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This project investigates methods to capture an astronaut's exhaled carbon dioxide (CO2) before it becomes diluted with the high volumetric oxygen flow present within a space suit. Typical expired breath contains CO2 partial pressures (pCO2) in the range of 20-35 mm Hg (.0226-.046 atm). This research investigates methods to capture the concentrated CO2 gas stream prior to its dilution with the low pCO2 ventilation flow. Specifically this research is looking at potential designs for a collection cup for use inside the space suit helmet. The collection cup concept is not the same as a breathing mask typical of that worn by firefighters and pilots. It is well known that most members of the astronaut corps view a mask as a serious deficiency in any space suit helmet design. Instead, the collection cup is a non-contact device that will be designed using a detailed Computational Fluid Dynamic (CFD) analysis of the ventilation flow environment within the helmet.

With the increasing emphasis on Systems Engineering, there is a need to ensure that Electrical/Electronic (E/E) Systems Endurance Testing of vehicles, in a real world environment, prior to Production Launch, is performed in a manner and at a technological level that is commensurate with the high level of electronics and computers in contemporary vehicles. Additionally, validating the design and performance of individual standalone electronic systems and modules “on the bench” does not guarantee that all the permutations and combinations of real-world hardware, software, and driving conditions are taken into account. Traditional Proving Ground (PG) vehicle testing focuses mainly on powertrain durability testing, with only a simple checklist being used by the PG drivers as a reminder to cycle some of the electrical components such as the power window switches, turn signals, etc.

The Advanced Integration Matrix (AIM) will design a ground-based test facility for developing revolutionary integrated systems for joint human-robotic missions in order to study and solve systems-level integration issues for exploration missions beyond Low Earth Orbit (LEO). This paper describes development plans for educational outreach activities related to technological and operational integration scenarios similar to the challenges that will be encountered through this project. The education outreach activities will provide hands-on, interactive exercises to allow students of all levels to experience design and operational challenges similar to what NASA deals with everyday in performing the integration of complex missions. These experiences will relate to and impact students' everyday lives by demonstrating how their interests in science and engineering can develop into future careers, and reinforcing the concepts of teamwork and conflict resolution.

This paper summarizes a study on axle balance measurement and balancing strategies. Seven types of axles were investigated. Test samples were randomly selected from products. Two significant development questions were set out to be answered: 1) What is the minimum rotational speed possible in order to yield measured imbalance readings which correlated to in-vehicle imbalance-related vibration. What is the relationship between the measured imbalance and rotational speed. To this end, the imbalance level of each axle was measured using a test rig with different speeds from 800 to 4000 rpm with 200 rpm increments. 2) Is it feasible to balance axle sub-assemblies only and still result in a full-assembly that satisfies the assembled axle specification? To this end, the sub-assemblies were balanced on a balance machine to a specified level. Then with these balanced sub-assemblies, the full assemblies were completed and audited on the same balance test rig in the same way.

Knowledge of the loads experienced by a leaf spring suspension is required for the optimal design of the suspension components and frame. The most common method of representing leaf springs is the SAE 3 link model, which does not give good results in the lateral direction. In this paper, a beam element leaf spring model is developed. This model is validated using data obtained from laboratory tests done on leaf spring assemblies. The model is then subjected to actual road load data measured on the Proving Ground. Lastly, results from the beam element model are presented and compared with results obtained from proving ground tests. Overall, the beam element model gives good results in all directions except in situations where it is subjected to high fore/aft acceleration and high reverse braking events.

As a key component in its ground test bed capability, NASA's Advanced Life Support Program has been developing a large-scale advanced life support facility capable of supporting long-duration testing of integrated bioregenerative life support systems with human test crews. This facility, the Bioregenerative Planetary Life Support Systems Test Complex (BIO-Plex), is currently under development at the Johnson Space Center. The BIO-Plex is comprised of a set of interconnected test chambers with a sealed internal environment capable of supporting test crews of four individuals for periods exceeding one year. The life support systems to be tested will consist of both biological and physicochemical technologies and will perform all required air revitalization, water recovery, biomass production, food processing, solid waste processing, thermal management, and integrated command and control functions.

Mode management is an essential part of the design process for NVH performance. System resonances must be sufficiently separated to minimize interaction from source inputs and each other [1]. Such resonances are typically determined through experimental modal testing conducted in a lab environment under controlled and repeatable conditions. Global vehicle and suspension system response demonstrate soft nonlinear behavior, however. Their resonant frequencies may thus decrease under on-road input not reproducible in a lab environment. Subsequently, mode management charts derived from lab testing may not be representative of the vehicle's on-road dynamic response. This paper presents modal model determination methodologies, and examines suspension system and vehicle global dynamic response under lab modal test and operating conditions. Vehicle suspension modes measured under static and dynamic (rolling) conditions will be compared.

The durability of fuel tank straps is essential for vehicle safety. Extensive physical tests are conducted to verify designs for durability. Due to the complexity of the loads and the fuel-to-tank interaction, computer-aided-engineering (CAE) simulation has had limited application in this area. This paper presents a CAE method for fuel tank strap durability prediction. It discusses the analytical loads, modeling of fuel-to-tank interaction, dynamic analysis methods, and fatigue analysis methods. Analysis results are compared to physical test results. This method can be used in either a fuel-tank-system model or a full vehicle model. It can give directional design guidance for fuel tank strap durability in the early stages of product development to reduce vehicle development costs.

NASA's future missions to explore the solar system will be long-duration missions and could last years at a time. Human life support systems required for these missions must operate with very high reliability for long periods of time and must be highly regenerative, requiring minimum resupply. Such life support systems will make use of combining higher plants, microorganisms, and physicochemical processes to recycle air and water, process wastes, and produce food. Development of regenerative life support systems will be a pivotal capability for missions to the moon and Mars. One key step in the development process for these systems is the establishment of a human-rated test facility specifically tailored for evaluation of closed, regenerative life support systems--one in which long-duration testing can take place involving human test crews.

Wind Tunnel 8 of the Driveability Test Facility (DTF), which achieved full operational status in 2001, is designed to provide full powertrain, aerodynamic, and aero-acoustic test capabilities for automotive product development. In order for it to be fully integrated into product testing, the Ford product engineering community needed to correlate the facility. The major objective of the correlation is quantitative aerodynamic correlation, which will be achieved when aerodynamic coefficients measured in Wind Tunnel 8 can be understood in the context of aerodynamic measurements obtained in other wind tunnels that Ford has used for product testing. The motivation for this study is the aerodynamic interference that is present in all wind tunnels. Aerodynamic interference is the deviation between the true result—which is difficult to determine—and the actual result obtained from the wind tunnel.

Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center (JSC) serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat by up to eight persons. A variety of gas analyzers and dew point sensors are used to monitor the chamber atmosphere and the process flow upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space.

Current engine development processes typically involve extensive steady-state and simple transient testing in order to characterize the engine's fuel consumption, emissions, and performance based on several controllable inputs such as throttle, spark advance, and EGR. Steady-state and simple transient testing using idealistic load conditions alone, however, is no longer sufficient to meet powertrain development schedule requirements. Mapping and calibration of an engine under transient operation has become critically important. And, independent engine development utilizing accelerated techniques is becoming more attractive. In order to thoroughly calibrate new engines in accelerated fashion and under realistic transient conditions, more advanced testing is necessary.

Future NASA manned missions to the moon and Mars will require development of robust regenerative life support system technologies which offer high reliability and minimal resupply. To support the development of such systems, early ground-based test facilities will be required to demonstrate integrated, long-duration performance of candidate regenerative air revitalization, water recovery, and thermal management systems. The advanced life support Systems Integration Research Facility (SIRF) is one such test facility currently being developed at NASA's Johnson Space Center (JSC). The SIRF, when completed, will accommodate unmanned and subsequently manned integrated testing of advanced regenerative life support technologies at ambient and reduced atmospheric pressures.

Exhaust durability is an important measure of quality, which can be predicted using CAE with accurate mount loads. This paper proposes an innovative method to calculate these loads from measured mount accelerations. A Chrysler vehicle was instrumented with accelerometers at both ends of its four exhaust mounts. The vehicle was tested at various durability routes or events at DaimlerChrysler Proving Grounds. These measured accelerations were integrated to obtain their velocities and displacements. The differences in velocities and displacements at each mount were multiplied by its damping and stiffness rates to obtain the mount load. The calculation was conducted for all three translational directions and for all events. The calculated mount loads are shown within reasonable range. Along with CAE, it is suggested to explore this method for exhaust durability development.

In 1998, Rouhana et al. described development of a new device, called the IR-TRACC (InfraRed - Telescoping Rod for Assessment of Chest Compression). In its original concept, the IR-TRACC uses two infrared LEDs inside of a telescoping rod to measure deflection. One LED serves as a light transmitter and the other as a light receiver. The output from the receiver LED is converted to a linear function of chest compression using an analog circuit. Tests have been performed with IR-TRACC units at various labs around the world since 1998. A first-generation IR-TRACC system was retrofit into a Q3 dummy by TNO. Similarly, a mid sized male Hybrid III dummy thorax and a small female Hybrid III dummy thorax have been designed by First Technology Safety Systems (FTSS) such that each contains 4 second-generation IR-TRACC units. The second-generation IR-TRACC is the result of continued development by FTSS, especially in the areas of the analysis circuit, manufacturing and calibration methods.

Traditionally, vehicle emission testing has used non-intelligent analyzers to meet government-regulated standards. Typically, these instruments would provide a 0 to 5-volt signal to a central test cell computer which would then handle all calibrations including analyzer linearization, zero and span corrections, stability checks, time delays, and sample readings. Modern gas analyzers now contain intelligence within each individual analyzer; this has caused the calibration methods to change dramatically. New methods were developed in the bench control system to take advantage of the intelligence of the analyzers by creating a distributed control architecture. The zeroing, spanning, and linearization methods are quite different from the previous protocols. The results, however, will provide more accurate reading to be used in calculating vehicle emissions.

As SULEV emission regulations approach, the bag mini-diluter (BMD) technology is gaining acceptance as a replacement for the existing constant volume sampler (CVS) for SULEV exhaust emission measurement and certification. The heart of the BMD system is the direct vehicle exhaust (DVE) flow measurement system. Due to the transient nature of vehicle exhaust during a standard FTP emission test cycle, the DVE must be capable of rapid and accurate response in order to track these varying exhaust flow rates. The DVE must also be robust enough to accurately measure flow rate despite variations in exhaust gas composition, pulsation effects, and rapid changes in both exhaust temperature and pressure. One of the primary DVE systems used on BMDs is the E-Flow, an ultrasonic flow meter manufactured by Flow Technologies, Inc.

NASA's Advanced Life Support Program has included as part of its long-range planning the development of a large-scale advanced life support facility capable of supporting long-duration testing of integrated, regenerative biological and physicochemical life support systems. As the designated NASA Field Center responsible for integration and testing of advanced life support systems, Johnson Space Center has undertaken the development of such a facility--the Advanced Life Support Human-Rated Test Facility (HRTF). As conceived, the HRTF is an interconnected five-chamber facility with a sealed internal environment capable of supporting a test crew of four for periods exceeding one year. The life support system which sustains the crew consists of both biological and physicochemical components and will perform air revitalization, water recovery, food production, solid waste processing, thermal management, and integrated control and monitoring functions.

In this study, a full vehicle with durability tire model established with ADAMS is applied to simulate the dynamic behavior of the vehicle under severe rough road proving ground events, where the shock force-velocity characteristics are modeled as nonlinear curves and multi-stage representations, respectively. The shock forces and velocities at each corner are resolved and through full factorial DOE, the shock forces and velocities response surface models are established to analyze the sensitivities of shock force and velocity to the shock damping characteristics.

During an ExtraVehicular Activity (EVA), both the heat generated by the astronaut's metabolism and that produced by the Portable Life Support System (PLSS) must be rejected to space. The heat sources include the heat of adsorption of metabolic CO2, the heat of condensation of water, the heat removed from the body by the liquid cooling garment and the load from the electrical components. Although the sublimator hardware to reject this load weighs only 1.58 kg (3.48 lbm), an additional 3.6 kg (8 lbm) of water are loaded into the unit, most of which is sublimated and lost to space, thus becoming the single largest expendable during an eight-hour EVA. Using a radiator to reject heat from the astronaut during an EVA can reduce the amount of expendable water consumed in the sublimator. Last year we reported on the design and initial operational assessment tests of a novel radiator designated the Radiator And Freeze Tolerant heat eXchanger (RAFT-X).