Which statement best describes servo motors in robotics?

• A. It has constant speed irrespective of load
• B. It cannot be used in robotics
• C. It is identical to a DC motor
• D. It provides precise position control

Answer: (D)

Servo motors in robotics are designed to provide precise position control through feedback and closed-loop control. They include a sensor that reports the actual shaft position and a controller that compares this to the commanded position, then adjusts the motor output to minimize error. This enables the joint to move to a specific angle and hold it even when external forces try to push it away, delivering repeatable, accurate positioning essential for robotic joints and manipulators.

This differs from a constant-speed motor, which would try to run at a set speed regardless of load and wouldn’t inherently reach or hold a particular position. A servo’s ability to regulate position comes from the feedback loop, not from simply spinning at a fixed speed.

A servo is not the same as a plain DC motor. A DC motor lacks the integrated feedback and control electronics that define a servo system, so it cannot guarantee precise positioning without additional sensing and control.