The electric form of these devices produces linear or rotary force, thus making them a type of actuator. For ten points each:
[10e] Name these devices that convert electrical energy to mechanical energy. DC forms of these devices can be brushed or brushless.
ANSWER: electric motors [accept DC motors]
[10m] A DC motor, a position potentiometer, and a specialized microcontroller form a common type of these devices, which are defined as precise motor-driven components with a positive feedback mechanism.
ANSWER: servomotors
[10h] Controlling hobby servos typically uses this technique, which converts any analog signal into a rectangular wave with a variable duty cycle.
ANSWER: pulse-width modulation [or PWM; accept pulse-duration modulation or PDM; accept pulse-length modulation or PLM]
<Ezra Santos, Other Science>