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Accession Number N20130009067
Title Bayesian Approach for Reliability Assessment of Sunshield Deployment on JWST.
Publication Date 2013
Media Count 5p
Personal Author J. W. Evans L. D. Gallo M. P. Kaminskiy
Abstract Deployable subsystems are essential to mission success of most spacecraft. These subsystems enable critical functions including power, communications and thermal control. The loss of any of these functions will generally result in loss of the mission. These subsystems and their components often consist of unique designs and applications, for which various standardized data sources are not applicable for estimating reliability and for assessing risks. In this study, a Bayesian approach for reliability estimation of spacecraft deployment was developed for this purpose. This approach was then applied to the James Webb Space Telescope (JWST) Sunshield subsystem, a unique design intended for thermal control of the observatory's telescope and science instruments. In order to collect the prior information on deployable systems, detailed studies of 'heritage information' were conducted extending over 45 years of spacecraft launches. The NASA Goddard Space Flight Center (GSFC) Spacecraft Operational Anomaly and Reporting System (SOARS) data were then used to estimate the parameters of the conjugative beta prior distribution for anomaly and failure occurrence, as the most consistent set of available data and that could be matched to launch histories. This allows for an emperical Bayesian prediction for the risk of an anomaly occurrence of the complex Sunshield deployment, with credibility limits, using prior deployment data and test information.
Keywords Anomalies
Bayes theorem
Data processing
Heat shielding
James webb space telescope
Mathematical models
Probability density functions
Reliability analysis
Risk assessment

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54B - Astronomy & Celestial Mechanics
Corporate Author Goddard Space Flight Center, Greenbelt, MD.
Document Type Conference proceedings
Title Note N/A
NTIS Issue Number 1319
Contract Number N/A

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