Voice coil actuator
Magnetic circuits

Linear motors or actuators with moving coils are frequently used in applications requiring high motion dynamics with low amplitude. Figure 11 illustrates the E-shaped structure. It is made of a ferromagnetic material with little or no saturation, and supports two permanent magnets with high energy density. The moving coil is thus placed in an air gap with constant induction. The result is a force that is proportional to the current and whose direction is linked to its sign.

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