1. Vibrations

1.1 Definition

A vibration is an oscillating movement around an equilibrium position. This motion can be very simple, as in the case of a sinusoidal vibration, or more complex, as in the case of random vibrations.

A vibration is characterized by information on its amplitude and frequency, i.e. the number of oscillation occurrences per second.

For mechanical vibrations applied to electronic boards, vibration amplitude is frequently expressed in g units, the acceleration due to the Earth's gravity g, or in m.s- ² (1 g = 9.81 m.s- ² ), while frequency is expressed in hertz (Hz) or s- ¹ .