UTC Aerospace Systems

About: UTC Aerospace Systems is a based out in . It is known for research contribution in the topics: China & Medicine. The organization has 248 authors who have published 416 publications receiving 3733 citations. The organization is also known as: UTAS.

Spacecraft Charging Related Risk of Floating Connector Pins

Abstract: Every national spacecraft charging related design guideline or design standard includes prohibitions against floating, or ungrounded, connector pins. The rationale is obvious. A floating connector pin represents ungrounded metal with a propensity to accumulate charge from the space plasma environment and, upon breakdown, effectively couple the discharge energy directly into sensitive system electronics by virtue of adjacent pins and cables. Satellite designers may recognize that, seemingly as common as the rationale is obvious, there are instances in violation of this clear guideline and impassioned arguments for permissions to do so. This paper represents a comprehensive effort to quantitatively, theoretically, analytically, and empirically assess the risk associated with ungrounded connector pins in the selected (geostationary earth orbit and medium earth orbit) orbits.

Measurements and modeling of LWIR spectral emissivity of contaminated quartz sand

Abstract: The fundamental understanding of effects of liquid contaminants on the longwave infrared spectral emissivity of surfaces contaminated is desirable. This research describes modeling and longwave infrared spectral emissivity measurements for samples of SiO 2 (sand) with and without 0.3% (by weight) of SF96 (poly dimethyl siloxane) oil. Two different sand particle size ranges were considered. The modeling was performed using a microscattering code and the empirical emissivity measurements were made outdoors using a D&P Instruments Model 102F MicroFTIR non-imaging spectrometer. The data were calibrated and processed to retrieve the spectral emissivity. General observations included a significant increase in emissivity in the 8 to 9 and 12.5 to 13 micron regions due to the presence of the SF96. The comparison between the modeled and measured emissivities shows a consistent trend and significant separability between the spectral emissivity of sand with and without the SF96 present.