An actuator coil is a conductor wound into a coil that produces a magnetic field when electric current flows through it. The magnetic force can move a mechanism or switch a component, such as the moving elements in an electromechanical display.
In cyber security, actuator coils are relevant as parts of physical devices that may be controlled by embedded systems or networked equipment. Attacks on those systems can misuse control signals to trigger unwanted movement or switching, while defenses include restricting access to control interfaces and monitoring for abnormal commands. In manufacturing, consistent winding helps ensure predictable actuator behavior.