Servo motor is an electrical device which can be used to rotate objects (like robotic arm) precisely. It is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity and acceleration.
Servo implies an error sensing feedback control which is utilized to correct the performance of a system.
It is actually an assembly of four things: a normal DC motor, a gear reduction unit, a position-sensing device and a control circuit. The DC motor is connected with a gear mechanism which provides feedback to a position sensor which is mostly a potentiometer. From the gear box, the output of the motor is delivered via servo spline to the servo arm. For standard servo motors, the gear is normally made up of plastic whereas for high power servos, the gear is made up of metal.
Servo motor has rotation angle that varies from 0° to 180°
Servo Motor Pinout
|+VCC (Red)||Connect +VCC supply to this pin. For 9g Micro Servo it is 4.8 V (~5V).|
|Ground (Brown)||Connect Ground to this pin.|
|Control Signal (Orange)||Connect PWM of 20ms (50 Hz) period to this pin.|