Measurements of Acceleration on Delta GEM Boosters and Road Tests of GPS Position Sensing
Abstract
The results of an effort to localize the position of impact on a Delta graphite epoxy motor (GEM) case using accelerometers are reported. Acceleration from impacts produced by a hammer on an empty case was easily sensed using 50-g accelerometers. When the motor case is filled with inert propellant, the magnitude of the acceleration is reduced and damped out rapidly, making detection at longer distances over 2 m more difficult unless more sensitive accelerometers are used. A method to localize or triangulate an impact location was developed and tested using acceleration data. It was necessary to filter the data to reduce its bandwidth to reduce dispersion effects that affect the velocities of the disturbances being sensed. The disturbances were shown to originate from structural deformations. Results from road tests to sense the locations of a GEM motor using GPS are reported. The motor was driven over select roads at Edwards AFB. This effort was part of a larger effort to monitor the health of GEM motor cases at Edwards. Further details of tests at Edwards AFB are described in "Health monitoring for Graphite/Expoxy Motor Cases," ed. by R. Welle, Aerospace Technical Report, TR-2000(1222)-1.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 25, 2000
- Accession Number
- ADA381456
Entities
People
- D. J. Chang
- E. M. Yohnsee
- E. W. Fournier
- S. T. Amimoto
Organizations
- The Aerospace Corporation