From: Jet Propulsion Laboratory
Posted: Tuesday, January 22, 2002
Last week - a major milestone was reached, environmental testing began on the spacecraft!! On Monday, January 14th, the spacecraft was put in final configuration in the cleanroom, and then moved to the vibration facility at APL. Our picture of the week shows the spacecraft mounted on the upper vibration table for the z-axis (thrust) test. The test sequence consists of a long day of extensive functional testing of all the spacecraft systems, followed the next day by the actual vibration test. The day of the vibration test is also quite long. Accelerometers have been placed throughout the spacecraft in specific locations determined by our lead structural engineer. The vibration test starts with a low level survey to check out the operation of all the accelerometers, and to get a first cut measure of any resonance. This data is analyzed, and the next step is to do a quarter level vibration. The process is repeated for half level and then finally a full level vibration. So, while the actual vibration test takes about a minute, the set-ups, analysis and checks require about a day to complete. Following the day of vibration testing is a day of conducting the same functional tests as those run just prior to the vibration test. This is to determine if the exposure to the vibration damaged/impacted any system on board. This pattern was repeated during the week - Tuesday and Thursday were functional testing, the z-axis was tested Wednesday, and the y-axis was tested Friday. So far, the testing is going very well....
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