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Chang, Kurng

Publications and source records attributed to Chang, Kurng.

Force limited vibration testing of Cassini spacecraft cosmic dust analyser

The testing of the cosmic dust analyzer for the Cassini mission using the force limited method in order to avoid overtesting and to verify the ability of the specimen design to withstand the loads during launch and cruise, is reported on. In order to implement the method, force gages, fixtures and a test controller are required and the test specimen is subjected to sine vibration, random vibration and half sine shock. The practical aspects of the use of the force limited method are described. Due to the high loads and the weak design of the structural element, a notching method is used which provides the possibility of limiting the excitation to flight expected levels.

Jahn, Heiko

Three-dimensional test requirement for random vibration testing

An approach to defining and evaluating three-dimensional vibration test requirements is discussed. The approach is used to develop the three-dimensional space random-vibration test requirements for missile components subjected to truck transportation environments. One-dimensional testing parameters such as power spectral density and overall g rms values for three mutually perpendicular directions represent the test requirements. The coherence characteristics between each input axis were established and adjusted empirically in an attempt to simulate the cross-correlation in three-dimensional random vibration excitation.

Chang, Kurng