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.