| タイトル | Probabilistic Analysis of Space Shuttle Body Flap Actuator Ball Bearings |
| 本文（外部サイト） | http://hdl.handle.net/2060/20070017862 |
| 著者（英） | Zaretsky, Erin V.; Jett, Timothy R.; Predmore, Roamer E.; Oswald, Fred B. |
| 著者所属（英） | NASA Glenn Research Center |
| 発行日 | 2007-01-01 |
| 言語 | eng |
| 内容記述 | A probabilistic analysis, using the 2-parameter Weibull-Johnson method, was performed on experimental life test data from space shuttle actuator bearings. Experiments were performed on a test rig under simulated conditions to determine the life and failure mechanism of the grease lubricated bearings that support the input shaft of the space shuttle body flap actuators. The failure mechanism was wear that can cause loss of bearing preload. These tests established life and reliability data for both shuttle flight and ground operation. Test data were used to estimate the failure rate and reliability as a function of the number of shuttle missions flown. The Weibull analysis of the test data for a 2-bearing shaft assembly in each body flap actuator established a reliability level of 99.6 percent for a life of 12 missions. A probabilistic system analysis for four shuttles, each of which has four actuators, predicts a single bearing failure in one actuator of one shuttle after 22 missions (a total of 88 missions for a 4-shuttle fleet). This prediction is comparable with actual shuttle flight history in which a single actuator bearing was found to have failed by wear at 20 missions. |
| NASA分類 | Systems Analysis and Operations Research |
| 権利 | Copyright, Distribution as joint owner in the copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/258551 |
