The International Space Station Comparative Maintenance Analysis(CMAM)
Abstract
The following thesis describes the current model (the Reliability and Maintainability Assessment Tool RMAT) used by NASA and related prime contractors for the forecasting of Orbital Replacement Unit (ORU) failure rates and associated maintenance demands for the International Space Station (ISS). A new model (the Comparative Maintenance Analysis Tool CMAM) is introduced and developed for replicating some of the basic functionality of RMAT in order to provide a comparative look at RMAT results. The CMAM program, developed in Visual Basic.net and dynamically linked to a Microsoft ACCESS database, focuses on a representative set of critical Orbital Replacement Units (ORUs that represent key items that require both internal and external maintenance in both pressurized and un- pressurized storage) and generated failure rate data for each critical ORU. The results of the CMAM model are then compared with the failure rates generated by RMAT program for the same set of critical ORUs. These two independently developed sets of data are then analyzed against historic failure rates for these ISS parts. The results of this analysis are used to conduct a sensitivity analysis of both the CMAM and RMAT programs in order to help identify the primary contributing factors behind divergence issues between forecasted / predicted failures and associated maintenance from actual (historical) failure rates. Recommendations are provided, based upon the results of the comparison, with respect to the sensitivity of RMAT to changes in certain input parameters, as well as on the feasibility of implementing CMAM as a comparative tool for use by both NASA and Boeing L&M personnel for the purpose of RMAT sensitivity analysis, as well as use in initial operational planning for optimizing ORU stocking levels while awaiting more comprehensive RMAT results.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2004
- Accession Number
- ADA427287
Entities
People
- Brian T. Soldon
Organizations
- Naval Postgraduate School