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The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.

A dynamic simulation of the ISS CDRA hardware was created using the Aspen Custom Modeler software platform. The dynamic model calculates the material and energy balances that describe the system properties. The model was calibrated by comparison to test data results from a flight-like CDRA at NASA Marshall Space Flight Center. While other FORTRAN models of the CDRA already exist, developing an ACM simulation is the first step towards creating a generic tool to simulate larger collections of life support hardware. The ACM tool should make it possible to be very flexible when rearranging these models to simulate possible configurations of the life support subsystems that could be used in the future, especially for advanced life support applications.

An experimental study has been made of compressible jet mixing in an axisymmetric ejector of converging-diverging geometry. Three different jet sizes, 0.01, 0.0235, and 0.045 in. diameter were tested with three different mixer sizes, 0.25, 0.286, and 0.36 in. diameter. Jet and mixer combination were tested along with varying jet to mixer distances. The jet pressure varied from 20 to 200 psig, jet mass varied from 0.3 lbm/hr to 10 lbm/hr., and jet temperature varied from 21 to 24 deg. F. The secondary loop pressure varied from 3.7 to 25 psia, secondary mass flow varied from 1 to 70 lbm/hr, secondary loop pressure drop varied from 4 inH20 to 10 inH20, and secondary loop temperature varied same as jet temperature. The mass flow ratio was in the range of 2 to 14. The results were analyzed and compared with the Hickman and Nuckols and Sexton prediction models. The loss factor in Nuckols and Sexton model was adjusted to match the test results.

Significant system efficiency gains can be achieved in high-performance aircraft via a unitized structure that reduces parts count. For instance, reduced parts count leads to substantial engineering logistic cost savings through higher levels of subsystem and mounting hardware integration. It also creates performance benefits by eliminating structural connections. Residual stress management, however, remains a major obstacle to capturing full benefits and broadening the application of unitized structure solutions. This paper describes how Alcoa and others are developing tools to overcome limitations in current testing, evaluation, and design practices attributed to residual stress effects. The authors present recent advancements in fracture toughness and fatigue crack growth characterization, along with a new, integrated approach for improved accounting of residual stress effects during fracture critical component design, manufacturing planning, and life management.

This paper reviews the evolution and current state of atmospheric monitoring on the International Space Station to provide context from which we can imagine a more advanced and integrated system. The unique environmental hazards of human space flight are identified and categorized into groups, taking into consideration the time required for the hazard to become a threat to human health or performance. The key functions of a comprehensive monitoring strategy for a closed ecological life support system are derived from past experience and a survey of currently available technologies for monitoring air quality. Finally, a system architecture is developed incorporating the lessons learned from ISS and other analogous closed life support systems. The paper concludes by presenting recommendations on how to proceed with requirements definition and conceptual design of an air monitoring system for exploration missions.

Total sample containment is an absolute requirement for Mars sample return missions, derived from the requirement to protect against uncontrolled introduction of potentially hazardous foreign material into the earth's biosphere. These constraints of planetary protection comprise one of the major remaining hurdles to low cost implementation of sample return missions. It is suggested here that to spread the costs of the program, the first mission should consider sterilizing the samples and canister surfaces while still in space during the return to Earth.

The Carbon Dioxide Removal Assembly (CDRA) on board the International Space Station (ISS) has experienced periodic check valve and selector valve failures as a result of a gradual build-up of contamination from particles that have breeched the adsorbent bed seals. The current software that controls CDRA has limitations that make troubleshooting the unit difficult in these situations, in large part due to the fact that valve position telemetry is only available during certain times. There are also situations where it is required to perform operations manually that would benefit from added code logic and commands to facilitate these operations. The software has been reviewed for possible upgrades and changes that will allow engineers to better troubleshoot the unit in the event of various failures and also allow for better operability in degraded states.

The BIO-Plex facility will need to support a variety of life support system designs and operational strategies. These systems will be tested and evaluated in the BIO-Plex facility. An important goal of the life support program is to identify designs that best meet all size and performance constraints for a variety of possible future missions. Integrated human testing is a necessary step in reaching this goal. System modeling and analysis will also play an important role in this endeavor. Currently, simulation studies are being used to estimate air revitalization buffer and storage requirements in order to develop infrastructure requirements of the BIO-Plex facility. Simulation studies are also being used to verify that the envisioned operation strategy will be able to meet all performance criteria. In this paper, a simulation study is presented for a nominal BIO-Plex scenario with a high-level of crop growth.

Advancements in electrical, mechanical, and structural design onboard modern more electric aircraft have added significant stress to the thermal management systems (TMS). A thermal management system level analysis tool has been created in MATLAB/Simulink to facilitate rapid system analysis and optimization to meet the growing demands of modern aircraft. It is anticipated that the tracking of thermal energy through numerical integration will lead to more accurate predictions of worst case TMS sizing conditions. In addition, the non-proprietary nature of the tool affords users the ability to modify component models and integrate advanced conceptual designs that can be evaluated over multiple missions to determine the impact at a system level.

Texas colonias are unincorporated subdivisions characterized by inadequate water and wastewater infrastructure, inadequate drainage and road infrastructure, substandard housing, and poverty. Since 1989 the Texas Legislature has implemented policies to halt further development of colonias and to address water and wastewater infrastructure needs in existing and new colonias along the border with Mexico. Government programs and non-government and private organization projects aim to address these infrastructure needs. Texas Tech University's Water Resources Center demonstrated the use of alternative on-site wastewater treatment in the Green Valley Farms colonia, San Benito, Texas. The work in Green Valley Farms was a component of a NASA-funded project entitled “Evaluation of NASA's Advanced Life Support Integrated Water Recovery System for Non-Optimal Conditions and Terrestrial Applications.” Two households within the colonia were demonstration sites for the constructed wetlands.

In this investigation, analytical models were developed to predict the performance characteristics of axisymmetric single jet ejector. The ejector is divided into four parts, jet, mixer, nozzle, and diffuser. Basic flow equations were combined to calculate end to end flow characteristics for each of the four ejector components. Different jets and mixer combination were tested using three jet and three mixers. Characteristics curves have been drawn to predict flow characteristics of the ejector. Different configuration of jet and mixer incorporated different loss coefficient. Hence to get correct flow characteristics of the ejector right loss coefficient should be used.

The value of “ultracapacitors” (also referred to as “supercapacitors” or “electric double layer capacitors” in some literature) as an augmentation device when placed in parallel with “electrochemical” energy storage (i.e. battery) is presented in this paper. Since ultracapacitors possess unique attributes due to their higher value of energy storage density (or Joules/WattHrs per mass) compared to conventional capacitors while maintaining the peak power providing capability (to some degree) typical of conventional capacitors they may provide a near term solution in applications demanding longer battery operating life when placed in parallel. Such demands may be pronounced by the onset of More-Electric-Aircraft peak loads and “cold-crank” Auxiliary Power Unit (APU) electric-starting in demanding cold temperature environments.

Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in a high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. This paper describes preliminary results of a comparative experimental investigation into adsorbents for trace contaminant control. Ammonia sorbents and low temperature catalysts for CO oxidation are the foci. The data will be useful to designers of AR systems for Constellation. Plans for extended and repeated vacuum exposure of ammonia sorbents are also presented.

A method for capturing full-body scans for the purpose of extracting Extravehicular Activity (EVA) suit measurements is being evaluated. Subjects were marked using reflective spheres enabling researchers to acquire all 118 measurements of the suit sizing protocol. Several researchers measured the subjects using a full-body laser scanner, a motion analysis system, and standard anthropometrical equipment. The linear scanner measurements were compared to the motion analysis data, while the circumferential scanner measurements were compared to the manual data. The mean percent difference between the scanner measurements and motion analysis linear/manual circumferential measurements was 4.21%. It was concluded that the scanner measurements were accurate enough for preliminary sizing of EVA suits.

Spacecraft hardware trade studies compare options primarily on mass while considering impacts to cost, risk, and schedule. Historically, other factors have been considered in these studies, such as reliability, technology readiness level (TRL), volume and crew time. In most cases, past trades compared two or more technologies across functional and TRL boundaries, which is an uneven comparison of the technologies. For example, low TRL technologies with low mass were traded directly against flight-proven hardware without consideration for requirements and the derived architecture. To provide for even comparisons of spacecraft hardware, trades need to consider functionality, mission constraints, integer vs. real number of flight hardware units, and mass growth allowances by TRL.

This paper describes the development of a lead free, high temperature ceramic capacitor material having the base composition of (Na0.5 Bi0.5) TiO3. The goal is to modify this structure to create a material that has the relative permittivity of barium titanate with extended X7R-like properties to 250°C - an X14R. After an extensive compositional and theoretical modeling investigation a composition was selected and capacitors developed. The dielectric has a 1-kHz relative permittivity of ∼1200 with <±15% variation from -25 to +250°C and <5% loss from -55 to +250°C. These capacitors also have very low voltage coefficients, indeed they are positive at the low end of the temperature range, resulting in a combined TC-Vc capacitance variation 0%/-25% of nominal from -55 to +200°C with applied voltage stress from 20 to 260 V/mil.

The Centrifuge Accommodation Module (CAM) will be the home of the fundamental biology research facilities on the International Space Station (ISS). These facilities are being built by the Biological Research Project (BRP), whose goal is to oversee development of a wide variety of habitats and host systems to support life sciences research on the ISS. The habitats and host systems are designed to provide life support for a variety of specimens including cells, bacteria, yeast, plants, fish, rodents, eggs (e.g., quail), and insects. Each habitat contains specimen chambers that allow for easy manipulation of specimens and alteration of sample numbers. All habitats are capable of sustaining life support for 90 days and have automated as well as full telescience capabilities for sending habitat parameters data to investigator homesite laboratories.

A preliminary assessment of the reach envelope and field of vision (FOV) for a subject wearing a Mark III space suit was requested for use in human-machine interface design of the Science Crew Operations and Utility Testbed (SCOUT) vehicle. The reach and view of two suited and unsuited subjects were evaluated while seated in the vehicle using 3-dimensional position data collected during a series of reaching motions. Data was interpolated and displayed in orthogonal views and cross-sections. Compared with unsuited conditions, medio-lateral reach was not strongly affected by the Mark III suit, whereas vertical and antero-posterior reach were inhibited by the suit. Lateral FOV was reduced by approximately 40° in the suit. The techniques used in this case study may prove useful in human-machine interface design by providing a new means of developing and displaying reach envelopes.

The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. For these missions several food provisioning strategies are being investigated. Individual, prepackaged meals may be provided throughout the mission or commodities may be taken in bulk and processed while on the planetary surface. To enable these different supply scenarios, a packaging system must be developed that will protect the food or commodity and have minimal impact on system mass. Metric values for a prepackaged scenario and a bulk supply scenario, using current packaging material technologies, were compared. The results of this comparison show that bulk packaging penalties will potentially be more than an order of magnitude less than those of a prepackaged food system.

The earliest Digital Human Modeling systems were non-interactive analysis packages with crude graphics. Next generation systems added interactivity and articulated kinematic human models. The newest systems use real-time computer graphics, deformable figures, motion controllers, and user interfaces. Our long-term goal is to free the user as much as possible from interactive human model manipulation through direct understanding and execution of task instructions. We present a next generation DHM testbed that includes a scriptable interface, real-time collision-avoidance reach, empirical joint motion models, a versatile locomotion engine, motion capture and synthetic motion blends and combinations, and a smooth skinned scalable human model.