Robots, as a crucial pillar of an intelligent society, have been widely integrated into various fields such as industrial manufacturing, medical services, and smart homes, performing complex and diverse tasks. In the wave of intelligent transformation, the continuous iteration and upgrading of robot technology is particularly critical. The industrial sector, in particular, has placed increasingly stringent technical requirements on the motion accuracy, operational efficiency, and stability of robots. As the core of a robot system, the performance improvement of the servo control system is essential, becoming a breakthrough point for driving the leapfrog development of robots.

  I. Servo Systems in Industrial Robots 

  1. Composition and Function of Servo Systems

  A servo system (also known as a follow-up system) is a feedback control system used to accurately follow or reproduce a process. A servo system is an automatic control system that enables the output controlled variables, such as the position, orientation, and state of an object, to follow any changes in the input target (or given value). 

  A robot servo system consists of four parts: servo motors, transmission devices, encoders, and controllers. It controls the robot's motion through a closed-loop operation, and its performance affects the robot's positioning accuracy, motion trajectory, and stability.

  Servo systems are products developed based on frequency conversion technology; they are automatic control systems that use mechanical position or angle as the controlled object. Besides speed and torque control, servo systems can also perform precise, fast, and stable position control.

 Generally, when we talk about robot servo systems, we are referring to precision servo systems used in multi-axis motion control. A multi-axis motion control system consists of a high-order motion controller and a low-order servo driver. The motion controller is responsible for decoding motion control commands, the relative motion between each position control axis, acceleration/deceleration contour control, etc., and its main function is to reduce the path error of the overall system motion control. The servo driver is responsible for the position control of the servo motors, and its main function is to reduce the following error of the servo axes. 

  The requirements for servo motors in robots are higher than the other two parts. First, servo motors must have fast response. The time from receiving the command signal to completing the required working state of the command should be short. The shorter the response time to command signals, the higher the sensitivity and the better the fast response performance of the electric servo system. Generally, the electromechanical time constant of the servo motor is used to describe its fast response performance. Secondly, the starting torque-to-inertia ratio of the servo motor must be large. When driving a load, the robot's servo motor requires a large starting torque and a small moment of inertia. Finally, the servo motor must have continuous and linear control characteristics. Its speed should change continuously with the control signal, and sometimes it needs to be proportional or approximately proportional to the control signal.

  Of course, to fit the robot's shape, the servo motor must be small in size, lightweight, and have a short axial dimension. It must also withstand harsh operating conditions, perform very frequent forward and reverse rotations and acceleration/deceleration, and withstand several times the overload for a short period.

  Servo drives are actuators that utilize the torque and force generated by various motors to directly or indirectly drive the robot body to obtain various movements. They have advantages such as a high torque-to-inertia ratio, no brushes, and no commutation sparks, and are widely used in robots.

  In the industrial sector, servo-driven robots are used on production lines to perform tasks such as tightening screws, welding, and assembly. Some factories also deploy robots for conveying and handling. With advancements in servo technology, robots performing these tasks have seen significant improvements in weld precision, production efficiency, transport speed, and stability. 

  2. Challenges and Future Development Directions of Servo Technology

  While servo technology has made significant progress, it also faces several key challenges. The most significant is the need to reduce motor failure rates to 0.1% in extreme working environments (i.e., high temperatures above 85°C or high vibrations with accelerations of 10g). Furthermore, power consumption needs to be reduced by 10-12%, and the algorithm's error suppression capability needs to be improved by 30-40%.

  Currently, researchers have made phased progress in overcoming these technological bottlenecks. Looking to the future, servo technology will be deeply integrated with the Internet of Things (IoT), artificial intelligence (AI), and big data for further optimization and development. For example, IoT technology can optimize device interconnection efficiency, AI can be used to adjust motion parameters, and big data analytics can improve robot operating efficiency.

  II. Rapid Growth in the Robotics and Servo Systems Market

  Global and Chinese Market Landscape

  While the global industrial robot sales growth rate surged from 2019 to slow down starting in 2021, the Chinese market exhibited a different trend, maintaining continuous growth momentum, indicating that the demand for industrial robots in China remains substantial.

  III. Industrial Robots and Servo Motors Advancing in Tandem

  1. China's Industrial Robot Stock and Technological Iteration

   With the upgrading of intelligent manufacturing, China, as an industrial powerhouse, is accelerating the large-scale application of industrial robots. According to incomplete statistics, China's current stock of industrial robots has exceeded 1 million units, accounting for approximately one-third of the global total.

  In the process of industrial robot technological iteration, servo motors, as core drive components, play a crucial role in achieving high-precision operations through performance improvements. By enhancing servo motor technology, industrial robots can complete more precise and efficient complex tasks, making unmanned factories a realistic prospect.

  2. Future Outlook

  The industrial robotics industry is poised to embrace broader development prospects. As the core driving force behind the evolution of robotics technology, servo control systems stand at the threshold of technological transformation and structural realignment: In the short term, high-end demand from sectors such as semiconductors and new energy will fuel sustained market growth, enhance industrial competitiveness, and secure a favorable position within the global intelligent manufacturing landscape.