Processing COSMIC/FORMOSAT-3 Data for Slant Total Electron Content Measurements New leveling algorithm uses GPS multipath signals to provide an improved leveling of ionospheric measurements. NASA’s Jet Propulsion Laboratory, Pasadena, California The COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) mission has GPS (Global Positioning System) radio occultation dual-band receivers onboard. The received signals slice through the ionosphere, layer by layer, in much the same way as peeling off the layers of an onion. In order to use GPS signals for ionospheric measurements, they must be edited, phase leveled, and the hardware biases removed. The leveling algorithm used for ground-based GPS receivers is inadequate for space-based receivers due to substantially different multipath characteristics.

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Durability Analysis of a Vehicle by Virtual Test Model (VTM) For accurate prediction of fatigue failure in structural components, accurate prediction of dynamic force histories is required. Ashok Leyland Ltd., Chennai, India The criterion for structural failure must be based on failure modes of the component being designed. If the component is to withstand millions of cycles of load application, criterion for fatigue failure must be used. Fatigue damage caused by repeated dynamic loads depends on the number of cycles and the frequency of significant stresses. Therefore, for accurate prediction of fatigue failure in structural components, accurate prediction of dynamic force histories is required.

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Model-Based Prognostics for Batteries Accurate predictions can be made of the remaining useful life for individual discharge cycles, as well as for cycle life. Ames Research Center, Moffett Field, California The innovation provides enhanced health management routines for batteries. A mathematical model has been developed to describe battery behavior during individual discharge cycles, as well as over the cycle life. Different prognostic modes for estimating the state of charge, state of life, end of discharge, and/or end of life of a battery are provided. It employs a mathematical, rigorous reasoning framework for better understanding and representation, manipulation, and management of the various sources of uncertainty inherent in the prognostics of the remaining useful life in a battery. The models used to estimate the remaining useful life of batteries are linked to the internal electrochemical processes of the battery. The effects of load (and, by extension, temperature) have been incorporated into the models. The model is used in conjunction with a particle filtering framework to make state estimations and probabilistic predictions of remaining useful life for individual discharge cycles, as well as for battery life. The model fidelity improves when the influence of factors like temperature, discharge C-rate, end of discharge, state of charge after charging, etc., are explicitly incorporated. Model validation studies were conducted using data from a series of battery cycling experiments at various thermal and electrical loading conditions. In addition, the models and algorithms were integrated on an electric UAV and subsequently flown on numerous test flights. This Brief includes a Technical Support Package (TSP). Model-Based Prognostics for Batteries (reference ARC-16320-1) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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Application of a Physics-Based Stabilization Criterion to Flight System Thermal Testing Goddard Space Flight Center, Greenbelt, Maryland This innovation consists of a procedure and set of equations that allows thermal balance steady-state temperatures to be predicted hours before the balance is reached based on current temperature and rate-of-change measurements. This will allow tests to run faster, since thermal plateau settings may be adjusted prior to reaching an equilibrium state. Additionally, it will allow the test conductors to identify future limit violations hours before they may happen, which would increase flight hardware safety. A similar methodology can be used to predict component temperatures in flight, assuming a relatively constant sink temperature condition, which would be useful for long cool-down missions such as the James Webb Space Telescope (JWST). This Brief includes a Technical Support Package (TSP). Application of a Physics-Based Stabilization Criterion to Flight System Thermal Testing (reference GSC-16297-1) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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Cogging Torque Analysis of a Permanent Magnet Machine in a Wind Turbine Finite element analysis is used to analyze the effects of different designs on the reduction of cogging torque. Permanent magnet machines are used in many industrial applications because of their ability to produce high power densities. The market for such machines has been expanding due to the availability of affordable magnet materials, technological improvements, and advances in design and control. While still a relatively new phenomenon in wind turbines, permanent magnet generators are increasingly the focus of R&D in that field.

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Fast, High-Precision Readout Circuit for Detector Arrays The GEO-CAPE mission described in NASA’s Earth Science and Applications Decadal Survey requires high spatial, temporal, and spectral resolution measurements to monitor and characterize the rapidly changing chemistry of the troposphere over North and South Americas. High-frame-rate focal plane arrays (FPAs) with many pixels are needed to enable such measurements. This Brief includes a Technical Support Package (TSP). Fast, High-Precision Readout Circuit for Detector Arrays (reference NPO-47320) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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A System for Measuring the Sway of the Vehicle Assembly Building Tests have shown that the existing facility is safe. A system was developed to measure the sway of the Vehicle Assembly Building (VAB) at Kennedy Space Center. This system was installed in the VAB and gathered more than one total year of data. The building movement was correlated with measurements provided by three wind towers in order to determine the maximum deflection of the building during high-wind events. This Brief includes a Technical Support Package (TSP). A System for Measuring the Sway of the Vehicle Assembly Building (reference KSC-13773) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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ISS Ammonia Leak Detection Through X-Ray Fluorescence An astrophysics instrument can be used to detect and localize ISS ammonia leaks. Ammonia leaks are a significant concern for the International Space Station (ISS). The ISS has external transport lines that direct liquid ammonia to radiator panels where the ammonia is cooled and then brought back to thermal control units. These transport lines and radiator panels are subject to stress from micrometeorites and temperature variations, and have developed small leaks. The ISS can accommodate these leaks at their present rate, but if the rate increased by a factor of ten, it could potentially deplete the ammonia supply and impact the proper functioning of the ISS thermal control system, causing a serious safety risk. This Brief includes a Technical Support Package (TSP). ISS Ammonia Leak Detection Through X-Ray Fluorescence (reference GSC-16686-1) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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Hydrometeor Size Distribution Measurements by Imaging the Attenuation of a Laser Spot Measurement of the DSD’s second moment is made by way of the Beer-Lambert law. The optical extinction of a laser due to scattering of particles is a well-known phenomenon. In a laboratory environment, this physical principle is known as the Beer-Lambert law, and is often used to measure the concentration of scattering particles in a fluid or gas. This method has been experimentally shown to be a usable means to measure the dust density from a rocket plume interaction with the lunar surface. Using the same principles and experimental arrangement, this technique can be applied to hydrometeor size distributions, and for launch-pad operations, specifically as a passive hail detection and measurement system. This Brief includes a Technical Support Package (TSP). Hydrometeor Size Distribution Measurements by Imaging the Attenuation of a Laser Spot (reference KSC-13753) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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Victim Simulator for Victim Detection Radar This simulator can be placed for long periods of time in environments that would be unsafe for a human subject. Testing of victim detection radars has traditionally used human subjects who volunteer to be buried in, or climb into a space within, a rubble pile. This is not only uncomfortable, but can be hazardous or impractical when typical disaster scenarios are considered, including fire, mud, or liquid waste. Human subjects are also inconsistent from day to day (i.e., they do not have the same radar properties), so quantitative performance testing is difficult. Finally, testing a multiple-victim scenario is difficult and expensive because of the need for multiple human subjects who must all be coordinated. This Brief includes a Technical Support Package (TSP). Victim Simulator for Victim Detection Radar (reference NPO-48793) is currently available for download from the TSP library. Please Login at the top of the page to download.  

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