Drive modules for servomotors are a standard industrial component. Small industrial servomotors are typically electronically commutated brushless motors. Technologies used include pneumatic activators, hydraulic cylinders, and electronic servomotors. The first servomotors were developed with synchros as their encoders. Brushless DC motors are widely used as servomotors for machine tool servo drives. Hysteresis motors are manufactured in sub-fractional horsepower ratings, primarily as servomotors and timing motors. Simple servomotors may use resistive potentiometers as their position encoder. Modern servomotors use rotary encoders, either absolute or incremental. Instead of servomotors, sometimes a motor with a separate, external linear encoder is used. The pilot's controls were connected to hydraulic servomotors then connected through springs to the gyro. Electric servomotors are the actuators for mechanical systems ranging from robotic systems to modern aircraft. Servomotors are used for mechanical displacement, positioning or precision motion control. Servomotors are used for both high-end and low-end applications. Servomotors are generally used as a high-performance alternative to the stepper motor. Servomotors are used in applications such as robotics, CNC machinery or automated manufacturing.