Mechanical Vibrations: Theory and Practice

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Fundamentals of Vibration Analysis

1.1 INTRODUCTION

Any motion that repeats itself after an interval of time is called vibration or oscillation. The common day-to-day examples of vibrations are swinging pendulum of the clock and motion of plucked string of a musical instrument. The theory of vibrations deals with the study of oscillatory motions of bodies/components of body and the forces associated with them. The vibrations experienced by the components/structures usually result in their stretching/unstretching or twisting/untwisting or both. As a result, they experience alternating stresses and thereby stress-induced fatigue. Depending on the magnitude and the number of cycles of alternating stresses, the component may fail earlier or later. ...