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The Waste and Hygiene Compartment will serve as the primary facility for metabolic waste management and personal hygiene on the United States segment of the International Space Station. The Compartment encloses the volume of two standard ISS racks and will be installed into Node 3 after launch inside a Multipurpose Logistics Module on the Space Shuttle. Long duration space flight requires a departure from the established hygiene and waste disposal practices employed on the Space Shuttle. This paper describes requirements and a conceptual design for the Waste and Hygiene Compartment that are both logistically practical and acceptable to the crew.

The Mars Scout Phoenix Lander successfully landed in the Martian northern latitude on May 25, 2008. The Robotic Arm, which was designed to dig and to transfer soil samples to other Lander instruments, contained a number of actuators that had specific operational windows on the Martian surface due to the bearing lubricant. The deployment of the Robotic Arm was planned for Sol 2 (Mars days are referred to “Sols”). A few weeks before Mars landing, the Robotic Arm operations team learned that a strict flight rule had been imposed. It specified that the deployment shall be accomplished when the actuators were at or above −25°C since the deployment activity was qualified with the actuators at −40°C. Furthermore, the deployment plan identified a window of opportunity between 13:00 Local Solar Time (LST, equivalent to dividing the Sol into 24 equal Martian hours) and 15:30 LST.

The Mars Science Laboratory will be the next Martian mobility system that is scheduled to launch in the fall of 2011. The ChemCam Instrument is a part of the MSL science payload suite. It is innovative for planetary exploration in using a technique referred to as laser breakdown spectroscopy to determine the chemical composition of samples from distances of up to about 9 meters away. ChemCam is led by a team at the Los Alamos National Laboratory and the Centre d'Etude Spatiale des Rayonnements in Toulouse, France. The portion of ChemCam that is located inside the Rover, the ChemCam Body Unit contains the imaging charged-coupled device (CCD) detectors. Late in the design cycle, the ChemCam team explored alternate thermal design architectures to provide CCD operational overlap with the Rover's remote sensing instruments. This operational synergy is necessary to enable planning for subsequent laser firings and geological context.

Phoenix, NASA's first Mars Scouts mission, will be launched in 2007 and will soft-land inside the Martian Arctic Circle, between north 65° and 72° North latitude, in 2008 to study the water history and to search for habitable zones. Similar to the IDD (Instrument Deployment Device) on the Mars Exploration Rovers (MER), Phoenix has a Robotic Arm (RA) which is equipped with a scoop to dig into the icy soil and to deliver the soil samples to instruments for scientific observations and measurements. As with MER, the actuators and the bearings of the Phoenix RA in a non-operating condition can survive the cold Martian night without any electrical power or any thermal insulation. The RA actuators have a minimum operating allowable flight temperature (AFT) limit of -55°C, so, warm-up heaters are required to bring the temperatures of all the RA actuators above the operating AFT limit prior to early morning operation.

This paper summarizes current work in the Environmental Science & Health Effects (ES&HE) Program being sponsored by DOE's Office of Heavy Vehicle Technologies (OHVT) through the National Renewable Energy Laboratory (NREL). The program is regulatory-driven, and focuses on ozone, airborne particles, visibility and regional haze, air toxics, and health effects of air pollutants. The goal of the ES&HE Program is to understand atmospheric impacts and potential health effects that may be caused by the use of petroleum-based and alternative transportation fuels. Each project in the program is designed to address policy-relevant objectives. Studies in the ES&HE Program have four areas of focus: improving technology for emissions measurements; vehicle emissions measurements, emission inventory development/improvement; and ambient impacts, including health effects.

Thermal characterization was performed on a vapor compression heat pump using a novel, hybrid two phase loop design. Previous work on this technology has demonstrated its ability to provide passive phase separation and flow control based on capillary action. This provides high quality vapor to the compressor without relying on gravity-based phase separation or other active devices. This paper describes the subsequent work done to characterize evaporator performance under various startup scenarios, tilt angles, and heat loads. The use of a thermal expansion valve as a method to regulate operation was investigated. The effect of past history of use on startup behavior was also studied. Testing under various tilt angles showed evaporator performance to be affected by both adverse and favorable tilts for the given compressor. And depending on the distribution of liquid in the system upon startup, markedly different performance can result for the same system settings and heat loads.

Annual fuel use for long-haul truck rest period idling is estimated at 667 million gallons in the United States. The U.S. Department of Energy's National Renewable Energy Laboratory's CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck climate control systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In order for candidate idle reduction technologies to be implemented at the original equipment manufacturer and fleet level, their effectiveness must be quantified. To address this need, a number of promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads.

As a result of the Viking missions in 1970s, the presence of a strong oxidant in Martian soil was suggested. Here we present a testable, by near-term missions, hypothesis that iron(VI) contributes to that oxidizing pool. Ferrate(VI) salts were studied for their spectral and oxidative properties and biological activities. Ferrate(VI) has distinctive spectroscopic features making it available for detection by remote sensing reflectance spectra and contact measurements via Mössbauer spectroscopy. The relevant miniaturized instrumentation has been developed or is underway, while XANES spectroscopy is shown to be a method of choice for the returned samples. Ferrate(VI) is capable of splitting water to yield oxygen, and oxidizing organic carbon to CO2. Organic oxidation was strongly abated after pre-heating ferrate, similar to the observations with Mars soil samples.

A key component of an Advanced Life Support (ALS) system is the solid waste handling system. One of the most important data sets for determining what solid waste handling technologies are needed is a solid waste model. A preliminary solid waste model based on a six-person crew was developed prior to the 2000 Solid Waste Processing and Resource Recovery (SWPRR) workshop. After the workshop, comments from the ALS community helped refine the model. Refinements included better estimates of both inedible plant biomass and packaging materials. Estimates for Extravehicular Mobility Unit (EMU) waste, water processor brine solution, as well as the water contents for various solid wastes were included in the model refinement efforts. The wastes were re-categorized and the dry wastes were separated from wet wastes. This paper details the revised model as of the end of 2001. The packaging materials, as well as the biomass wastes, vary significantly between different proposed Mars missions.

Spark-ignition engine fuel standards have been put in place to ensure acceptable hot and cold weather driveability (HWD and CWD). Vehicle manufacturers and fuel suppliers have developed systems that meet our driveability requirements so effectively that drivers overwhelmingly find that their vehicles reliably start up and operate smoothly and consistently throughout the year. For HWD, fuels that are too volatile perform more poorly than those that are less volatile. Vapor lock is the apparent cause of poor HWD, but there is conflicting evidence in the literature as to where in the fuel system it occurs. Most studies have found a correlation between degraded driveability and higher dry vapor pressure equivalent or lower TV/L = 20, and less consistently with a minimum T50. For CWD, fuels with inadequate volatility can cause difficulty in starting and rough operation during engine warmup.

This paper describes a method for predicting structural failure probabilities for automotive windshields. The predictive model is supported by the data from strength tests performed on specimens of automotive glass. Evaluations of stresses can be based on finite element calculations, or measurements of the residual stresses that arise from fabrication. Failure probabilities for each subregion of a windshield are estimated from the local state of stress, the surface area or length (for edge elements) of the subregion, and statistical distributions of glass strengths. Example calculations are presented that show the relative contributions of edge stresses, surface stresses and residual stresses to calculated failure probabilities.

In this paper, a three-dimensional (3D) microstructure-based finite element modeling method (i.e., extrinsic modeling method) is developed, which can be used in examining the effects of porosity on the ductility/fracture of Mg castings. For this purpose, AM60 Mg tensile samples were generated under high-pressure die-casting in a specially-designed mold. Before the tensile test, the samples were CT-scanned to obtain the pore distributions within the samples. 3D microstructure-based finite element models were then developed based on the obtained actual pore distributions of the gauge area. The input properties for the matrix material were determined by fitting the simulation result to the experimental result of a selected sample, and then used for all the other samples’ simulation. The results show that the ductility and fracture locations predicted from simulations agree well with the experimental results.

This paper describes results acquired from E-Tongue 2 and E-Tongue 3 which are arrays of planar three-element electrochemical cells and pH sensors. The approach uses ASV (Anodic Stripping Voltammery) to achieve a detection limit, which in the case of Pb, is below one μM which is needed for water quality measurements. The richness of the detectable species is illustrated with Fe where seven species are identified using the Pourbiax diagram. The detection of multiple species is illustrated using Pb and Cu. The apparatus was used to detect the electroactivity of the metabolic-surrogate, PMS (phenazine-methosulphate). Finally, four types of pH sensors were fabricated and characterized for linearity, sensitivity, and responsiveness.

The objective of this research is a detailed investigation of particulate sizing and number count from a spark-ignited, direct-injection (SIDI) engine at different operating conditions. The engine is a 549 [cc] single-cylinder, four-valve engine with a flat-top piston, fueled by Tier II EEE. A baseline engine operating condition, with a low number of particulates, was established and repeatability at this condition was ascertained. This baseline condition is specified as 2000 rpm, 320 kPa IMEP, 280 [°bTDC] end of injection (EOI), and 25 [°bTDC] ignition timing. The particle size distributions were recorded for particle sizes between 7 and 289 [nm]. The baseline particle size distribution was relatively flat, around 1E6 [dN/dlogDp], for particle diameters between 7 and 100 [nm], before dropping off to decreasing numbers at larger diameters. Distributions resulting from a matrix of different engine conditions were recorded.

A flight experiment to test the operation of an Electronic Nose developed and built at JPL and Caltech was done aboard STS-95 in October-November, 1998. This ENose uses conductometric sensors made of insulating polymer-carbon composite films; it has a volume of 1.7 liters, weighs 1.4 kg including the operating computer and operates on 1.5 W average power. In the flight experiment, the ENose was operated continuously for 6 days and recorded the sensors' response to changes in air in the mid-deck of the orbiter. The ENose had been trained to identify and quantify ten common contaminants at the 24-hour Spacecraft Maximum Allowable Concentration (SMAC) level. Most SMACs are on the order of 10-100 ppm. The experiment was controlled by collecting air samples daily and analyzing them using standard analytical techniques after the flight. The device is microgravity insensitive.

The Tropospheric Emission Spectrometer (TES), launched on NASA's Earth Observing System Aura spacecraft on July 15, 2004 has successfully completed over three years in space and has captured a number of important lessons. The instrument primary science objective is the investigation and quantification of global climate change. TES measures the three-dimensional distribution of ozone and its precursors in the lower atmosphere on a global scale. It is an infrared (IR) high resolution, imaging Fourier Transform Spectrometer (FTS) with a 3.3 to 15.4 μm spectral coverage required for space-based measurements to profile essentially all infrared-active molecules present in the Earth's lower atmosphere. The nominal on-orbit mission lifetime is 5 years. The Aura spacecraft flies in a sun-synchronous near-circular polar orbit with 1:38 pm ascending node.

Launched on NASA's Aura spacecraft on July 15, 2004, JPL's Tropospheric Emission Spectrometer (TES) has been operating successfully for over three years in space. TES is an infrared high resolution, imaging fourier transform spectrometer with spectral coverage of 3.3 to 15.4 μm to measure and profile essentially all infrared-active molecules present in the Earth's lower atmosphere. It measures the three-dimensional distribution of ozone and its precursors in the lower atmosphere on a global scale. The Aura spacecraft was successfully placed in a sun-synchronous near-circular polar orbit with a mean altitude of 705 km and 98.9 minute orbit period. The observatory is designed for a nominal 5 year mission lifetime. The instrument thermal design features include four temperature zones needed for efficient cryogenic staging to provide cooling at 65 K, 180 K, 230 K and 300 K.

A miniaturized electronic nose has been constructed at JPL in collaboration with Caltech. This array of conductometric sensors has been trained to detect and quantify the presence of vapors in the air; the compounds detected have been found as contaminants in shuttle air. This device has potential application as a miniature, distributed device for monitoring and controlling the constituents in air.

Simultaneous measurements were made for particle releases and off-gassing products produced by heating electrical wires. The wire samples in these experiments were heated to selected temperatures in a heating chamber and responses to vapor releases were recorded by the JPL Electronic Nose (ENose) and an Industrial Scientific ITX gas-monitor; particles released were detected by a TSI P-Trak particle counter. The temperature range considered for the experiment is room temperature (24−26°C) to 500 °C. The results were analyzed by overlapping responses from the ENose, ITX gas sensors and P-Trak, to understand the events (particle release/off-gassing) and sequence of events as a function of temperature and to determine qualitatively whether ENose may be used to detect pre-combustion event markers.

We have elicited a reliable Raman spectral signature for glucose in rabbit aqueous humor across mammalian physiological ranges in a rabbit model stressed by recent myocardial infarction. The technique employs near infrared Raman laser excitation at 785 nm, multivariate analysis, non-linear artificial neural networks and an offset spectra subtraction strategy. Aqueous humor glucose levels ranged from 37 to 323 mg/dL. Data were obtained in 80 uL samples to anticipate the volume constraints imposed by the human and rabbit anterior chamber of the eye. Total sample collection time was 10 seconds with total power delivered to sample of 30 Mw. Spectra generated from the aqueous humor were compared qualitatively to artificial aqueous samples and an excitation offset technique was devised to counteract broadband background noise partially obscuring the glucose signature.