Page 45 - Shock and Vibration Overview
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Response Spectrums
Figure 26: The raw data and a corresponding power spectral density are shown for 10,000 data
points recorded with a Slam Stick on the base of a commercial airplane seat.
Using the MATLAB GUI package on Tom Irvine’s vibrationdata blog the transmissibility
ratio for a 250 Hz single-degree-of-freedom system can be calculated, shown in Figure
27. This assumes the system has a quality factor (Q) of 10. The response of such a
system would amplify the vibration amplitude by 100 times! The overall RMS vibration
level of a 250 Hz is nearly 0.8g RMS compared to the 0.1g RMS level of the base
vibration. That’s a significant increase in the vibrational environment that the screen
would have to survive.
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