Electric servo drives refer to components of a machine that control its motor to provide the best possible performance. Servo drives ensure that the machine ramps up to the final speed as quickly as possible, operates at this speed for as long as possible, reduces speed as late as possible, and comes to a stop in good time. Servo drives are mainly used in mechanical, plant and system engineering and construction, in decentralized systems and in positioning systems (rotary, cross and multi-axis systems).
Electric servo drives receive commands (optional: control commands) from a process control system, a PLC or from a position controller (optional: motion control controller). They implement these, report the execution, completion and any malfunctions. If the load of the machine changes, electric servo drives can regulate the power autonomously and absorb the change.
Modern servo drives support various fieldbus systems, including Ethernet/IP, EtherCAT®, PROFINET, Modbus as well as CANopen and DeviceNet®. Older servo drives usually still have a serial interface.
At Festo, you will find electric servo drives as servo drive controllers or as stepper motor controllers.
The range of servo drives is specially designed for our toothed belt axes and ball screw axes as well as for our electric cylinders – perfectly combined with sizing software and enhanced with complete safety solutions in the mechanical and drive systems. Together with our automation platform and other integrated motion control solutions, the servo drives provide a virtually unlimited spectrum of solutions for industrial automation tasks, supported with innovative software solutions for engineering and configuration. Due to the variety of available fieldbuses such as Ethernet/IP, EtherCAT®, PROFINET, Modbus® as well as CANopen and DeviceNet®, the servo controllers are ideally suited to communicate directly with almost all programmable logic controllers (PLCs).
As a standard servo drive and in our core range you will find the electric, multi-protocol compatible servo drive CMMT-AS, which is one of the most compact servo drives on the market. It features precise force, speed and position control. Commissioning is simple and fast using software, where the desired fieldbus variant can also be set individually.
Our motor controller CMMP-AS, on the other hand, is particularly suitable for decentralized motion functions due to its numerous interfaces and functions. Its standardized interfaces allow easy integration into the mechatronic multi-axis modular system.
Our stepper motor controller program offers a simple and cost-effective way to implement electrical movements and makes moving and positioning easier than ever before – and much more cost-effective than conventional electrical solutions.
Very efficient for tasks with low power requirements is the electric multi-protocol capable servo drive CMMT-ST, which has proven itself especially in positioning tasks and point-to-point motion solutions. It is 50% more compact than our smallest servo drive CMMT-AS and is therefore ideally suited for use in simple applications.
To ensure cost-effective and high-performance production, machines must meet key operational criteria. A well-designed motion control system helps:
These are the areas where electric drive systems and servo technology excel. Basic tasks can be handled by asynchronous motors with frequency inverters. But when applications demand higher precision, speed, and dynamic movement, servo systems come into play.
A motion controller communicates via fieldbus with servo drives (or servo controllers), synchronizing every movement in the machine. It enables everything from simple point-to-point motion to highly coordinated, multi-axis profiles—ideal for CNC applications or robotics.
A servo drive system is a closed-loop control architecture designed to regulate position, speed, acceleration, and torque in a mechanical application. It typically consists of:
The term servo motor refers to any motor type—synchronous, BLDC, asynchronous, or stepper—operating within a closed-loop system that adjusts in real time based on sensor input. The servo drive applies pulse-width modulation (PWM) to modify voltage and frequency, delivering precise torque profiles in response to feedback.
This continuous control loop ensures high accuracy, maintaining exact position and velocity—even under variable loads or fast cycle times.
In contrast, stepper motors typically operate in open-loop systems without feedback. While more affordable, they lack the precision and adaptability of servo-based systems when operating under dynamic or high-load conditions.
Modern servo drives are designed for seamless integration with PLCs and motion controllers through industry-standard fieldbus protocols such as EtherCAT®, PROFINET, Ethernet/IP, CANopen, and others—enabling advanced motion synchronization and CNC applications.
Selecting the right servo drive requires considering various mechanical, electrical, and control factors. These include load dynamics, positioning requirements, and system integration needs.
To simplify the process, tools like the Electric Motion Sizing app from Festo provide valuable support. By entering key application parameters—such as mass, stroke length, and cycle time—you receive a tailored proposal for a matching electric drive solution.
This makes it easier to explore compatible motors, mechanical axes, and servo drives, helping ensure accurate sizing from the start.