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Introduction

In the 2010 to 2020 time frame and beyond, NASA proposes to carry out international human missions to planetary bodies such as Mars (a mission of at least 600 days) with no crew rotation or resupply efforts. Such a mission is well beyond today's technical capabilities. Advances are needed in a variety of technical areas to improve reliability and reduce risk, equipment weight, power requirements, and costs.

As a partner in the Human Exploration and Development of Space (HEDS) Enterprise, NASA's Office of Life and Microgravity Sciences and Applications (OLMSA) seeks to increase space system and mission capabilities by accelerating the incorporation of biology-based advanced technology into both crewed and uncrewed exploration missions. Such technologies could help make current space systems more like biological systems —e.g., “smarter,” smaller, self-repairing—and might include, for example, electronic “noses” capable of emulating or enhancing human sensory capabilities, bio-based sensors for detecting radiation damage, insect-like robots for inspecting crevices, and self-repairing systems and materials.

CHARGE AND APPROACH

To help guide its activities OLMSA requested that the Space Studies Board organize an initial workshop to identify areas in biology-based technology research that appear to hold special promise for carrying biological science into technology directly applicable to space exploration. The workshop, held on October 21-22, 1997, at the Center for Advanced Space Studies in Houston, Texas, opened with a plenary session at which a number of NASA's mission and technology managers described their current visions of scenarios and technology needs for near-term HEDS missions. The remaining two sessions focused on identifying areas in biology-based research with a potential for (1) enhancing human well-being in space exploration and (2) enhancing human presence and function in space exploration. These two sessions were



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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration 1 Introduction In the 2010 to 2020 time frame and beyond, NASA proposes to carry out international human missions to planetary bodies such as Mars (a mission of at least 600 days) with no crew rotation or resupply efforts. Such a mission is well beyond today's technical capabilities. Advances are needed in a variety of technical areas to improve reliability and reduce risk, equipment weight, power requirements, and costs. As a partner in the Human Exploration and Development of Space (HEDS) Enterprise, NASA's Office of Life and Microgravity Sciences and Applications (OLMSA) seeks to increase space system and mission capabilities by accelerating the incorporation of biology-based advanced technology into both crewed and uncrewed exploration missions. Such technologies could help make current space systems more like biological systems —e.g., “smarter,” smaller, self-repairing—and might include, for example, electronic “noses” capable of emulating or enhancing human sensory capabilities, bio-based sensors for detecting radiation damage, insect-like robots for inspecting crevices, and self-repairing systems and materials. CHARGE AND APPROACH To help guide its activities OLMSA requested that the Space Studies Board organize an initial workshop to identify areas in biology-based technology research that appear to hold special promise for carrying biological science into technology directly applicable to space exploration. The workshop, held on October 21-22, 1997, at the Center for Advanced Space Studies in Houston, Texas, opened with a plenary session at which a number of NASA's mission and technology managers described their current visions of scenarios and technology needs for near-term HEDS missions. The remaining two sessions focused on identifying areas in biology-based research with a potential for (1) enhancing human well-being in space exploration and (2) enhancing human presence and function in space exploration. These two sessions were

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration organized to emphasize, respectively, (1) life support, habitat systems, and human health; and (2) perception, manipulation and locomotion, cognition, and systems and computation. In the absence of immediate access to information about past NASA research in these areas, session 1 and 2 discussions were based on first principles. In addition, because NASA's presentations outlined overall needs and the current thinking about system design for a future Mars mission and other generalized missions, few details were available to session participants concerning requirements at the system level, design criteria for important subsystems, or functional requirements for astronauts. Participants thus sought to identify basic areas of need and discussed creative ways in which biological concepts such as those listed in Box 1.1 might be applied to improve long-duration human exploration of space. Box 1.1 Biological Concepts with Potential Applications for Space Exploration Examples from biomimetics, the science of developing synthetic systems based on information obtained from biological systems, include manipulators that improve dexterity or grip, insect-like robots, neural networks, and recyclable adhesives such as barnacle-based glues. Examples of the application of biometaphorics principles of function and architecture inspired by life-unique properties include self-replicating systems, self-repairing structures and materials, ecological principles (e.g., critical trace materials seeded in spaceborne structural materials as future resources), and artificial life (e.g., self-organizing principles, self-assembling systems). Biomolecular materials incorporate biological molecules or concepts in nonbiological devices or systems or are structured in a way that is characteristic of biological materials. Examples include living cells used as sensors and clothing patterned after sharkskin. Hybrid organisms consist of genetically engineered biological components linked to nonbiological systems. Examples might include biological cells and computer chips (biochips) used in combination to detect radiation, genetically engineered beetles for carrying sensors, root-like plants that can creep into cracks and pores and grow as depositors of sealant, or surface penetration instruments (e.g., tentacle-like micro- or nano-sized probes). The following section summarizes the presentations by NASA personnel in the workshop's plenary session. Chapter 2 and Chapter 3 summarize the results of discussions by the participants in sessions 1 and 2, respectively. Chapter 4 offers some brief observations by workshop participants on points for consideration in any follow-on activities to further explore areas of biology-based research with the potential to enhance human exploration of space. Biographical sketches of the workshop's steering group are given in Appendix A, and information on the agenda and a list of participants are provided in Appendix B. In considering optimal use of technology to enable human exploration of space, it is worth noting that there are valid reasons to use physicochemical systems rather than less proven ones with biological elements. One reason is the increase in reliability that comes from using a proven technology rather than a new one for which failure modes have yet to be fully identified. The issue of reliability is important for “biology-based” systems, many of which interact in an as yet poorly defined chemical domain. By contrast, the interactions among mechanical systems are more amenable to complete systems identification and analysis. Methods will have to be

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration developed to evaluate the reliability of biology-based systems, a subject that is outside the scope of this report. NASA PRESENTATIONS NASA managers presented their current thinking about system design for a future Mars mission and other generalized missions. These presentations addressed Mars mission planning, exploration technology requirements, risks associated with Mars missions, advanced habitat concepts, advanced life support, human-machine interfaces, robotics and automation, and information processing. Mars Mission Planning An overview of Mars mission planning was provided by Douglas R. Cooke, deputy manager for exploration of the Advanced Development Office and manager of the Johnson Space Center (JSC) Exploration Office. The planning effort combines the scientific search for the origin of life and the study of planetary evolution with human exploration of space. Detailed plans have been developed for a set of robot missions to Mars in 2001. In addition, significant planning has taken place for technology investments needed for eventual human missions. Basic requirements include adequate Earth-to-orbit lift capability (80 metric tons for large payload volumes) and highly efficient space propulsion systems. An autonomous base will have to be established on Mars and fuel will have to be made from in situ resources. Space suits will have to be lightweight enough to enable astronauts to work on the martian surface. High-bandwidth communication and data-storage capabilities will be needed; two-way communications between Earth and Mars currently take 40 minutes. Payload size and cost to launch must be reduced by the development of closed-loop life support systems, reductions in power requirements, and design of lightweight information systems and instruments using micro- and nano-electronics and system components. Maintaining the health and safety of crew members will require research on the effects of galactic cosmic radiation on humans, the long-term effects of zero gravity and reduced gravity, and advanced diagnostics and medical care of the crew. In addition, advanced technology is needed for habitat structures and closed-loop life support systems. Exploration Technology Requirements Bret G. Drake of the JSC Exploration Office noted that space transportation accounts for 50 to 75 percent of any mission cost. Transportation costs, now $8,000 to $12,000 per pound, need to be reduced to $1,000 per pound. Life-cycle costs need to be minimized by, for example, using the martian atmosphere rather than propulsion to reduce a vehicle 's orbit, and obtaining power from in situ Mars resources such as methanol (CH3OH), methane (CH4), or oxygen (O2).

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration NASA divides the key technologies to support human exploration of space into five thrust areas: human support, advanced space transportation, advanced space power, information and automation, and sensors and instruments. Examples of needs related to human support include the following: Protection against exposure to radiation. Systems that could predict solar radiation events would contribute substantially to crew health and safety. Such systems might include, for example, x-ray detectors, visible light imagers, sensors attached to habitats, and personal radiation-hazard monitors that, especially if used in conjunction with integrated medical databases, could improve crew safety. Research is needed to understand the effects on biological systems of the deep-space radiation environment. Portable, high-resolution diagnostic systems are needed to detect injury arising from exposure to radiation. Advanced life support systems. To significantly reduce the consumables that must be taken on long-duration missions, ALS systems are needed for closed-loop air and water processing, solid waste processing, thermal control, and food production. Advanced “intelligent” technologies are needed to monitor and control such ALS systems. In addition, advances in structural concepts and lightweight materials are needed to enable the design of large habitats for transit to Mars and exploration of the planet's surface. Key technology thrusts include habitat concepts and emplacement methods (e.g., emplacement by robots), novel structural concepts (e.g., inflatable rather than traditional hard structures), and integrated protection against the effects of radiation. Systems to support extravehicular activity. Routine exploration of the surface of Mars will require advanced EVA suits and short- and long-range surface rovers that are dexterous, mobile, and sensitive to sensory and tactile input. Technologies that will contribute to these systems include advanced materials that enhance mobility and dexterity while maximizing protection against radiation and punctures; lightweight batteries that recharge rapidly; efficient, lightweight thermal-control systems; means for storing consumables, including cryogenic backpacks; humidity control; advanced sensors for monitoring O2, carbon dioxide (CO2), nitrogen (N2), temperature, and other environmental parameters; and advanced avionics such as heads-up displays. Environmental and medical monitoring. Miniature, highly sensitive sensors and instruments are needed to detect fire, toxins, and radiation; to monitor the state of food, air, and water; and to monitor human health. Systems for emergency medicine, telemedicine, and global monitoring and hazard avoidance (e.g., for protection against dust storms) are also needed. Miniaturized biotelemetry sensors and systems are needed for medical monitoring and portable clinical laboratory diagnostics. Robotics. Advanced robotics systems are needed to enhance mission safety, efficiency, and return by performing routine or complicated tasks prior to, and in conjunction with, the work done directly by astronauts. Systems of interest include those enabling dexterous manipulation

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration for scientific field work, subsurface sampling, locomotion, and assembly and construction activities on the surface of Mars. Risks Associated with Mars Missions An effort to identify the risks associated with a human mission to Mars was described by Charles Sawin, assistant to the director of the Space and Life Sciences Directorate for Science Payloads. A total of 105 risk factors for shuttle, low-Earth-orbit, lunar, and exploration missions are being tallied, and the activities necessary to support such missions are being ranked. Issues under consideration include spacecraft habitability, maintenance of crew health, effects of exposure to radiation, adaptation of humans to microgravity, psychological problems associated with long-term isolation and interpersonal tensions, and working in space and on planetary bodies. The risk factors will be validated by the National Space Biomedical Research Institute. The primary product of this activity—a road map that identifies the research required to mitigate the identified risk(s), the time frame in which the research needs to be accomplished, and the funding levels required—was scheduled to be available in January 1998. Technology needs in four categories were described: advanced miniaturization, “intelligent” systems, sensors and instruments, and human support. High-priority technologies for human support include those for preserving food and extending its shelf life for up to 5 years, nonintrusive monitoring of performance, data collection for crew training and development, training evaluation for ability to perform critical tasks, and waste recycling. Advanced Habitat Concepts Advanced habitat concepts were described by Kriss Kennedy, space architect in the Advanced Development Office of JSC. Three types of habitats of increasing levels of sophistication are envisioned: preintegrated hard-shell modules for deployment prior to the crewed mission; prefabricated (i.e., inflatable) structures for automated assembly on the surface of Mars; and structures made of indigenous martian resources as well as components from Earth, for example, underground habitats constructed with a tunneling or mining mole system to protect against radiation and provide a thermally stable environment. The planetary habitats will have to be lightweight, reliable, and easy to maintain. They might embody a number of biological concepts, such as artificial intelligence capabilities for self-analysis (i.e., to detect failure) and self-repair, and might feature “living” shells: micro-life-support systems embedded in the habitat skin, for example, to process carbon dioxide into oxygen or grow new matrix material to repair punctures.

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration Advanced Life Support Among the technical objectives discussed by Donald Henninger, chief scientist and deputy program manager for the Advanced Life Support program, was development of ALS system technologies that can significantly reduce life-cycle costs, improve operational performance, promote self-sufficiency, and minimize the expenditure of resources for missions of long duration. For example, resource recycling and processing and contaminant control systems need to be designed and integrated into other systems. These systems need to be optimized to provide for air and water revitalization in connection with the growth of crop plants. Efficient, reliable thermal control systems are needed to ensure heat acquisition, transport, and dissipation. Fully regenerative, integrated technologies are needed to recover air, water, food, and resources from waste. Issues related to performance in hypogravity must be resolved. Predictive models of fluid and fluid-gas behavior and interactions in hypogravity on the planetary surfaces are needed for use in the design of new ALS hardware, particularly for gravity-sensitive ALS components and subsystems (e.g., membranes). The performance of bioregenerative systems needs to be characterized at lunar and martian gravities; ultimately, it must match the performance achieved by such systems on Earth in terms of productivity, control, and predictability. ALS technology challenges for missions to the moon and Mars include water recovery from wastewater (e.g., by using multifiltration, reverse osmosis, iodine disinfection); control of CO2 levels (e.g., by using electrochemicals, sorbents, plants, enzymes); real-time air and water quality monitoring (e.g., by using lightweight, durable, low-power sensors); solid-waste processing and resource recovery (e.g., by using bioreactors, supercritical water oxidation); in situ recovery of useful gases from planetary resources; low-power, high-efficiency sources of light for plant growth; and system monitoring, command, and control. Several tests to integrate biological and physiochemical systems have been conducted by NASA at the Johnson Space Center's integrated life-support systems test facility. One test, done to verify the performance of biological and revitalization life support systems, involved an astronaut spending 15 days in a variable-pressure growth chamber. It has been estimated that at least a 10-square-meter plant-growing area would be needed to provide oxygen and carbon dioxide uptake for one person. In the test, nearly 11 square meters of wheat was successfully grown as a complement and backup to other life support systems; changes in gas concentration were observed with small changes in light intensity. In a second NASA test, four persons spent 30 days in a facility designed to verify the performance of physicochemical life support systems for air and water recycling. A 60-day test with four test subjects evaluated the integrated life support systems baseline for the International Space Station in the spring of 1997, and a three-month test was initiated in September 1997, verifying the performance of both biological subsystems and physicochemical systems for life support. Plants and a CO2 scrubber and CO2 reduction units were used for air revitalization along with a catalytic oxidizer for control of trace gas contaminants. A bacterial bioreactor for recovery of water was used in combination with physicochemical components to recycle all the water. An advanced thermal control subsystem was tested along with an automated system monitoring and control subsystem.

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration Human-Machine Interfaces Human-machine interfaces were discussed by James Maida, technical director for the Graphics Research and Analysis Facility, Lighting Evaluation and Test Facility, and Anthropometry and Biomechanics Facility in the JSC Flight Crew Support Division. Because of the isolation and long duration of a mission to Mars, human factors need to drive decisions about the use of resources. Three issues are critical: maintenance of the crew's physical and cognitive performance, provision of access to information for meeting contingencies and problem solving, and maintenance of crew performance by ensuring comfortable living conditions. Human-machine interface devices must be lightweight, small, and durable. Head-mounted displays need to be designed that offer high resolution, ease of use, and multipurpose applications for virtual and augmented vision (i.e., magnification, dynamic overlays, synthetic vision). Such displays could be used for flight control, maintenance, and teleconferencing. Biotelemetry and haptic feedback devices offering a sense of touch could be very useful. Natural language (i.e., voice) processing and comprehension systems would greatly enhance human-computer interactions. Information systems will need to be portable, fully integrated, and operable using voice commands. Robotics and Automation Automation technology needs were outlined by Jon D. Erickson, chief scientist for automation, robotics, and simulation at the JSC. As a permanent human presence is established farther and farther from Earth's surface and orbit, additional support systems will be needed that can provide safe, reliable, low-cost, high-performance transportation, construction, use of in situ resources, and closed-loop life support. These systems must be far better than the current state of the art. Robotics and automation technologies are in the early stages of development for in-orbit as well as extra- and intravehicular activity, and for interplanetary and planetary surface applications. They are being designed for operation and maintenance of spacecraft, surface systems deployment, operation and maintenance of energy generation and distribution systems, fuel generation and storage, regenerative life support (both physicochemical and biological), medical research and operations, surface vehicles, and human-robot teams. They can perform routine tasks while astronauts apply their energy to tasks requiring perception, judgment, creativity, and flexibility. A genetic architecture designed for monitoring and control in NASA 's integrated life-support systems test facility has three layers of intelligence. The top layer consists of simulation-and model-based reasoning for high-level goal setting and planning. The middle layer uses shared and traded control to execute tasks. The third layer is the skill manager, which provides situational awareness with natural-language understanding and generation. In another NASA project, a two-armed, mobile, sensate robot has been designed as a crew and habitat helper. It is similar to the armless robots currently used in some hospitals to deliver pharmaceuticals.

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Report of the Workshop on Biology-based Technology to Enhance Human Well-being and Function in Extended Space Exploration Additional research is needed on sensors (e.g., microelectrical mechanical systems [MEMS]), machine perception, and the transfer between humans and machines of information gained from situational awareness. Information Processing Information processing needs were described by Robert T. Savely, chief scientist of the Information Processing Directorate. NASA will need a full-spectrum supercomputing environment consisting of high-speed processors, mass storage, high-performance networks, and visualization hardware and software for extended space exploration by humans. For example, high-performance graphics hardware and software could enable the analysis and display of data in real time, so that multiple users could simultaneously have access to information and quickly identify new patterns and relationships among complex data. DNA computing, cellular engineering, and living neuronal nets could provide the basis for ultracomputers. Hybrid interfaces might be used to combine biological materials with silicon-based computation. The Defense Advanced Research Projects Agency (DARPA) work on ultrascale computing may suggest biological concepts that would be useful in information processing on NASA missions. For example, swarm computing, parallel computing, and quantum computing may lead to the design of materials that “think.” DARPA's projects on DNA computing involve the development of technologies for performing computations at the molecular level. Those on cellular engineering exploit bioengineering of one-celled organisms for computation and low-cost manufacturing of computational elements. The neural networks projects involve the in vitro growth of neuronal materials to synthesize neural networks that interface directly with electronic circuits.