Author Topic: SpaceX's Martian Underground  (Read 16627 times)

Online envy887

  • Full Member
  • ****
  • Posts: 1555
  • Liked: 670
  • Likes Given: 370
Re: SpaceX's Martian Underground
« Reply #20 on: 01/12/2017 08:05 PM »
The cutter above is often used to cut an arched tunnel, like a quonset hut, but there are other heads used for profile cutting such as squaring off.  There are vertical versions for boring shafts.

The head motors are hydraulic, so power can be whatever you can run the pump with; electric, or an IC using ISRU methalox. Possibly alcohol + GOX using a different ISRU process.
Gah, combustible fuels in an engine are just TERRIBLE if you're doing ISRU. They use about an order of magnitude more power (wasting like 90% of the energy) than electric, and since you have to bring along oxygen (and usually want to reclaim the water in the exhaust), usually don't even end up lighter even compared to battery power.

I wish that idea would just die.

Particularly for mining equipment that's not moving fast or far. All it needs is an extension cord.  ;D

Online Robotbeat

  • Senior Member
  • *****
  • Posts: 25730
  • Minnesota
  • Liked: 5830
  • Likes Given: 4325
Re: SpaceX's Martian Underground
« Reply #21 on: 01/12/2017 08:27 PM »
Just stating the options. I agree with electric, unless you're boring some distance from high power generation. You're not going to carry a reactor or 200 m^2 of panels around. Solid oxide fuel cells maybe...
A good lithium ion battery actually trades very well when you have to carry the oxygen with you.

And actually, solar panels are easy to place remotely.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline sanman

  • Senior Member
  • *****
  • Posts: 3336
  • Liked: 360
  • Likes Given: 1
Re: SpaceX's Martian Underground
« Reply #22 on: 01/14/2017 05:36 AM »
Cutters work well enough, as long as whatever you're boring through is solid enough to be self supporting..

Otherwise you may need a boring machine with shield and have to erect  support ribs/marscrete behind you.  At least not too much water to deal with.. depending on where you're going..

If Musk were to use some kind of microwave drill thing to bore tunnels with, perhaps it could also microwave-sinter together the material forming the walls of the tunnel, to make it more self-supporting.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 5864
  • Germany
  • Liked: 1434
  • Likes Given: 1147
Re: SpaceX's Martian Underground
« Reply #23 on: 01/14/2017 07:01 AM »
If Musk were to use some kind of microwave drill thing to bore tunnels with, perhaps it could also microwave-sinter together the material forming the walls of the tunnel, to make it more self-supporting.

When Elon Musk goes into tunneling, as he is claiming, then I expect some novel method used. I strongly doubt that he would start a company using conventional boring heads. On earth those heads or at least the cutting implements are exchanged very frequently for wear. It would be very advantageous to have a method that reduces need of maintenance. On earth and much more so on Mars.

Offline sanman

  • Senior Member
  • *****
  • Posts: 3336
  • Liked: 360
  • Likes Given: 1
Re: SpaceX's Martian Underground
« Reply #24 on: 01/14/2017 10:49 AM »
When Elon Musk goes into tunneling, as he is claiming, then I expect some novel method used. I strongly doubt that he would start a company using conventional boring heads. On earth those heads or at least the cutting implements are exchanged very frequently for wear. It would be very advantageous to have a method that reduces need of maintenance. On earth and much more so on Mars.

I agree he'd probably have some disruptive technological approach in mind. I'm thinking Microwave Drilling could be a candidate, because it could work well for off-world usage too. Microwave Drilling doesn't need heavy hundred-ton rotorheads, which would suffer wear and tear, and need replacement. It would be lighter in mass, and would work on fungible energy supply, and save on the need for replacement parts from Earth.

It would also be a logical progression for colonization technology, after developing the big transport rocket.

But just regarding the idea of microwave-sintering your tunnel walls/roof right there in-situ, is that something that might be feasible/worthwhile?

Offline Bob Shaw

  • Full Member
  • ****
  • Posts: 938
  • Liked: 328
  • Likes Given: 321
Re: SpaceX's Martian Underground
« Reply #25 on: 01/14/2017 12:11 PM »
I think Musk may consider developing drilling using rocket technology (also a possibility for power generation using MHD). There are already torpedoes which 'drill' through water using forward-facing rocket motors.

Offline Rocket Science

  • Senior Member
  • *****
  • Posts: 7561
  • Maker of physicists and engineers…
  • Liked: 1951
  • Likes Given: 4460
Re: SpaceX's Martian Underground
« Reply #26 on: 01/14/2017 12:51 PM »
Explosives are "crude but  effective"... ;) Plus it provides a form of entertainment while Elon is perhaps building the first Martian Movie Multiplex.. ;D.
“The laws of physics are unforgiving”...
Rob

Offline TripD

  • Full Member
  • ****
  • Posts: 434
  • Waiting to hitch out on the next F9R
  • Liked: 331
  • Likes Given: 222
Re: SpaceX's Martian Underground
« Reply #27 on: 01/14/2017 11:21 PM »
Explosives work well, but drilling those holes would imo require manpower vs. automation.  Drills get frequently stuck badly in holes and can require a frustrated artistry to remove.

Offline lamontagne

  • Full Member
  • ****
  • Posts: 848
  • Liked: 1025
  • Likes Given: 194
Re: SpaceX's Martian Underground
« Reply #28 on: 01/14/2017 11:53 PM »
Well, I was thinking there was the mining/ISRU aspect to this as well. Perhaps a tunneling machine would eventually evolve into a mining machine, which could extract ore and maybe even feed it into a smelter.


The article shows a large-sized machine as the current state of the art, but there's no reason that a smaller machine couldn't be used to bore large tunnels, if it had the right technology. I was thinking that microwave boring machine could be small enough and light-weight enough to be transportable to Mars, where it could be used to bore much larger cavities - although using the microwave approach for extracting ore might take some re-thinking (maybe with microwaves you could somehow bore and smelt at the same time?)


And at the same time, a microwave-based approach might offer the chance to disrupt the marketplace and take business from the higher-cost established players.

We've been going over this on the Amazing martian habitat thread.  You might want to check out the discussion.

Here is a visual of what I think might be an underground colony made with roadheaders adapted to Mars.  It is largely based on personal experience with mining garages in the Canadian north.

Hope you enjoy!

As far as microwave sintering goes, it may not go deep enough.  There appears to be calcium carbonate on Mars, so my proposal is to put the base near to a deposit and use it to make concrete to line the walls.
« Last Edit: 01/14/2017 11:55 PM by lamontagne »

Offline lamontagne

  • Full Member
  • ****
  • Posts: 848
  • Liked: 1025
  • Likes Given: 194
Re: SpaceX's Martian Underground
« Reply #29 on: 01/14/2017 11:57 PM »
Explosives work well, but drilling those holes would imo require manpower vs. automation.  Drills get frequently stuck badly in holes and can require a frustrated artistry to remove.

Explosives are just a form of energy.  On Mars they would probably need to be made from atmospheric nitrogen, and in some sense eventually come from solar energy.  So might as well use the solar energy directly to drive equipment.  Bringing the explosives from Earth would likely be too expensive.

Online Robotbeat

  • Senior Member
  • *****
  • Posts: 25730
  • Minnesota
  • Liked: 5830
  • Likes Given: 4325
Re: SpaceX's Martian Underground
« Reply #30 on: 01/15/2017 02:13 AM »
No way. Just mix liquid carbon monoxide (or, if you want it closer to oxyliquit as used on Earth, reduce the CO/CO2 all the way to carbon) and liquid oxygen.

We used to use it for mining on Earth all the time, and has already been used for Mars exploration (well, in FICTION :) ).
https://en.wikipedia.org/wiki/Oxyliquit

No water required, no fancy chemistry. In fact, we're sending a CO/O2 ISRU device to Mars for testing on the 2020 rover, so the chemistry will be demonstrated very soon.
« Last Edit: 01/15/2017 02:14 AM by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline TripD

  • Full Member
  • ****
  • Posts: 434
  • Waiting to hitch out on the next F9R
  • Liked: 331
  • Likes Given: 222
Re: SpaceX's Martian Underground
« Reply #31 on: 01/15/2017 03:27 AM »
Explosives work well, but drilling those holes would imo require manpower vs. automation.  Drills get frequently stuck badly in holes and can require a frustrated artistry to remove.

Explosives are just a form of energy.  On Mars they would probably need to be made from atmospheric nitrogen, and in some sense eventually come from solar energy.  So might as well use the solar energy directly to drive equipment.  Bringing the explosives from Earth would likely be too expensive.

I was not promoting bringing explosives from earth.  I was bringing up the issue of having to drill many holes for any type of explosive.  Rocks chip and pin the bit quite frequently.  You literally have to outsmart the bit from time to time to retrieve it because shear torque will not work.

Offline KelvinZero

  • Senior Member
  • *****
  • Posts: 3209
  • Liked: 370
  • Likes Given: 81
Re: SpaceX's Martian Underground
« Reply #32 on: 01/15/2017 09:01 AM »
I was wondering if laser boring for the holes to place oxyliquit within might be a good trade on mars where using more power and simplicity of operation might be preferable to having to replace more parts that would be cheap on earth but dominated by cost/kg on mars, and also cost of labour

I did find one possibly legitimate hit on the topic. It was hard for me to tell how legitimate it was.
http://www.mining.com/web/lasers-the-future-of-mining/

Offline sanman

  • Senior Member
  • *****
  • Posts: 3336
  • Liked: 360
  • Likes Given: 1
Re: SpaceX's Martian Underground
« Reply #33 on: 01/15/2017 10:41 AM »
Is there a safety/risk issue in manufacturing and using explosives on Mars for mining purposes? Or would that all be done by robots anyway? (including placement of explosives)

By contrast, controllable machinery like a road-header or its laser/microwave equivalent might seem a little safer and less risky.




Offline gurucr7.fc

  • Member
  • Posts: 1
  • Liked: 0
  • Likes Given: 0
Re: SpaceX's Martian Underground
« Reply #34 on: 01/15/2017 10:52 AM »
Too much exiting

Sent from my LS-4005 using Tapatalk


Offline Lumina

Re: SpaceX's Martian Underground
« Reply #35 on: 01/15/2017 11:18 AM »
A NASA report I read argues that the optimal source of ISRU water is granular surface regolith which has a 1% to 3% water content almost everywhere on Mars between latitudes 0-50N.

If this is how water production will go, then there is synergy in processing the 97% to 99% regolith already in hand to isolate minerals and metals.

If tunnels are excavated to produce habitats then the tailings from the excavation could also be processed for ISRU of water and minerals in the same system that processes the loose surface regolith.

So based on the above, it might not be worth the time and maintenance effort to excavate tunnels just for ISRU mining. The tunnels would also have to serve a habitat purpose to make economic sense.

Offline TripD

  • Full Member
  • ****
  • Posts: 434
  • Waiting to hitch out on the next F9R
  • Liked: 331
  • Likes Given: 222
Re: SpaceX's Martian Underground
« Reply #36 on: 01/15/2017 05:10 PM »
A system set up to process fine grains would have a tough time dealing with  chunks of rocks from mine tailings.  I just remembered the simplicity of those old stamp mills.  They could turn those rocks into powder.  ;)

Offline lamontagne

  • Full Member
  • ****
  • Posts: 848
  • Liked: 1025
  • Likes Given: 194
Re: SpaceX's Martian Underground
« Reply #37 on: 01/16/2017 12:13 AM »
Explosives work well, but drilling those holes would imo require manpower vs. automation.  Drills get frequently stuck badly in holes and can require a frustrated artistry to remove.

Explosives are just a form of energy.  On Mars they would probably need to be made from atmospheric nitrogen, and in some sense eventually come from solar energy.  So might as well use the solar energy directly to drive equipment.  Bringing the explosives from Earth would likely be too expensive.

I was not promoting bringing explosives from earth.  I was bringing up the issue of having to drill many holes for any type of explosive.  Rocks chip and pin the bit quite frequently.  You literally have to outsmart the bit from time to time to retrieve it because shear torque will not work.
I was just agreeing that it was not a good idea to bring them from Earth.  I'm curious as to what is more cost effective, creating in-situ explosives, using solar power, probably solar electricity, or mechanical mining using electricity.

Offline sanman

  • Senior Member
  • *****
  • Posts: 3336
  • Liked: 360
  • Likes Given: 1
Re: SpaceX's Martian Underground
« Reply #38 on: 01/17/2017 01:05 AM »
There are some places like Hellas Basin where the Martian crust is supposed to be much thinner (10km), and deeper lying rock strata have been exposed.

What kind of depth would have to be tunneled to, in order to support liquid water?

Offline Rocket Science

  • Senior Member
  • *****
  • Posts: 7561
  • Maker of physicists and engineers…
  • Liked: 1951
  • Likes Given: 4460
Re: SpaceX's Martian Underground
« Reply #39 on: 01/17/2017 01:15 AM »
With a 3D Solar Sinter you could print your own shelter and possible avoid the need for tunneling out a shelter...

“The laws of physics are unforgiving”...
Rob

Tags: