Technical Support Packages

Quantitative Analysis of Failure Mode in Adhesively Bonded Test Specimens

A fluorescence visualization technique is used. Langley Research Center, Hampton, Virginia After adhesively bonded mechanical test specimens have been tested to failure, the failure mode must be interpreted and quantified. Areas of the adherent that are bare (no residual adhesive remains) have undergone adhesive failure. The remainder of the surface has undergone cohesive failure. The ability to distinguish and accurately quantify the relative amounts of cohesive and adhesive failure on a failed bonding surface is of tremendous importance in the field of mechanical testing, and for the development of bonded assemblies. Some adhesives (and adherents) are fluorescent, meaning they re-emit light at a different wavelength after being irradiated by some lighting source. This property allows for quantitative analysis of the adhesive failure mode (adhesive and cohesive). A digital image of the fluorescing adhesive or adherent can be analyzed and quantified using publicly available software to determine the relative areas of exposed and covered adherent surface.

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Neutron Spectrometer for Inner Radiation Belt Studies

The instrument is inherently robust, cost-effective, compact, and modular. Goddard Space Flight Center, Greenbelt, Maryland The Earth’s magnetosphere offers a wealth of information on particle dynamics, acceleration, and trapping. Fast neutrons, produced in the Earth’s atmosphere by the impact of galactic cosmic rays (GCRs) and solar energetic particles (SEPs), are an important but poorly measured component of the radiation environment in the inner magnetosphere. Cosmic ray albedo neutron decay (CRAND), whereby atmospheric neutrons beta-decay into protons and electrons, is a significant source of energetic protons in the inner radiation belt. Current models of the inner proton belt rely heavily on Monte Carlo simulations for the CRAND component, validated primarily by a handful of single-point balloon measurements from the 1970s.

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Variable Acceleration Force Calibration System

Langley Research Center, Hampton, Virginia A variable acceleration calibration system combines an innovative mechanical system and a statistical design of experiments to calibrate multi-axis force transducers. This system can reduce calibration time, allow for improved calibration of large-scale transducers, provide mobility for on-site calibrations, allow multiple transducers to be calibrated simultaneously, and accommodate dynamic force calibration.

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A Synthetic Quadrature Phase Detector/ Demodulator for Fourier Transform Spectrometers

This method makes it possible to use simple, low-cost, high-resolution audio digitizers. Langley Research Center, Hampton, Virginia Fourier transform spectroscopy works by measuring a spectral/light signal through a Michelson interferometer. In order to know the wavelength of the signal, one must use a stable reference, which is typically a metrology laser. In a standard Fourier transform spectrometer (FTS) system, the laser signal also runs through the interferometer and the laser beam is guided to a separate detector that is then used to trigger an analog-to-digital converter, which then captures the spectral signal.

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Process to Fabricate Specific Sized Monodisperse Polystyrene Microparticles

Langley Research Center, Hampton, Virginia A new method was developed to prepare monodisperse nano to microparticles of polystyrene ranging from 0.5 to 2.5 microns in relatively large-quantity batches (2 L, 10% by weight in water). Current commercial sources are very expensive and can typically only be acquired on a relatively small scale. Monodisperse polystyrene in this size range is an important component of laser velocimetry measurements in wind tunnels, but has many other potential uses. Polystyrene microparticles have uses in paints/coatings, adhesives, bio/immunoassays, reaction catalysts, and chromatography materials. The main benefits of this technology are low cost, scalability, and selectable size.

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Diminutive Assembly for Nanosatellite deploYables (DANY) Miniature Release Mechanism

New deployment mechanism offers improved reliability with minimum space and weight penalty. Goddard Space Flight Center, Greenbelt, Maryland CubeSat appendices such as solar panels and antennas often need to be constrained by a release mechanism during launch. These appendices are then deployed once the desired orbit is reached. The usual constraint method used is a combination of an unpredictable/ unreliable fishing line and burning wire. If a proper release mechanism is used, it utilizes a considerable amount of CubeSat internal space, making the internal packaging of the satellite more difficult. These two methods have adverse effects on CubeSat performance.

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Quantitative Real-Time Flow Visualization Technique

This technique enables real-time monitoring of pressure fields and flow measurement. John H. Glenn Research Center, Cleveland, Ohio There is a need for experimental techniques that have low cost and rapid turnaround. It is also necessary to obtain quantitative information from such a method. Previous methods are either lacking in quantitative information such as dye or smoke injection, or require considerable set-up and cost such as PIV (particle image velocimetry). A method was developed for visualizing the pressure contours for a turbine cascade in real time to enable rapid evaluation of new concepts. A method for quantitative 3D flow visualization also was developed.

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