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iii.
Servo
In this smart car, one servo controls the direction of the car, and the other two, the
movement of the camera between X axis and Y axis, thus defining the coverage of
the camera. A servo is an automatic control system composed of DC motor,
reduction gear set, sensor, and control circuit. It defines the rotation angle of the
output shaft via delivering specific PWM signals. Generally, a servo supports a
maximum rotation angle of the shaft (like 180 degrees). It differs from a common
DC motor in the rotation mode: a DC motor rotates by circle when a servo rotates
in a certain degree and does not rotate in a round circle. Also, the former is used for
power supply by its whole-circle rotation, while the latter is applied to controlling
the rotation angle of an object (like joints of a robot).
