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Dava J Newman - One of the best experts on this subject based on the ideXlab platform.
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mission enhancing capabilities for science driven exploration Extravehicular Activity derived from the nasa basalt research program
Planetary and Space Science, 2020Co-Authors: Kara H Beaton, Dava J Newman, Jeffrey A Hoffman, Steven P Chappell, Alex Menzies, Victor Luo, So Young Kimcastet, Johannes Norheim, Eswar Anandapadmanaban, Stewart P AbercrombieAbstract:Abstract The NASA-funded Biologic Analog Science Associated with Lava Terrains (BASALT) program is investigating candidate Mars Extravehicular Activity (EVA) concepts of operations and capabilities through science-driven terrestrial fieldwork under Mars-mission operational constraints. The third BASALT field test consisted of ten simulated EVAs in the Kilauea Caldera and Kilauea Iki regions of Hawai’i in November 2017. Each EVA included two Extravehicular (EV) crewmembers completing real (non-simulated) geobiochemical science objectives (e.g., collecting detailed imagery and scientific instrument data and extracting samples of basalt for further laboratory investigations), two intravehicular crewmembers who supported the EV crew in real-time, and a Mission Support Center comprised of remote scientists and operators who provided scientific expertise during the EVAs across Mars-relevant communication latencies. Throughout this field test, a series of new capabilities, including high-resolution panoramic imagery, mobile automated light detection and ranging data, immersive mixed-reality terrain models, and augmented-reality field systems for terrain navigation and annotation, were incorporated and evaluated during the mission simulation for their ability to enable and enhance science. The value provided by these capabilities was assessed using a variety of objective and subjective technology impact metrics, including detailed EVA task timing data, space-to-ground interaction data, and heritage subjective assessments of capability assessment (a measure of the potential for mission enhancement), simulation quality (a measure of simulation fidelity), and acceptability (including the specification of desired, warranted, and required improvements). In general, these capabilities were rated at least moderately enhancing for future planetary EVA, meaning that they are likely to moderately enhance one of more aspects of EVA or significantly enhance EVA on rare occasions. A number of specific improvements to these capabilities were identified, which warrant further development and testing, and several complementary future studies are proposed. Together, these data provide critical knowledge to help meet design challenges associated with future science-driven planetary EVA. While this paper specifically focuses on applications for future human spaceflight exploration, many of the results and lessons learned are also applicable to present-day terrestrial scientific fieldwork.
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Exoskeleton energetics: Implications for planetary Extravehicular Activity
2017 IEEE Aerospace Conference, 2017Co-Authors: Christopher E. Carr, Dava J NewmanAbstract:Humans first visited another world nearly 50 years ago and are poised to return to the Moon and visit Mars in the coming decade(s). Developing a space suit that supports safe, efficient, and effective exploration despite the extremes of temperature, pressure, radiation, and environmental hazards like dust and topography remains a critical challenge. Space suits impose restrictions on movement that increase metabolic rate and limit the intensity and duration of Extravehicular Activity. In this study, a lower body exoskeleton was used to test a simple model that predicts the energy cost of locomotion across gait and gravity. Energetic cost and other variables were measured during treadmill locomotion, with and without a lower body exoskeleton, in simulated reduced gravity and in Earth gravity. Six subjects walked and ran at constant Froude numbers, non-dimensional parameters used to characterize gait. The springlike energy recovery of the exoskeleton legs was estimated using energetics data in combination with the model. Model predictions agreed with the observed results (no statistical difference). High spring-like energy recovery of the exoskeleton legs lowered measures of the energetic cost of locomotion. For planetary Extravehicular Activity, our work reveals potential approaches to optimizing space suits for efficient locomotion, for example, tuning the stiffness and spring-like energy recovery of space suit legs.
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morphing compression garments for space medicine and Extravehicular Activity using active materials
Aerospace medicine and human performance, 2016Co-Authors: Bradley T Holschuh, Dava J NewmanAbstract:Compression garments tend to be difficult to don/doff, due to their intentional function of squeezing the wearer. This is especially true for compression garments used for space medicine and for Extravehicular Activity (EVA). We present an innovative solution to this problem by integrating shape changing materials-NiTi shape memory alloy (SMA) coil actuators formed into modular, 3D-printed cartridges-into compression garments to produce garments capable of constricting on command.A parameterized, 2-spring analytic counterpressure model based on 12 garment and material inputs was developed to inform garment design. A methodology was developed for producing novel SMA cartridge systems to enable active compression garment construction. Five active compression sleeve prototypes were manufactured and tested: each sleeve was placed on a rigid cylindrical object and counterpressure was measured as a function of spatial location and time before, during, and after the application of a step voltage input.Controllable active counterpressures were measured up to 34.3 kPa, exceeding the requirement for EVA life support (29.6 kPa). Prototypes which incorporated fabrics with linear properties closely matched analytic model predictions (4.1%/-10.5% error in passive/active pressure predictions); prototypes using nonlinear fabrics did not match model predictions (errors >100%). Pressure non-uniformities were observed due to friction and the rigid SMA cartridge structure.To our knowledge this is the first demonstration of controllable compression technology incorporating active materials, a novel contribution to the field of compression garment design. This technology could lead to easy-to-don compression garments with widespread space and terrestrial applications.
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Morphing Compression Garments for Space Medicine and Extravehicular Activity Using Active Materials.
Aerospace medicine and human performance, 2016Co-Authors: Bradley T Holschuh, Dava J NewmanAbstract:INTRODUCTION: Compression garments tend to be difficult to don/doff, due to their intentional function of squeezing the wearer. This is especially true for compression garments used for space medicine and for Extravehicular Activity (EVA). We present an innovative solution to this problem by integrating shape changing materials-NiTi shape memory alloy (SMA) coil actuators formed into modular, 3D-printed cartridges-into compression garments to produce garments capable of constricting on command. METHODS: A parameterized, 2-spring analytic counterpressure model based on 12 garment and material inputs was developed to inform garment design. A methodology was developed for producing novel SMA cartridge systems to enable active compression garment construction. Five active compression sleeve prototypes were manufactured and tested: each sleeve was placed on a rigid cylindrical object and counterpressure was measured as a function of spatial location and time before, during, and after the application of a step voltage input. RESULTS: Controllable active counterpressures were measured up to 34.3 kPa, exceeding the requirement for EVA life support (29.6 kPa). Prototypes which incorporated fabrics with linear properties closely matched analytic model predictions (4.1%/-10.5% error in passive/active pressure predictions); prototypes using nonlinear fabrics did not match model predictions (errors >100%). Pressure non-uniformities were observed due to friction and the rigid SMA cartridge structure. DISCUSSION: To our knowledge this is the first demonstration of controllable compression technology incorporating active materials, a novel contribution to the field of compression garment design. This technology could lead to easy-to-don compression garments with widespread space and terrestrial applications.
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developing a spacesuit injury countermeasure system for Extravehicular Activity modeling and analysis
42nd International Conference on Environmental Systems, 2012Co-Authors: Allison P Anderson, A Diaz, M Kracik, Guillermo Trotti, Jeffrey A Hoffman, Dava J NewmanAbstract:Extravehicular Activity (EVA) is one of the most critical enabling capabilities for human spaceflight. Performing EVA is both technically challenging and physically demanding, requiring many hours of training and detailed preparation. As a result of working and training in the Extravehicular mobility unit (EMU) spacesuit, many astronauts sustain musculoskeletal and minor injuries. Although injuries are typically minor and self-limited, they have the potential to impact mission success. We outline our research methodology to investigate EVA injury ultimately providing solutions that can be implemented both in the EMU and in future spacesuit designs. We review the issues and mechanisms causing injury as documented in the literature. The result of this work will be an injury database with input from many NASA stakeholders. We also highlight our work to model the astronaut performing realistic EVA motions to study the interaction between the person and the suit. Spacesuit models of the EMU and Mark III spacesuits will be used in combination with a human body model driven by the biomechanics of EVA motions. We will investigate joint torque, muscle activation, and contact pressure between the body and suit. This modeling effort informs our spacesuit injury countermeasure designs and recommendations. We present our design process for protection devices that ameliorate current astronaut suitinduced injuries.
Cinda Chullen - One of the best experts on this subject based on the ideXlab platform.
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continued advancement of supported liquid membranes for carbon dioxide control in Extravehicular Activity applications
International Conference on Environmental Systems (ICES 2015), 2015Co-Authors: David T Wickham, Kevin J Gleason, Jeffrey R Engel, Scott W Cowley, Cinda ChullenAbstract:The development of a new, robust, portable life support system (PLSS) is a high priority for NASA in order to support longer and safer Extravehicular Activity (EVA) missions. One of the critical PLSS functions is maintaining the carbon dioxide (CO2) concentration in the suit at acceptable levels. Although the Metal Oxide (MetOx) canister has historically performed very well, it has a finite CO2 adsorption capacity. Therefore, the size and weight of the unit would have to be increased to extend EVA times. Consequently, new CO2 control technologies must be developed in order to meet mission objectives without increasing the size of the PLSS. Recent work has centered on sorbents that can be regenerated during the EVA; however, this strategy increases the system complexity and power consumption. A much simpler approach is to employ a membrane that vents CO2 to space and retains oxygen (O2). A membrane has many advantages over current technology: it is a continuous system with no limit on capacity, it requires no consumables, and it does not need any hardware to switch beds between absorption and regeneration. Unfortunately, conventional gas separation membranes do not have the needed selectivity for use in the PLSS. However, the required performance could be obtained with a supported liquid membrane (SLM), which consists of a microporous material filled with a liquid that selectively reacts with CO2 over O2. In a recently completed Phase II SBIR project, Reaction Systems, Inc. achieved the required CO2 permeance and selectivity with an SLM in a flat sheet configuration. This paper describes work to convert the SLM into a more compact form and to scale it up to handle more representative process flow rates.
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advanced supported liquid membranes for co2 control in Extravehicular Activity applications
International Conference on Environmental Systems (ICES 2014), 2014Co-Authors: David T Wickham, Kevin J Gleason, Jeffrey R Engel, Scott W Cowley, Cinda ChullenAbstract:Developing a new, robust, portable life support system (PLSS) is currently a high priority for NASA in order to support longer and safer Extravehicular Activity (EVA) missions. One of the critical PLSS functions is maintaining the carbon dioxide (CO2) concentration in the suit at acceptable levels. Although the Metal Oxide (MetOx) canister has worked well, it has a finite CO2 adsorption capacity. Consequently, the unit would have to be larger and heavier to extend EVA times. Therefore, new CO2 control technologies must be developed to meet mission objectives without increasing the size of the PLSS. Although recent work has centered on sorbents that can be regenerated during the EVA, this strategy increases the system complexity and power consumption. A simpler approach is to use a membrane that selectively vents CO2 to space. A membrane has many advantages over current technology: it is a continuous system with no theoretical capacity limit, it requires no consumables, and it requires no hardware for switching beds between absorption and regeneration. Unfortunately, conventional gas separation membranes do not have adequate selectivity for use in the PLSS. However, the required performance could be obtained with a supported liquid membrane (SLM), which consists of a micro porous material filled with a liquid that selectively reacts with CO2 over oxygen (O2). In a current Phase II SBIR project, Reaction Systems has developed a new reactive liquid, which has effectively zero vapor pressure making it an ideal candidate for use in an SLM. The SLM function has been demonstrated with representative pressures of CO2, O2, and water (H2O). In addition to being effective for CO2 control, the SLM also vents moisture to space. Therefore, this project has demonstrated the feasibility of using an SLM to control CO2 in an EVA application. 1 President
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Extravehicular Activity technology development status and forecast
41st International Conference on Environmental Systems, 2011Co-Authors: Cinda Chullen, David T WestheimerAbstract:Beginning in Fiscal Year (FY) 2011, Extravehicular Activity (EVA) technology development became a technology foundational domain under a new program Enabling Technology Development and Demonstration. The goal of the EVA technology effort is to further develop technologies that will be used to demonstrate a robust EVA system that has application for a variety of future missions including microgravity and surface EVA. Overall the objectives will be reduce system mass, reduce consumables and maintenance, increase EVA hardware robustness and life, increase crew member efficiency and autonomy, and enable rapid vehicle egress and ingress. Over the past several years, NASA realized a tremendous increase in EVA system development as part of the Exploration Technology Development Program and the Constellation Program. The evident demand for efficient and reliable EVA technologies, particularly regenerable technologies was apparent under these former programs and will continue to be needed as future mission opportunities arise. The technological need for EVA in space has been realized over the last several decades by the Gemini, Apollo, Skylab, Space Shuttle, and the International Space Station (ISS) programs. EVAs were critical to the success of these programs. Now with the ISS extension to 2028 in conjunction with a current forecasted need of at least eight EVAs per year, the EVA technology life and limited availability of the EMUs will become a critical issue eventually. The current Extravehicular Mobility Unit (EMU) has vastly served EVA demands by performing critical operations to assemble the ISS and provide repairs of satellites such as the Hubble Space Telescope. However, as the life of ISS and the vision for future mission opportunities are realized, a new EVA systems capability could be an option for the future mission applications building off of the technology development over the last several years. Besides ISS, potential mission applications include EVAs for missions to Near Earth Objects (NEO), Phobos, or future surface missions. Surface missions could include either exploration of the Moon or Mars. Providing an EVA capability for these types of missions enables in-space construction of complex vehicles or satellites, hands on exploration of new parts of our solar system, and engages the public through the inspiration of knowing that humans are exploring places that they have never been before. This paper offers insight into what is currently being developed and what the potential opportunities are in the forecast
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Extravehicular Activity technology needs
AIAA SPACE 2010 Conference & Exposition, 2010Co-Authors: David T Westheimer, Cinda ChullenAbstract:Extravehicular activities (EVAs) are an essential component of human space flight. Crewmembers wearing spacesuits have planted flags on the surface of the Moon, inspected the Space Shuttle’s thermal protection system, built the International Space Station, captured satellites, repaired the Hubble Space Telescope, and performed many other critical jobs. EVAs will continue to be required for human space flight. Whether future missions consist of building new space telescopes, exploring asteroids, returning to the surface of the Moon, or even visiting Mars, spacesuits will be a critical component of those missions. Over the past several years, NASA has seen significant progress in EVA system development as part of the Exploration Technology Development Program and the Constellation Program. EVA system components have typically been divided into three main systems: Pressure Garment System (PGS); Portable Life Support System (PLSS); and Power, Communications, Avionics, and Informatics (PCAI) System. The PGS contains all of the components that physically interface with the crewmember. These components include the gloves, bearings, helmet, and boots as well as the multiple layers of materials that make up the spacesuit itself. The PLSS performs the functions of thermal control, providing a pressurized oxygen environment, carbon dioxide (CO2) removal, and humidity control. The overall PLSS architecture, schematic, and packaging of the components also must be considered. The PCAI system performs the functions of power storage and delivery, communication and navigation, data acquisition and control, caution and warning, and information management. This paper provides a status on the corresponding technology development and discusses future needs for EVA system development.
Matthew J. Miller - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Decision Support Systems for Envisioned Human Extravehicular Activity Operations: From Requirements to Validation and Verification:
Journal of Cognitive Engineering and Decision Making, 2019Co-Authors: Matthew J. Miller, Karen M. FeighAbstract:This work presents the results of a laboratory-based study of prototype decision support systems (DSS) for envisioned human Extravehicular Activity (EVA). A central feature of this work is demonstr...
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decision support system requirements definition for human Extravehicular Activity based on cognitive work analysis
Journal of Cognitive Engineering and Decision Making, 2017Co-Authors: Matthew J. Miller, Kerry Mcguire, Karen M. FeighAbstract:The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as Extravehicular Activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the Extravehicular Activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.
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Extravehicular Activity operations concepts under communication latency and bandwidth constraints
2017 IEEE Aerospace Conference, 2017Co-Authors: Kara H Beaton, Matthew J. Miller, Andrew F J Abercromby, Steven P Chappell, Shannon Kobs Nawotniak, Scott S. Hughes, Allyson BradyAbstract:The Biologic Analog Science Associated with Lava Terrains (BASALT) project is a multi-year program dedicated to iteratively develop, implement, and evaluate concepts of operations (ConOps) and supporting capabilities intended to enable and enhance human scientific exploration of Mars. This paper describes the planning, execution, and initial results from the first field deployment, referred to as BASALT-1, which consisted of a series of ten simulated Extravehicular activities on volcanic flows in Idaho's Craters of the Moon National Monument and Preserve. The ConOps and capabilities deployed and tested during BASALT-1 were based on previous NASA trade studies and analog testing. Our primary research question was whether those ConOps and capabilities work acceptably when performing real (non-simulated) biological and geological scientific exploration under four different Mars-to-Earth communication conditions: 5 and 15 min one-way light time communication latencies and low (0.512 Mb/s uplink, 1.54 Mb/s downlink) and high (5.0 Mb/s uplink, 10.0 Mb/s downlink) bandwidth conditions, which represent two alternative technical communication capabilities currently proposed for future human exploration missions. The synthesized results, based on objective and subjective measures, from BASALT-1 established preliminary findings that the baseline ConOp, software systems, and communication protocols were scientifically and operationally acceptable with minor improvements desired by the “Mars” Extravehicular and intravehicular crewmembers. However, unacceptable components of the ConOps and required improvements were identified by the “Earth” Mission Support Center. These data provide a basis for guiding and prioritizing capability development for future BASALT deployments and, ultimately, future human exploration missions.
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operational assessment of apollo lunar surface Extravehicular Activity
2017Co-Authors: Matthew J. Miller, Austin Claybrook, Suraj Greenlund, Jessica J Marquez, Karen M. FeighAbstract:Quantifying the operational variability of Extravehicular Activity (EVA) execution is critical to help design and build future support systems to enable astronauts to monitor and manage operations in deep-space, where ground support operators will no longer be able to react instantly and manage execution deviations due to the significant communication latency. This study quantifies the operational variability exhibited during Apollo 14-17 lunar surface EVA operations to better understand the challenges and natural tendencies of timeline execution and life support system performance involved in surface operations. Each EVA (11 in total) is individually summarized as well as aggregated to provide descriptive trends exhibited throughout the Apollo missions. This work extends previous EVA task analyses by calculating deviations between planned and as-performed timelines as well as examining metabolic rate and consumables usage throughout the execution of each EVA. The intent of this work is to convey the natural variability of EVA operations and to provide operational context for coping with the variability inherent to EVA execution as a means to support future concepts of operations.
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plrp 3 operational perspectives conducting science driven Extravehicular Activity with communications latency
IEEE Aerospace Conference, 2016Co-Authors: Matthew J. Miller, Darlene S S Lim, A L Brady, Z Cardman, Ernest Bell, Brent W Garry, D Reid, Steve Chappell, Andrew F J AbercrombyAbstract:The Pavilion Lake Research Project (PLRP) is a unique program where a combination of scientific research and human space exploration concepts are integrated in an underwater spaceflight analog environment. The 2015 PLRP field season took place at Pavilion Lake, British Columbia, Canada, where science-driven exploration techniques focused on microbialite characterization and acquisition. These techniques were evaluated within the context of crew and robotic deep-space Extravehicular Activity (EVA) operations. The primary objective of this analog study was to detail the capabilities, decision-making processes, and operational concepts required to meet non-simulated scientific objectives during 5-minute one-way communication latency utilizing crew and robotic assets. The relationship and interaction between ground and flight crew was found to be dependent on the specific scientific activities being addressed. Furthermore, the addition of a second intravehicular operator was found to be highly enabling when conducting science-driven EVAs.
Kunihiko Tanaka - One of the best experts on this subject based on the ideXlab platform.
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superior mobility of knee parts with dual versus single axis hinge for Extravehicular Activity without prebreathing
Acta Astronautica, 2019Co-Authors: Kunihiko Tanaka, Tadaaki ManoAbstract:Abstract The current U.S. Extravehicular Activity (EVA) suit is pressurized at 0.29 atm, which creates a risk of decompression sickness (DCS). If higher mobility is acquired, higher inner pressure is allowed. We previously demonstrated a wider range of motion (ROM) with lower muscle force using an elastic glove pressurized at 0.65 atm compared with a nonelastic glove pressurized at 0.29 atm, which simulated the current U.S. EVA suit. Pressurization at 0.65 atm is the lowest pressure that avoids DCS without prebreathing. For larger joints, other restraint parts are needed to depress ballooning of the elastic material during pressurization. In the present study, we developed hard restraint parts for the knee joint covering the elastic garment for the lower limb, and compared the ROM and flexion force between a dual and single axis during pressurization at 0.65 atm. The joint motion and force required during flexing action were recorded. During flexion, the ROM was significantly larger and the peak force was significantly lower with the dual-than single-axis part. Thus, a dual axis of hard restraint part has higher mobility than a single axis during pressurization without a risk of DCS.
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self perspiration garment for Extravehicular Activity improves skin cooling effects without raising humidity
Acta Astronautica, 2014Co-Authors: Kunihiko Tanaka, Koji Nakamura, Tetsuro KatafuchiAbstract:Abstract Introduction The current U.S. Extravehicular Activity (EVA) suit in space includes liquid cooling and ventilation garment (LCVG) to control thermal condition. Tubes knitted in LCVG for flowing water interrupt evaporation of perspiration, and astronauts feel discomfort. In the present study, we hypothesized that a self-perspiration garment would effectively lower the skin temperature without raising humidity in the garment. Thus, we developed and examined the effects of the garment. Methods Eight healthy subjects were studied with a cyclic ergometer of 30, 60 90 and 120 W loading for 3 min each. Skin temperature and humidity on the back were measured continuously. Subjects wore and tested three types of garments i.e., a spandex wear without any cooling device (Normal), a simulated LCVG (s-LCVG) or the spandex wear knitted a vinyl tube for flowing water, and the spandex wear with a tube, which flows water and self-perspiration with oozing water for evaporative cooling (SPEC). Results All measurements were reached to steady state 2–3 min after the setting. The s-LCVG decreased skin temperature 0.39±0.14 °C during 12 min of cooling. With SPEC, skin temperature did not decrease significantly until 6–9 min after starting the cooling. However, the temperature decreased rapidly and significantly after that, and finally decreased 1.59±0.32 °C. Humidity in the SPEC was significantly lower than that in s-LCVG. Discussion SPEC was effective for lowering skin temperature without raising humidity in the garment. The concept is expected to use as a better cooling system during EVA.
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development and evaluation of a glove for Extravehicular Activity space suit without prebreathing
Journal of ergonomics, 2014Co-Authors: Kunihiko TanakaAbstract:The current United States space suit, called an Extravehicular mobility unit (EMU), is pressurized with 100% oxygen at 0.29 atm (4.3 psi or 29.6 kPa) in the vacuum of space. This pressure is much lower than that on the earth or in the International Space Station, and prebreathing is required to avoid decompression sickness (DCS). Higher pressure can reduce the risk of DCS, but mobility would be sacrificed due to larger pressure differential between the inside and outside of the suit. To solve the issues regarding mobility, we employed elastic material. If high mobility is acquired, higher pressurization can be employed. Thus, we developed an elastic glove pressurized at 0.65 atm, which is the minimal pressure to avoid decompression sickness without prebreathing. Range of motion with the nonelastic glove at 0.29 atm, which is simulated current EMU, was similar to that of the elastic glove at 0.65 atm. However, the required force evaluated by electromyography during finger flexion using elastic glove at 0.65 atm was smaller than that using the nonelastic glove at 0.29 atm. These results will encourage further development and investigation of a new Extravehicular Activity suit.
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mobility of an elastic glove for Extravehicular Activity without prebreathing
Aviation Space and Environmental Medicine, 2011Co-Authors: Kunihiko Tanaka, Mizuki Ikeda, Yosuke Mochizuki, Tetsuro KatafuchiAbstract:Introduction The current U.S. Extravehicular Activity (EVA) suit is pressurized at 0.29 atm, which is much lower than the pressures of sea level and inside a space station. Higher pressure can reduce the risk of decompression sickness (DCS), but mobility would be sacrificed. We have demonstrated that a glove and sleeve made of elastic material increased mobility when compared with those made of nonelastic material, such as that found in the current suit. We hypothesized that an elastic glove of 0.65 atm that has no risk of DCS also has greater mobility compared with a non-elastic glove of 0.29 atm. Methods The right hands of 10 healthy volunteers were studied in a chamber with their bare hands at normal ambient pressure, after donning a non-elastic glove with a pressure differential of 0.29 atm, and after donning an elastic glove with a pressure differential of 0.29 and 0.65 atm. Range of motion (ROM) of the index finger and surface electromyography (EMG) amplitudes during finger flexion were measured. Results ROM with gloves was significantly smaller than that of bare hands, but was similar between conditions of gloves regardless of elasticity and pressure differentials. However, EMG amplitudes with the elastic glove of 0.29 and 0.65 atm were significantly smaller than those with the non-elastic glove of 0.29 atm. Discussion The results suggest that mobility of the elastic glove of 0.65 atm may be better than that of the non-elastic glove of 0.29 atm, similar to that used in the current EVA suit.
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development and evaluation of gas pressurized elastic sleeves for Extravehicular Activity
Aviation Space and Environmental Medicine, 2010Co-Authors: Kunihiko Tanaka, Chikara Abe, Chihiro Iwata, Kenji Yamagata, Masao Tanaka, Nobuyuki Tanaka, Momoka Tohnan, Hironobu MoritaAbstract:INTRODUCTION: In space, mobility of the current Extravehicular Activity space suit is limited due to the pressure differential between the inside and outside of the suit. We have previously demonstrated that an elastic glove increased mobility when compared with a non-elastic glove such as that found in the current suit. Extending this work, we hypothesized that an elastic sleeve would also have more mobility compared to a non-elastic sleeve, but a partially elastic sleeve, consisting of elastic joints sewn to non-elastic parts in low mobility areas, might generate similar mobility to a wholly elastic sleeve. METHODS: The right arms of 10 volunteers were studied with wholly elastic, partially elastic, and non-elastic sleeves in a chamber pressure of -220 mmHg. Range of motion (ROM) of the wrist and electromyography (EMG) of the flexor carpi radialis muscle and the biceps brachii muscle during wrist and elbow flexion were measured. RESULTS: ROM of the wrist was similar among all the sleeves. However, EMG amplitudes during wrist flexion with both elastic sleeves were significantly smaller than that with the non-elastic sleeve. EMG amplitudes during 90 degrees of elbow flexion were also significantly smaller in both elastic sleeves. However, no significant difference in EMG amplitudes was observed between the two elastic sleeves (0.53 +/- 0.06, 0.56 +/- 0.07, 1.14 +/- 0.10 V for wholly elastic, partially elastic, and non-elastic sleeves, respectively). DISCUSSION: The mobility of elastic sleeves is better than that of a non-elastic sleeve. Elasticity over the joints is important; however the elasticity of the other parts does not appear to affect mobility.
Karen M. Feigh - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Decision Support Systems for Envisioned Human Extravehicular Activity Operations: From Requirements to Validation and Verification:
Journal of Cognitive Engineering and Decision Making, 2019Co-Authors: Matthew J. Miller, Karen M. FeighAbstract:This work presents the results of a laboratory-based study of prototype decision support systems (DSS) for envisioned human Extravehicular Activity (EVA). A central feature of this work is demonstr...
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decision support system requirements definition for human Extravehicular Activity based on cognitive work analysis
Journal of Cognitive Engineering and Decision Making, 2017Co-Authors: Matthew J. Miller, Kerry Mcguire, Karen M. FeighAbstract:The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as Extravehicular Activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the Extravehicular Activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.
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operational assessment of apollo lunar surface Extravehicular Activity
2017Co-Authors: Matthew J. Miller, Austin Claybrook, Suraj Greenlund, Jessica J Marquez, Karen M. FeighAbstract:Quantifying the operational variability of Extravehicular Activity (EVA) execution is critical to help design and build future support systems to enable astronauts to monitor and manage operations in deep-space, where ground support operators will no longer be able to react instantly and manage execution deviations due to the significant communication latency. This study quantifies the operational variability exhibited during Apollo 14-17 lunar surface EVA operations to better understand the challenges and natural tendencies of timeline execution and life support system performance involved in surface operations. Each EVA (11 in total) is individually summarized as well as aggregated to provide descriptive trends exhibited throughout the Apollo missions. This work extends previous EVA task analyses by calculating deviations between planned and as-performed timelines as well as examining metabolic rate and consumables usage throughout the execution of each EVA. The intent of this work is to convey the natural variability of EVA operations and to provide operational context for coping with the variability inherent to EVA execution as a means to support future concepts of operations.
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preliminary work domain analysis for human Extravehicular Activity
Human Factors and Ergonomics Society International Annual Meeting (HFES 2015), 2015Co-Authors: Kerry Mcguire, Matthew J. Miller, Karen M. FeighAbstract:A work domain analysis (WDA) of human Extravehicular Activity (EVA) is presented in this study. A formative methodology such as Cognitive Work Analysis (CWA) offers a new perspective to the knowledge gained from the past 50 years of living and working in space for the development of future EVA support systems. EVA is a vital component of human spaceflight and provides a case study example of applying a work domain analysis (WDA) to a complex sociotechnical system. The WDA presented here illustrates how the physical characteristics of the environment, hardware, and life support systems of the domain guide the potential avenues and functional needs of future EVA decision support system development.
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Information flow model of human Extravehicular Activity operations
2015 IEEE Aerospace Conference, 2015Co-Authors: Matthew J. Miller, Kerry Mcguire, Karen M. FeighAbstract:Future human spaceflight missions will face the complex challenge of performing human Extravehicular Activity (EVA) beyond the low Earth orbit (LEO) environment. Astronauts will become increasingly isolated from Earth-based mission support and thus will rely heavily on their own decision-making capabilities and onboard tools to accomplish proposed EVA mission objectives. To better address time delay communication issues, EVA characters, e.g. flight controllers, astronauts, etc., and their respective work practices and roles need to be better characterized and understood. This paper presents the results of a study examining the EVA work domain and the personnel that operate within it. The goal is to characterize current and historical roles of ground support, intravehicular (IV) crew and EV crew, their communication patterns and information needs. This work provides a description of EVA operations and identifies issues to be used as a basis for future investigation.
