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New Generation NASA Robotsby Erin B. Patterson

ITH THE SPACE ShuttleDiscovery’s mission com-pleted in August, NASA’ssuccessful return to flightmarked an important first

step in its vision for space exploration asoutlined by President George W. Bush lastyear. The goal of that vision, the agencysays, is to embark on a journey that willtake humans back to the moon, eventuallyto Mars, and possibly beyond.

A primary component in fulfilling itsvision requires NASA to conduct re-search and develop technologies to an-swer many unknowns and solvechallenges of human inhabitation beyondlow-Earth orbit.

The agency has said it plans to send alunar-orbiter mission to the moon’s sur-face by 2008. Robotic landers are targetedto launch in 2009 or 2010, and NASA hopesto have astronauts return to the moon asearly as 2015 and no later than 2020. Toreach its goals, researchers must firststudy the lunar environment and assessits resources—resources that may be es-sential to human survival and robotic ex-ploration technologies on the lunar surfaceand then on Mars.

USING WHAT’S AVAILABLEOne component in ensuring survival is in-situ resource utilization (ISRU), which ex-ists to evaluate and exploit availableresources on the moon and Mars. As part ofNASA’s human systems research and tech-nology program, the idea behind ISRU isto leverage available resources and usethem to reduce cost and risk to humans dur-ing future exploration missions to the moonand Mars. In addition to ISRU, the human systems researchand technology program also is looking at non-human-relatedareas to reduce cost and risk.

Ronald A. Schlagheck, [Florida Alpha ’67] ISRU elementlead at Marshall Space Flight Center, compares the imple-mentation of ISRU for future exploration missions to ourearly colonial settlers: “When our ancestors came to America,they couldn’t bring all their resources with them. So they hadto utilize what was on the land for food and other supplies.The concept was that you have to leverage off what you haveto make the next step.”

The vision for exploration’s success hinges upon thisconcept, says Raymond French, project manager for ISRUat Marshall. “If we’re going to make this exploration ini-tiative long-term, or even permanent, we’re going to haveto rely on indigenous, natural resources.”

According to NASA, extracting materials from the indig-enous environment is a necessity for less expensive, longer-term missions to the moon and Mars. The agency believesISRU is critical for space exploration with regard to mass,cost and risk reduction, flexibility, space commercialization,and sustained human presence in space.

The LRO will orbit the moonto make measurements for futurerobotic and human landing sites.

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In the initial ISRU process, NASA plans to excavate lu-nar regolith, which is the layer of rock and soil material onthe moon’s surface. With these extracted resources, life sup-port gases such as oxygen, other inert gases, water—if itexists in one form or another—and metals can be produced.In addition, regolith materials, researchers say, will be use-ful in propellants manufacturing, radiation shielding, spare-parts manufacturing, and power generation.

Indigenous resources will be an important means of en-ergy production to propel a vehicle from one planetary bodyto another in future exploration missions beyond the moon,Schlagheck said. “When you’re further out in the solar sys-tem, you need a method to use resources for transportationto the next place you’re going.”

ROBOTS PRECEDE PEOPLEBy identifying processes that will support humans and tech-nologies on long-term missions, NASA hopes to be well onits way to creating a human presence on Mars, and evenbeyond. And the agency plans for robotics systems to playa large role in its first steps on that journey.

NASA is implementing its robotic lunar exploration pro-gram through Goddard Space Flight Center, which will con-duct robotic missions to land, orbit, and operate on the moonto pave the way for human exploration. The program is in-tended to develop new approaches and technologies to sup-port exploration.

In late 2008, the agency plans to launch its Lunar Re-connaissance Orbiter (LRO), said to be the first spacecraftbuilt as part of the vision for space exploration. Accordingto Goddard, the orbiter “will facilitate returning men safelyto the moon where testing and preparations for an even-tual manned mission to Mars will be undertaken.”

The LRO will orbit the moon to make measurements forfuture robotic and human landing sites. It also will identifypotential lunar resources and better characterize the moon’senvironment and its biological impacts, including radiation,dust, and partial gravity. According to NASA, the LRO willbe equipped with exotic instruments to survey the moon’ssurface and its resources. They include the:

• Lunar orbiter laser altimeter measurement investiga-tion, which determines the topography of the lunar surface,measuring landing site slopes and searching for polar ice inshadowed regions;

• Lunar reconnaissance orbiter camera, which receivestargeted images of the lunar surface, pinpointing possiblelanding site hazards;

• Lunar exploration neutron detector, which maps theflux of neutrons from the lunar surface to search for evi-dence of ice and provides measurements of the space radia-tion environment;

• Diviner lunar radiometer experiment, which maps thetemperature of the entire lunar surface to identify cold-trapsand potential ice deposits;

• Lyman-alpha mapping project, which observes thelunar surface in the far ultraviolet. The system searchesfor surface ices and frosts in polar regions and provides im-ages of permanently shadowed regions illuminated only bystarlight; and

• Cosmic ray telescope for the effects of radiation, whichcharacterizes the global lunar radiation environment andits biological impacts.

The LRO also will contain a propulsion module and aninstrument module for electrical, mechanical, and thermaltechnologies that make up part of the orbiter’s spacecraft.Its spacecraft also will contain a solar array system and anantenna system.

The orbiter is scheduled to fly for one Earth year in a30-50 km circular, polar orbit. According to Goddard, thismay be followed by an extended mission of up to five yearsin a low-maintenance orbit that allows continued observa-tions and possibly the use of the LRO as a communicationrelay satellite.

ISRU will play a large part in the LRO mission, withmany of its instruments designed to study the location andmakeup of materials on the moon that can be manufacturedto support long-term exploration missions.

After the launch of the LRO, the robotic lunar explora-tion program will forge ahead by launching follow-up mis-sions that more closely involve ISRU, characterizing lunarregolith for resource use and identifying potential waterresources in polar regions.

DIGGING UP DIRTOne of the primary goals in ISRU work is developing ameans to extract necessary materials from the moon’s re-sources, but just how do researchers and engineers plan todo it?

Actually, some of the extraction techniques and processesmay not be much different from mining and refining tech-niques used on Earth. In fact, NASA is considering severaltechnologies that currently exist in terrestrial mining ap-plications.

Although some ideas are more established than others,“most technologies that we’re looking at are an extrapola-tion of what we’ve already got here on Earth,” French said.

Looking at it this way, extracting materials from lunarregolith is similar to mining ore on Earth. However, thereare some alterations that must be made to existing miningtechnologies to fit the lunar and Martian environments be-cause, in those environments, “efficiency and effectivenessbecomes more and more important,” French said.

As a result, engineers are looking to adapt the existingterrestrial mining methods, as well as new techniques, tothe lunar and/or Martian environments.

And for researchers, the environment itself can pose sev-eral obstacles that engineers need to consider when devis-ing a method for excavation.

“In the lunar environment,” French said, “reduced grav-ity can be a hurdle with regard to handling granular mate-rials. And developing engineering techniques to deal withthe way those materials behave is a challenge.”

With the one-sixth of Earth’s gravity that exists on themoon, soil particles disturbed by different factors can taketime to settle. In addition, the lunar regolith itself is a cohe-sive, angular material that can create a challenge not onlyin terms of settling, but also in packing, making the soil dif-ficult to handle, French said.

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Studying the makeup of lunar regolith using returnedApollo samples and developing larger quantities of artificialregolith, referred to as simulant materials, here on the groundbefore actual missions also is a significant component of ISRUresearch. With the help of Johnson Space Center in Houston,French said researchers have developed simulant materialsusing samples gathered from previous lunar missions. Re-searchers are able to use those materials to study the makeupof lunar regolith, create an effective excavation technology,and better understand its components and behavior.

NASA will use what it learns in robotic and human mis-sions to the moon as validation to take its next step—goingto Mars. French said that researchers at the Jet PropulsionLaboratory, which builds unmanned spacecraft including theMars rovers, are discussing working with ISRU researchersat Marshall to develop simulant materials for Martian soil.

REPLACING WHAT’S LOSTWith the knowledge it gains from future robotic missions,NASA hopes to develop technologies that support long-termspace exploration. But on sustained missions, researchersand engineers also must consider the possible failure of cer-tain technologies and parts and the need for additional sup-port for those parts. The agency has said it plans to usein-situ fabrication and repair (ISFR) to reduce resourcerequirements, spare parts inventory, and, like ISRU, en-hance mission safety while decreasing mass and cost.

According to NASA, ISFR provides a contingency planthat includes developing technologies through which newtools can be manufactured and repair techniques can be car-ried out in space.

Fabrication technologies are one sub-element of ISFR.These technologies provide a means of building new partsor replacing existing parts or tools for vehicle or habitatequipment. The new materials may include those deliveredfrom Earth or fabricated in-situ such as metals, plastics,ceramics, and composites.

Repair and non-destructive evaluation (NDE) technolo-gies are another ISFR sub-element. They are meant to pro-vide a means of repairing systems during transport andwhile on the moon and Mars.

According to NASA, NDE technologies will be devel-oped from existing techniques to support repair processes,the initial fabrication and assembly of in-situ habitats andstructures, and replacement parts. NDE technologies willdevelop self healing techniques for wire insulation and com-posite repairs, as well as other techniques for electrical com-ponent repair. Researchers plan to develop welding andpatching or bonding techniques for other repair processes.

Repair and NDE technologies will reduce the need foradditional parts through the use of in-situ, imported, andrecycled materials. Repairs are considered a cheaper, bet-ter, and faster mode of function, according to NASA. Be-cause radiation poses a threat to long-term survival inspace environments, habitat structures that incorporatein-situ resources provide options for autonomous, afford-able, pre-positioned habitat environments with radiationshielding features and protection from micrometeoritesand exhaust plumes.

Erin B.Pattersonis a copy editorfor Bizjournals,a network ofonline businesspublicationsbased in Char-lotte, NC. Shereceived abachelor’s degreein Spanish and

journalism from Auburn University in 2001 and amaster’s degree in journalism from the University ofMemphis in 2003. A member of Kappa Tau Alphahonor society, Erin previously worked as anoutreach coordinator for NASA’s space partnershipdevelopment program.

The ISFR habitat structures sub-element focuses on thedevelopment of lunar and Martian structures with environ-mental protection features made mostly of in-situ resourcesand deployed with a high degree of automation. The use ofin-situ resources to manufacture habitat structures or en-hancing pre-existing structures instead of using pre-fabri-cated structures would greatly reduce mass-liftingrequirements, according to the agency.

NASA plans for habitat structures to investigate sixstructural categories based on in-situ materials. They in-clude raw regolith; blocks, which are carved rock or regolithconfigured into a habitat structure; reinforced concrete; thinfilms and inflatables, which are components constructed byinflation or assembled as liners in other structural elements;deployable metal structures, which are structures that workwith other components such as regolith or inflatables; andglass products, which are elements or components fabri-cated from regolith-based glass.

VISION FOR THE FUTUREIn the next two decades, NASA will develop suites of tech-nologies and fly missions that it believes will play instru-mental roles in carrying out its vision for space exploration.

According to the agency, robotic and human explorationof the moon will improve existing capabilities, creating along-term presence on Mars and possibly throughout thesolar system. NASA also hopes its vision will help createcommercial and industrial applications for use in terrestrialapplications.

With a tentative date set for the first orbital robotic mis-sion to the moon, the agency will take another step towardthe goals outlined in its vision; a vision that it says will con-tinue to expand the knowledge and change the lives ofpeople on Earth.