A vibrator is a mechanical device to generate vibrations. The vibration is generated by an electric motor with an unbalanced mass on its driveshaft. Typically, they are components of larger products such as smartphones, pagers, vibrating toys, or video game controllers with a "rumble" feature. An eccentric rotating mass vibration motor (ERM) uses a small unbalanced mass on a DC motor when it rotates it creates a force that translates to vibrations. A linear resonant actuator (LRA) contains a small internal mass attached to a spring, which creates a force when driven.
