Page 5 - Shock and Vibration Overview

Shock & Vibration Measurement

SHOCK & VIBRATION

MEASUREMENT

What, Why, Who, When, & Where?

Before we can get into sensor selection we need to answer some key questions:

1) What frequency range do you care about?
The frequency range will drive hardware; I’ve seen far too many engineers have the
wrong sensor and even the wrong DAQ (data acquisition) system for their application

that can lead to erroneous results.

2) What amplitude range is of interest?
Obviously you’ll need to select a sensor with a measurement range that includes the
amplitudes you or your customer care about; but it also heavily influences your DAQ

selection. Very small vibrations/accelerations like those in seismic applications will
require not only a very low noise and high sensitivity accelerometer; you’ll also need
a DAQ system with very low noise and ultra-high resolution. On the higher amplitude
end, it’s important to bear in mind what type of acceleration levels the DAQ
hardware will see. When measuring a wider range, resolution will also be important.

3) Who needs the data and why?
You’ll need to lean towards higher quality systems if your customer has a particular
test standard they need to have the system qualified to. The United States military
has a testing standard, MIL-STD-810 (vibration is section 514.6 and shock is 516.6) for
example; you won’t be able to qualify your system to meet such a standard with low
quality equipment. On the other hand, if you just need a rough handle of the shock

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