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Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.

This paper presents some of the challenges and successful outcomes in developing the aerodynamic characteristics of the Chevrolet Volt, an electric vehicle with an extended-range capability. While the Volt's propulsion system doesn't directly affect its shape efficiency, it does make aerodynamics much more important than in traditional vehicles. Aerodynamic performance is the second largest contributor to electric range, behind vehicle mass. Therefore, it was critical to reduce aerodynamic drag as much as possible while maintaining the key styling cues from the original concept car. This presented a number of challenges during the development, such as evaluating drag due to underbody features, balancing aerodynamics with wind noise and cooling flow, and interfacing with other engineering requirements. These issues were resolved by spending hundreds of hours in the wind tunnel and running numerous Computational Fluid Dynamics (CFD) analyses.

Understanding the flow characteristics and, especially, how the aerodynamic forces are influenced by the changes in the vehicle body shape, are very important in order to improve vehicle aerodynamics. One specific goal of aerodynamic shape optimization is to predict the local shape sensitivities for aerodynamic forces. The availability of a reliable and efficient sensitivity analysis method will help to reduce the number of design iterations and the aerodynamic development costs. Among various shape optimization methods, the Adjoint Method has received much attention as an efficient sensitivity analysis method for aerodynamic shape optimization because it allows the computation of sensitivity information for a large number of shape parameters simultaneously.

NASA's Deep Space Network (DSN) uses high-power transmitters on its large antennas to communicate with spacecraft of NASA and its partner agencies. The prime reflectors of the DSN antennas are parabolic, at 34m and 70m in diameter. The DSN transmitters radiate Continuous Wave (CW) signals at 20 kW - 500 kW at X-band and S-band frequencies. The combination of antenna reflector size and high frequency results in a very narrow beam with extensive oscillating near-field pattern. Another unique feature of the DSN antennas is that they (and the radiated beam) move mostly at very slow sidereal rate, essentially identical in magnitude and at the opposite direction of Earth rotation.

To cope with the increasing number of advanced features (e.g., smart-phone integration and side-blind zone alert.) being deployed in vehicles, automotive manufacturers are designing flexible hardware architectures which can accommodate increasing feature content with as fewer as possible hardware changes so as to keep future costs down. In this paper, we propose a formal and quantitative definition of flexibility, a related methodology and a tool flow aimed at maximizing the flexibility of an automotive hardware architecture with respect to the features that are of greater importance to the designer. We define flexibility as the ability of an architecture to accommodate future changes in features with no changes in hardware (no addition/replacement of processors, buses, or memories). We utilize an optimization framework based on mixed integer linear programming (MILP) which computes the flexibility of the architecture while guaranteeing performance and safety requirements.

The study aims at analyzing the tool utilization by using a real-time machining simulation and investigating the behavior of the parameters which affect the tool wear based on the results of the analysis. In this study, the method of calculation of parameters which are necessary to predict the tool wear by using Z-map based machining simulation is developed. Furthermore, the possibility of estimating the tool wear from the results of the simulation was also examined by performing the real cutting experiments.

The Cassini spacecraft, NASA's mission to investigate the Saturn system, has undergone a system-level thermal balance test program to permit verification of the engineering subsystem thermal designs in the simulated worst-case environments. Additionally, other objectives such as functional checkouts, collection of thermal data for analytical model adjustment, vacuum drying of propellant tanks, and flight temperature transducer verification were also completed. In the interest of cost and schedule, transient off-Sunpoint conditions were not tested. The testing demonstrated that the required system resources such as heater power and radiator area were adequate for all engineering subsystems. The only changes required from the results were related to the operation of some of the subsystems. In the instance of the thruster cluster assemblies, allowable flight temperature limits were exceeded for the assumed operational environment.

The current status of III-V semiconductor diode lasers emitting between 1 -5 μm wavelengths to be used as light sources for absorption spectroscopy is reviewed. The emission wavelength of the laser is chosen to coincide with the primary absorption line of a molecule or one of its many overtones. The lasers, with a single longitudinal mode emission, are wavelength tuned over several angstroms by modulating the drive current of the device. This sweeping of the wavelength leads to the nomenclature tunable diode laser or TDL. Single mode distributed feedback (DFB) strained layer InGaAs(P) lasers grown on InP substrates with emission wavelengths from 1.2 to 2.06 μm have been developed at JPL, and several devices will be used for planetary atmospheric studies for the first time.

The exploration of Mars is a major thrust of NASA. Some of the important goals of this exploration are the search for life; understanding the planet's evolution by in-situ and remote scientific measurements; developing an inventory of useful resources, including accessible water; and sample return as a precursor to human exploration. One of the key challenges of Mars's exploration hard-ware--- rovers, landers, probes, and science instruments -- is to be able to survive the planet's harsh environment on and below surface. This paper discusses the thermal challenges posed by relatively large temperature variations, analyses and experimental work done at JPL to address these challenges.

This paper entails the design and development of a NASA testing system used to simulate wheel operation in a lunar environment under different loading conditions. The test system was developed to test the design of advanced nonpneumatic wheels to be used on the NASA All-Terrain Hex-Legged Extra-Terrestrial Explorer (ATHLETE). The ATHLETE, allowing for easy maneuverability around the lunar surface, provides the capability for many research and exploration opportunities on the lunar surface that were not previously possible. Each leg, having six degrees of freedom, allows the ATHLETE to accomplish many tasks not available on other extra-terrestrial exploration platforms. The robotic vehicle is expected to last longer than previous lunar rovers.

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization.

In recent years, several different technologies have been considered for use in environmental monitoring and control of spacecraft habitat. These technologies have included monitoring for both water and air. This paper will discuss construction of a trade space for environmental monitoring technologies. Previous trade space metric approaches are reviewed and a new approach is outlined. Trade space considerations include the usual mass, power and volume, along with sensitivity, accuracy, speed of response, frequency of measurement and ease of use. These considerations will be discussed in the context of Constellation program vehicles. In addition to a new approach for trade space construction, this paper will briefly discuss the application of this trade space to a selection of technologies taken from NASA programs, ESA programs, COTS technologies and DoD programs.

There is a need to develop improved film capacitors for high temperature, high energy density and high reliability applications. The work reported here has resulted in self-healing capacitor technology applicable to a wide variety of polymer film substrates that prevents catastrophic failures and provides safe, reliable operation in power electronic circuits. This paper describes the performance of 500-2000 Volt metalized film capacitors operating at up to 160°C under a variety of duty conditions. Data on equivalent series resistance (ESR) and power dissipation (DF), peak and Root Means Square (RMS) current ratings, and other critical performance parameters are presented. The features and benefits of both dry wrap-and-fill and liquid-impregnated hermetically sealed constructions are discussed. This work was sponsored by the US Army Research Laboratory.

One startling realization that's come from NASA's explorations of the satellites of Jupiter and Saturn is that the so-called “habitable zone” around our Sun may not be restricted to Earth's vicinity. The Galileo mission found conditions that might support life on two Jovian moons-Europa & Callisto. This raises the possibility of habitable zones elsewhere near the outer planets. Consideration of human missions beyond Mars, likely to occur sometime beyond the year 2040, exceeds the horizon of even the most advanced planning activities within NASA. During the next 25 to 30 years, robotic spacecraft are envisioned to explore several moons of outer planets, especially Europa and Titan. Since Callisto lies well outside Jupiter's radiation belt, and there is evidence of water ice there is a compelling rationale to send human explorers to that Jovian moon.

The first concept and early experiments of a mechanical counter pressure (MCP) spacesuit were published by Webb in the late 1960's. MCP provides an alternative approach to the conventional full pressure suit that bears some significant advantages, such as increased mobility, dexterity, and tactility. The presented ongoing research provides a thorough investigation of the physiological effect of mechanical counter pressure applied onto the human skin. In this study, we investigated local microcirculatory effects produced with negative and positive ambient pressure on the lower body as a preliminary study for a lower body garment. The data indicates that the positive pressure was less tolerable than negative pressure. Lower body negative and positive pressure cause various responses in skin blood flow due to not only blood shifts but also direct exposure to pressure differentials.

The first concept and early experiments of a Mechanical Counter Pressure (MCP) spacesuit were published by Webb in the late 1960’s. MCP provides an alternative approach to the conventional full pressure suit that bears some potential advantages, such as increased mobility, dexterity, and tactility. The presented ongoing research provides a thorough investigation of the physiological effect of mechanical counter pressure applied onto the human skin. Preliminary results are presented from glovebox testing with an existing MCP glove. The data indicates that properly applied mechanical counter pressure greatly reduces the effect of low-pressure exposure, which makes MCP a viable technology for spacesuit gloves.

This paper outlines a process to assess the aerodynamic performance of different vehicle exterior surfaces. The initial section of the paper summarizes the details of white-light scanning process that maps entire vehicle to points in Cartesian co-ordinate system which is followed by the conversion of scanned points to theme surface. The concept of point-cloud modeling is employed to generate a smooth theme surface from scanned points. Theme surfaces thus developed are stitched to under-body/under-hood (UB/UH) parts of the base vehicle and the numerical simulations were carried out to understand the aerodynamic efficiency of the surfaces generated. Specifics of surface/volume mesh generated, boundary conditions imposed and numerical scheme employed are discussed in detail. Flow field over vehicle exterior is thoroughly analyzed. A comparison study highlighting the effect of front grilles in unblocked condition along with air-dam on flow field has been provided.

This paper presents development work on the design and analysis of the windshield wiper system. Three design categories are presented: geometrical design, wiper module and motor kinetics, and snow block structural analysis method. A comprehensive structural analysis method is outlined to determine the wiper system capability for continuous operation under a snow blocked condition. By using this design and analysis method, a robust windshield wiper system will be achieved.

Engineering has continuously strived to improve the vehicle development process to achieve high quality designs and quick to launch products. The design process has to have the tools and capabilities to help ensure both quick to the market product and a flawless launch. To achieve high fidelity and robust design, mistakes and other quality issues must be addressed early in the engineering process. One way to detect problems early is to use the math based modeling and simulation techniques of the analysis group. The correlation of the actual vehicle performance to the predictive model is crucial to obtain. Without high correlation, the change management process begins to get complicated and costs start to increase exponentially. It is critical to reduce and eliminate the risk in a design up front before tooling begins to kick off. The push to help achieve a high rate of correlation has been initiated by engineering management, seeing this as an asset to the business.

Current manufacture of alternative energy sources for automobiles, such as fuel cells and lithium-ion batteries, uses repeating energy modules to achieve targeted balances of power and weight for varying types of vehicles. Specifically for lithium-ion batteries, tens to hundreds of identical plastic parts are assembled in a repeating fashion; this assembly of parts requires complex dimensional planning and high degrees of quality control. This paper will address the aspects of dimensional quality for repeated, injection molded thermoplastic battery components and will include the following: First, dimensional variation associated with thermoplastic components is considered. Sources of variation include the injection molding process, tooling or mold, lot-to-lot material differences, and varying types of environmental exposure. Second, mold tuning and cavity matching between molds for multi-cavity production will be analyzed.