Page 4 - Shock and Vibration Overview

Vibration Introduction

VIBRATION INTRODUCTION

All bodies possessing mass and elasticity are capable of vibration; which basically means
everything you see and touch can vibrate and are impacted from shock events. As the
world around us gets increasingly more automated with more and more powerful
machinery, vibration and its destructive strength is on the forefront of any mechanical
engineer’s mind during the design and testing process.

I’m sure everyone knows what vibration is; the device in your pocket probably reminds
you far too frequently throughout the day! But here’s the technical definition: vibration
is an oscillating motion about a point of equilibrium. Mechanical shock is a sudden

change of acceleration that generally excites a structure’s resonance. A shock event is
basically a type of vibration where the excitation is non-periodic; much of the test setup
and analysis between shock testing is similar to vibration testing. Plus, the tendency for
shock events to induce a vibratory response in the structure makes it worthwhile to
discuss the shock and vibration testing together. Mechanical shocks and vibrations have
become very pervasive in our ever day lives, so measuring and measuring and
understanding their impact on your system is an important part of mechanical design.

Shock and vibration measurement can be defined as “the art and science of measuring
and understanding a structure’s response to a dynamic environment.” Shock and
vibration testing goes beyond simply data acquisition, it is only effective when you are
able to understand what the data means for your application. And it takes some creative

skill to properly gather and analyze your shock and vibration data.

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