Page 48 - Shock and Vibration Overview
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Response Spectrums
Figure 30: The vibration response spectrum of the simplified PSD is shown along with the relative
displacement.
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Tom Irvine’s 16 webinar goes through the vibration response spectrum in much more
detail and is a great reference if interested in the vibration response spectrum. More
detail is available on his VRS tutorial.
Shock Response Spectrum
Similar to the vibration response spectrum, a shock response spectrum is used to
calculate the response for a given shock excitation. The math and use case is very similar
in both instances; it enables the engineer to design his/her system avoiding certain
natural frequencies that would amplify the shock input.
Let’s look at an academic example of designing a system to survive a 1g, 1 second half
sine pulse. We’ll explore the response from seven different resonant frequencies (and
corresponding spring stiffness) ranging from 0.063 Hz to 4.0 Hz. The system is shown in
Figure 31, this information is all taken from the vibrationdata SRS educational animation
page.
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