Lunar Rock Transportation & Processing

Corey Harmon ASTE 527 Final Project December 15, 2008

Current NASA Plan for Lunar ISRU

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ESAS Architecture includes pre-cursor missions to demonstrate ISRU capabilities

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Crew support includes O 2 and H 2 O production from lunar regolith

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Ascent vehicles designed to be compatible with ISRU-derived propellants

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Extraction of metals from regolith to produce items like solar arrays

Image: NASA •

What’s missing – a focus on simple construction using raw materials!

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Surface Composition at Mons Malapert

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The main base at Mons Malapert is located in the lunar highlands

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Surface is covered with ancient “rubble” called breccia, which are angular rock fragments resulting from impacts

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Rocks are igneous (similar to granite) and are rich in calcium and aluminum

Image: Lunar surface (http://www.le.ac.uk/ph/faulkes/web/planets/r_pl_moon.html) Dec 15, 2008 Image: Close-up of Feldspar mineral (Wikipedia) CH - 3

Construction Techniques

Sintering Cast Basalt Sulfur Concrete Dry-Packing Needs small grain sizes (less than 400 um) and high temperatures (1,100 deg C) Involves full melting of regolith to shape into blocks and tiles Sulfur is extracted from the regolith and melted to create concrete slabs Stones are cut and fit against each other without mortar or gluing material.

Image: Pyramids at Giza (Wikipedia) •

For the first crewed missions to the lunar surface, the available technology will limit the complexity of structures

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Ancient civilizations were able to do much more with much less – we can do the same on the moon!

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Material Collection and Transportation

To build landing pads and roads, the surface must be cleared and leveled

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Rocks collected by the equipment with basket-type scoop Rocks are placed in transport cars strung along tether line

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A tether system has several benefits over a rover

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Rovers can spend time collecting material, not hauling it back and forth

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Fewer mechanisms that are exposed to the damaging lunar dust

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Tether system set-up around the perimeter of the landing site, road, and habitat sites

Habitat Image: Architecture and Vision Excavator Image: [2] Lander Image: [1] Dec 15, 2008 CH - 5

Processing & Shaping

Jaw Crusher Cone Crusher Horizontal Shaft Impactor (HIS) Vertical-Shaft Impactor (VSI) - Squeezes rocks between two ridged surfaces

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Squeezes rocks between an eccentrically gyrating spindle

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Impacts rocks with hammers that swing on a rotating shaft

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Can only be used on soft materials

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Rock is vertically projected against bed of pulverized rock and breaks along fracture planes

Image: Diagram of VSI (http://www.bgs.ac.uk/planning4minerals/Resources_21.htm) • •

VSI Crusher

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Final output is cube-shaped aggregates

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Grade is determined by velocity of shaft – can be changed to create different sized aggregates

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Material is fed into vertical shaft from the top from transport cars Power provided by combination of batteries and solar power beaming

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Applications

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Rocks will be shaped for easy dry-packing

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Rocks fit together without need for mortar or gluing material

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What can be made?

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Base layers for landing pads, roads, etc.

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Shade walls and berms Exposed platforms or towers Unpressurized dome structures for storage Outer protection for inflatable habitats

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radiation shielding

Image: Collage of lunar surface and terrestrial retaining wall (wall image from spanishwhitevillages.com) Dec 15, 2008 Image: Example of unpressurized dome (CalEarth) CH - 7

Next Steps

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More active processing techniques

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Drill or cut away pieces from large outcrops and shape into slabs

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Larger and more stable structures can be built (slabs, blocks, bricks, columns, beams)

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Same methodology as ancient Egyptian’s used to build pyramids There may be issues with thermal control – need to get dissipate heat from drill or saw bits in vacuum environment

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Make sulfur concrete

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Requires processing of regolith to remove sulfur

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High heating needed to melt sulfur and regolith together to make concrete

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Concrete may not be very strong

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Rapid-prototyping using lunar regolith as sintering material

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Can make items for use in habitats, crewed vehicles, etc.

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May be able to replace failed components in some systems

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Can make geometrically complex objects with very few components

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References

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Connolly, John. Altair Lunar Lander Design. Presentation at 59 th International Astronautical Congress. Glasgow, October 2008.

Freitas, Robert A. Jr. Advanced Automation for Space Missions. Appendix 5D. NASA/ASEE Summer Study, 1980 Mendell, W. W., Editor. Lunar Bases and Space Activities of the 21st Century. Houston, TX, Lunar and Planetary Institute, 1985, Ch. 6.

Shrunk, David, et al. The Moon: Resources, Future Development, and Settlement. Praxis Publishing, 2 nd Edition, 2008.

Simon, Tom, et al. “NASA In-Situ Resource Utilization (ISRU) Development & Incorporation Plans.” Presentation at Technology Exchange Conference, Galveston, TX, November 2007.

Wilhelms, Don E. Geologic History of the Moon. U.S. Geological Survey Professional Paper, 1987.

NASA’s Exploration Systems Architecture Study: Final Report. NASA-TM-2005-214062, November 2005.

http://www.synapses.co.uk/astro/moon3.html

“Lunar Mare” Wikipedia article.

“Egyptian Pyramid Construction Techniques” Wikipedia article “Rock Crusher” Wikipedia article

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BACKUP MATERIAL

Dec 15, 2008

Apollo & Luna Sample

Element

Oxygen Silicon Aluminum Iron Calcium

Composition

Lunar Highland Lunar Lowland Earth Issues

446,000 210,000 133,000 48,700 417,000 212,000 69,700 132,000 466,000 277,000 81,300 50,000 Highlands rich Lowlands rich Highlands rich

Applications

Fuel propellant, life support Glasses, ceramics, etc. Solar cells.

Electrical conductor, structures, mirrors Structural steel Ceramics, electrical conductor 106,800 78,800 36,300

Sodium Potassium Magnesium Titanium Hydrogen Phosphorus Manganese Carbon Chlorine Chromium

3,100 800 45,500 3,100 56 500 675 100 17 850 2,900 1,100 57,600 31,000 54 660 1,700 100 26 2,600 28,300 25,900 20,900 4,400 1,400 1,050 950 200 130 100 adequate?

Chemical processing adequate?

Chemical processing lunar rich lunar poor Metal alloying element High strength metal Fuel propellants, life, chem. proc.

lunar poor lunar has Metal alloys CH - 11

Pros & Cons of Using Lunar Rocks as Construction Material

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PROS

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Rocks are abundantly available

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Low lunar gravity results in easier handling and the structures can be taller, more slender, and longer than on Earth

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They are not susceptible to the harsh lunar environment

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CONS

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Processing must be done in a controlled environment to prevent high-energy debris from escaping

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Adaptation of terrestrial processors needs significant testing

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