winches, grading blades, jackhammers, pinchers, plastic layers and maybe things like 3D Print Heads for mud habitat. Expanding capability becomes a matter of adding to the colony inventory of attachments. Expanding work produced is a matter of increasing the number of skateboards.

I guess the point here is that early adoption of a standard rover body with standard attachment interface reduces mass that must be transported to achieve any given production rate or capability. I can easily see needing to bulldoze, scoop, drill, lever, push, compact, smooth out, spread and otherwise apply work to dirt to achieve most colony goals. PV deployment, Habitat placement/burial, landing pads, storage pads, exploration, wire pulling and other tasks have already been identified for rover/teleoperation/autonomous operations. Avoiding specialized vehicles from the beginning increases growth and capabilities while reducing mass transported.

[Vanspace]

Picking up from my idea from above, focused on the laying of the electrical panels.  I do see them placed much like paper rolls in a crate lowered from a bottom storage compartment.  One of the storage compartments would contain a rover/tractor unit.  It should have a blade and a pair of articulated pincher/grabber arms.  The first pass out of the box (after calibration via the telerobotics operator) is to smooth a path/pad for the rolls of film.  After the path/pad is cleared of anything significant (I don't think we need roller rink smooth) the rover unit pulls up to one of the rolls, lifts it clear of the box, places it at the start of the path and pins it down (think tent peg, maybe one of the screw kind).  Then in picks up the roll again and heads straight out unspooling the film on the path.  When it get to the end it then pins that end down as well.  It then goes back and pins the sides of the film down (before laying the next roll).  Repeat laying rolls on the smoothed surface.

Once laid out, the connector cables are attached (I would think a redundant pair of cables) hook up all of the ends nearest to the battery ship and finally ends with the 'left and right' ends spooled out and finally plugged into the battery ship.

The articulated arms would have a variety of tools stacked on the rover and could plug out ends (like an autochanger on a CNC) to accomplish things from small manipulation (pluggin in the cables) to digging and looping a "chain" (of whatever substance) around something that needs to be dragged.

Anyway, that's my thoughts on the battery ship setup.  Everything I've described is well within current technology and could be tested in a variety of locales (sandy, scree, rock).

BTW, the Mars mole didn't hit something hard, it lacked soil friction to prevent each hammer from bouncing it out of the hole.  We learned a lot about that particular soil issue right there.  However, having a jig screw a 'dog run peg' into the ground under pressure from the arm to an appropriate depth (say 1 meter) should not be a problem.  We're just trying to keep the panels from moving while deploying and from winds jostling them about.

-gg

I think the real difference between your idea and mine is if there is a weight savings between your tent pin driver / unspooler combo and my plastic mulch layer. At say 50kg each I suspect that sending all of them is the sort of "throw mass at the problem" solution that will happen. With a standardized rover, doing all of them adds only the mass for more attachments. All three tasks (pegs setting, unspooling, plastic spreading) are likely to have lots of uses.

Your idea I really like is the idea of the manipulator arm having lots of autochanger heads stored on the rover. It might be generally useful enough to make the manipulator arm the center attachment for all rovers. The ability to fix small problems on or near the rover with a set of tools onboard (screwdrivers, wrenches, drivers, clamps ect) massively increases the reliability and flexibility of the overall system.

[Ionmars]

In Reply #29 Vanspace identified a need for a standard tractor/rover body with many attachments:

"I guess the point here is that early adoption of a standard rover body with standard attachment interface reduces mass that must be transported to achieve any given production rate or capability. I can easily see needing to bulldoze, scoop, drill, lever, push, compact, smooth out, spread and otherwise apply work to dirt to achieve most colony goals...”

The loader/backhoe I suggested above in Reply #24 fits well within Vanspace's concept. The bucket arm and the loader pan can be readily detached from the main tractor body by a knowledgable mechanic. This would result in a 3-module breakdown that could be packed into an SS cargo bay for transit to Mars.

[Twark_Main]

The multiple tube idea has merit but attempting to control the roll around say a rock, by using variable pressure from the far end of the stretchy tube to differentially leverage the coil movement for steering seems hard. I am not saying it isn't possible but I suspect landing a booster may be an easier control system to create.

Strongly disagree. It's not much harder than "if it goes right, steer left. If it goes left, steer right." Much simpler than the G-FOLD landing algorithm.

As to the aside, those are earth problems, plastic decay into plants and the ecosystem don't matter with no plants or ecosystem. In a few thousand years when it might interfere with the budding martian ecosystem I suspect they can deal with it.

And I would agree. That's why it was an "aside."

You are running into chicken and egg problems here. If you have something that can move rocks and regolith, you don't need to use the party favor system. Same problem with filling the tubes. How are you getting the water and regolith supplies if you haven't rolled out your power system?

Well the simplest option is to just deploy it unballasted and hope you don't have a windstorm before you can fill it. With planning and backup PV rolls, it actually might not be so crazy.

But yes, that's one of the main challenges I mentioned.

We must be envisioning different things. The panels are by mass, almost entirely poly film with a very thin coating of PV cell.

Yes we are. I was picturing the PV cells as outweighing the backing film.

How many deployment mechanisms do you envision? ISTM that no matter how you do it, the rolls of film have to be moved out of the cargo hold and to where ever it will be deployed. If you can move the roll that well, you certainly have the ability to position it onto the mulch layer. The one I showed is likely less than 50kg and the only reason you would need a second is for backup. Its not like they wear out.

My worry with relying on a mulch layer is that it requires a relatively thick layer of loose regolith, while early landing sites will likely be chosen to avoid exactly that surface composition.

I disagree about "huge" drawbacks, but I do agree that the party favor deployment is unnecessary once you have human teleoperators who can reliably unroll it with a robotic roll handler.

That last line really hits the nail. Your system requires teleoperation of a complex novel feedback control system yet to be developed.

You misunderstand me. I'm talking about teleoperating robotic handling vehicles, not simple inflation-deployed rolls.

And again, the entire point of the inflation deployment mechanism is to avoid exactly that type of complexity.

Mine requires something that can drive in straight lines unassisted. Which is also already existing technology.

Where exactly is this "existing technology" to autonomously plan paths over unimproved surfaces (ie off road, not Tesla Autopilot) and execute them with high reliability?

And how could you possibly think that this is an easier control problem than steering an unrolling coil? 

[Norm38]

Go look at the Boca Chica video right now of the new high bay.  They're putting it up in prefab panels.  It's like watching a lego set get built.

What do you think gets shipped to Mars in flat packs?

Get Ikea on it.  Basically Scandanavia.

They do really good tunnels and modular funiture.

SpaceX Mars, brought to you by Ikea.  Enjoy your stay at the Sheraton.

[TheRadicalModerate]

You definitely need to have an idea of what equipment needs to be on Mars, but the "when" is likely to inform the "what".

Here's my brain-dump of what I think is the bare minimum test campaign to get humans on the surface.  There's a little bit of human-oriented equipment involved, but it's almost an afterthought to the major payloads that need to land, deploy and be tested before you can send a human crew.  They are, in likely order of development:

1) A mobile payload I'm calling the "refueler".  It's a ground tanker, one (big) tank, with a cryocooler, capable of handling LH2, LOX, and LCH4.  It's launched with a full load of LH2 (I'm too lazy to do the computation, but I'm pretty sure it'll fit), which is then used as feedstock to test the Sabatier system before water mining is up and running.  This will also be used to scavenge enough prop from other vehicles to ensure that at least one of them can do a Mars Ascent and Earth EDL (MAEEDL) test, even if the Sabatier system doesn't work.

2) A power system.  Nukes, solar, I don't care.  But it needs to be sized large enough to support the Sabatier, the refueler, and the water prospector in their goal to finish a large enough load of prop before the next window.  I suspect that this will consume an entire Starship.

3) A Sabatier payload.  It gets LH2 feedstock from the refueler.  If the test goes well, the methalox will be used for a second MAEEDL test.  Note that there's a tricky logistical problem:  The refueler has to hold the LH2 until the Sabatier can ingest it all.  Unless we want two refuelers, we have to be willing to abandon the LH2 in favor of scavenging enough prop from the other landed Starship to ensure that at least one MAEEDL test occurs in the second window of the campaign.  Note that scavenging implies some degree of cryocooling for the methalox remnants.

4) A water prospector payload.  I suspect that this gets co-manifested with the Sabatier system.  This has two goals:  First, it's a proof-of-concept platform for a full-scale miner.  Second, it needs to determine whether its current site is a viable place for a base.

The above are all needed for launch window #1, if SpaceX wants to get crews to the surface ASAP.  First available window is Sep-2022.

5) High-scale water miner.  This is the water prospector's big brother, and must be able to mine enough water to provide at least one MAEEDL plus crew consumables per synod.

6) Water electrolysis and LH2/LOX storage system.  This probably turns out to be the refueler's big brother.  Again, the bare minimum is enough feedstock to provide for at least one MAEEDL plus crew consumables per synod.

7) Mandatory crew support payloads.  This is anything that needs testing before the crew gets there.  It might be a hab pilot, but the crew can live in the Starship if they have to.  Rovers, airlock systems, greenhouses, closed-cycle ECLSS test equipment... Not sure what goes in here.  I'm pretty sure it'll be something.

#5-#7 need to be ready for the second launch window, in Oct-2024.

8) Crew-certified Starship.  Kinda goes without saying, but you're not sending people to Mars until there's a fairly good chance they won't die.

9) Other crew support payloads, which can be tested with the crew on Mars.  Nothing mission-critical, but this could include things like habs, more power-dense rovers, and a wide variety of stuff you need for a real live base.

#8-#9 need to be ready for the third launch window, in Nov-2026.

Here's a cheesy PERT chart that shows how it all fits together:




The critical path looks like this:

Now to Sep-2022:
SH/Starship to orbit.
Modest reuse (enough to make refueling possible) needs to work.
Refueling itself has to be fairly routine.
Power, Sabatier, water prospector, and refueler payloads need to be developed.

Sep-2022 Earth-Mars Window:
Refueler, Power, and Sabatier/Prospector Starships launch.  They need enough extra prop that the refueler can scrape together a MAEEDL mission, even if Sabatier doesn't work well.
You can do multiple copies of this, to different sites.  At least one refueler and one of some other Starship need to survive Mars EDL to enable the MAEEDL mission.

Oct-2024 Mars-Earth Window (time is approximate):
MAEEDL mission #1 goes with prop scavenged from whatever lands.
If Sabatier is successful, MAEEDL #2 uses its methalox.

Oct-2024 Earth-Mars Window:
Water miner, electrolysis/cryocooler, and mandatory crew support payloads launch, in addition to version 2 of whatever didn't work so well in the previous synod.

2024-2026 Mars Operations:
Integrated use of power, water miner, electrolysis/cryocooler, Sabatier must prove that they can produce a MAEEDL's worth of prop by the 2026 window.  There are probably ways to relax this constraint a bit, by scavenging prop from multiple Starships, or by being comfortable enough with the ISRU system that enough prop for a 2028 MAEEDL to take the crew home is a sure thing.

On Earth in the 2024-2026 synod:
At least one of the MAEEDL tests has to have been successful.

Nov-2026 Mars-Earth window:
If the MAEEDL tests were unsatisfactory, everything's going to get pushed a synod, and a successful MAEEDL test has to be possible from some site on Mars in this window.  Logistics will have to be planned accordingly.  Note that this is the period where crew certification of Mars and Earth EDL have to be completed.  Launch would be nice, but there's always D2 to get crews to LEO.  No such luck on the way back from Mars, though.

Nov-2026 Earth-Mars Window:
If everything goes perfectly:  Crew launches!

Dec-2028 Mars-Earth window:
Crew can return if necessary.

Dec-2028 Earth-Mars window:
Base operations begin.

[Ionmars]

TheRadicalModerate, I think your program schedule is good and should be adopted for our discussion. Not that we might not quibble with some details; like some of the dates are different from SpX. Which source has the more feasible date projections??

[TheRadicalModerate]

TheRadicalModerate, I think your program schedule is good and should be adopted for our discussion. Not that we might not quibble with some details; like some of the dates are different from SpX. Which source has the more feasible date projections??

This is pretty much from first principles for me, so I'm not surprised that there are differences.

[Twark_Main]

Go look at the Boca Chica video right now of the new high bay.  They're putting it up in prefab panels.  It's like watching a lego set get built.

What do you think gets shipped to Mars in flat packs?

Get Ikea on it.  Basically Scandanavia.

They do really good tunnels and modular funiture.

SpaceX Mars, brought to you by Ikea.  Enjoy your stay at the Sheraton.

Yep, this is exactly my line of thinking in the system I'm proposing in the Amazing thread (here and here).

All the "grid pieces" wouldn't be that much different from existing prefab buildings (essentially just I-beams with connectors). The outer panels would all be identical (roof, wall, floors) made from stamped sheet metal or molded reinforced polymer, and they nest like bowls for efficient transport. Special panels with unique geometry would be needed for edges and corners.

So essentially you can build the entire pressure vessel using only 4 different unique parts (plus fasteners). And this pressure vessel can be have any X x Y x Z dimension that's an integer multiple of the grid size, without needing a factory re-tooling to make thicker and larger diameter cylinders and domes. This is nice for mission flexibility, repairability, simplicity, payload cost, and ease of eventual in-situ production.


There's two main challenges I see: reliably sealing all those joints, and setup labor. Conceivably this could be solved by some combination of assembly robots and self-deploying design.

[kkattula]

TheRadicalModerate, I have to question your MAEEDL using scavenged propellant.

Even for a relatively slow return, and a nearly empty Starship, (7.8 km/s dv & 120 t, plus 20 t landing prop.), it needs approximately 1000 t of propellant.

Three ships with a max payload of 150 t each can't possibly bring that much, even if the entire payload is devoted to extra propellant. They can't land with payload and significant extra propellant, they'll be too heavy for EDL, as designed.

IMO the EDL mass is likely to be lower if anything for early missions to reduce risk and increase margins. So maybe you get a few tons, or at best tens of tons, of left over propellant per ship. Not going to be enough unless they send at least 6 dedicated tankers, as well as the actual cargo ships.

I think they have to get ISRU working to test MAEEDL, and they'll wait for a crew to do ISRU at that scale.

[Ionmars]

Yep, this is exactly my line of thinking in the system I'm proposing in the Amazing thread (here and here).

All the "grid pieces" wouldn't be that much different from existing prefab buildings (essentially just I-beams with connectors). The outer panels would all be identical (roof, wall, floors) made from stamped sheet metal or molded reinforced polymer, and they nest like bowls for efficient transport. Special panels with unique geometry would be needed for edges and corners.

So essentially you can build the entire pressure vessel using only 4 different unique parts (plus fasteners). And this pressure vessel can be have any X x Y x Z dimension that's an integer multiple of the grid size, without needing a factory re-tooling to make thicker and larger diameter cylinders and domes. This is nice for mission flexibility, repairability, simplicity, payload cost, and ease of eventual in-situ production.

There's two main challenges I see: reliably sealing all those joints, and setup labor. Conceivably this could be solved by some combination of assembly robots and self-deploying design.

After viewing your references, I believe what you are proposing in the “Amazing Martian Habitats” thread is different from what is intended in this thread.. What You suggest are large structures that require time to construct and that will accommodate 1000’s of people. This thread is intended to help with the first landings, to quickly set up structures for a few dozen to 100’s of people. These are the baby steps towards more expansive plans.

For example, if Starships were the first modular structures (as shawn in Reply #29) and we also used their O2/fuel tanks as inter-module hallways, we would dig a simple layout of shallow trenches such as shown below. Habs and greenhouse would be laid into the trenches and joined together. We would use the excavated regolith to cover over the layout of modules. After a few dozen landings and expansion of this pattern we could accommodate a few hundred people.