A servo motor controller is an electronic device that manages the operation of a servo motor. It receives input signals, typically from a microcontroller or a computer, and adjusts the motor's position, speed, and torque accordingly. This precise control makes servo motors ideal for applications requiring accurate movement, such as in robotics and automation. The controller works by sending a pulse-width modulation (PWM) signal to the servo motor, which interprets the signal to determine its desired position. By continuously adjusting the PWM signal, the controller ensures that the motor reaches and maintains the specified position, enhancing the performance of systems like CNC machines and robotic arms.