Servo Motors

About servo motors

Servo motors are rotary or linear actuators that provide precise control of angular or linear position, velocity, and acceleration. They consist of a motor, a feedback device (typically an encoder or resolver), and often an integrated drive or a separate servo drive. Two primary types are AC servo motors, generally three-phase synchronous motors, and DC servo motors, which can be brushed or brushless. Integrated servo motors combine the motor, drive, and feedback into a single unit, simplifying wiring and reducing footprint. Key selection parameters include continuous torque (typically in Nm or oz-in), peak torque, continuous power (W or kW), rated speed (RPM), and voltage (VDC or VAC). Feedback resolution (counts per revolution) and accuracy are critical for precision applications. Form factors vary from NEMA frame sizes (e.g., NEMA 17, 23, 34) to flange-mounted designs, with various shaft configurations including keyed, smooth, and hollow. Environmental ratings like IP codes (e.g., IP65 for dust and water resistance) are important for industrial environments. Common materials for motor housings include aluminum and steel, with various surface treatments for corrosion resistance. Drive interfaces typically include EtherCAT, PROFINET, SERCOS, and CANopen, facilitating integration into industrial control systems.