Micrometeoroid and Orbital Debris (MMOD) Shield Ballistic Limit Analysis Program
- Created: Sunday, 01 September 2013
This software implements penetration limit equations for common micrometeoroid and orbital debris (MMOD) shield configurations, windows, and thermal protection systems. Allowable MMOD risk is formulated in terms of the probability of penetration (PNP) of the spacecraft pressure hull.
For calculating the risk, spacecraft geometry models, mission profiles, debris environment models, and penetration limit equations for installed shielding configurations are required. Risk assessment software such as NASA’s BUMPER-II is used to calculate mission PNP; however, they are unsuitable for use in shield design and preliminary analysis studies.
The software defines a single equation for the design and performance evaluation of common MMOD shielding configurations, windows, and thermal protection systems, along with a description of their validity range and guidelines for their application. Recommendations are based on preliminary reviews of fundamental assumptions, and accuracy in predicting experimental impact test results.
The software is programmed in Visual Basic for Applications for installation as a simple add-in for Microsoft Excel. The user is directed to a graphical user interface (GUI) that requires user inputs and provides solutions directly in Microsoft Excel workbooks.
This work was done by Shannon Ryan of the USRA Lunar and Planetary Institute for Johnson Space Center. MSC-24582-1