电工技术学报2025，Vol.40Issue(19)：6192-6212,21.DOI:10.19595/j.cnki.1000-6753.tces.241548
机器人关节用伺服电机关键技术与展望
Key Technologies and Prospects of the Servo Motor for Robot Joints
摘要
Abstract
Intelligent robots have gained global interest over the last few years and influence global manufacturing.The optimization of robot hardware highly depends on high-performance joint actuators.Due to their high control accuracy,rapid dynamic response,and mature market,Servo motors have become the mainstream drive components for robot joint actuators.With robots continuously being proposed for high-intelligence requirements,servo motors for robot joints face new opportunities and challenges.However,the research on motor design for robot joints still lacks clear guidance and uniform standards.This paper overviews the current research progress,industry status,and emerging trends of the servo motor for robot joints,clarifying the technical route and pointing out future development. Joint actuators and servo motors can be classified based on the features of robots,as shown in Fig.A1a and Fig.A1b.The joint actuator can be classified into flexible actuators(FA),elastic actuators(EA),and quasi-direct drives(QDD)based on the type of transmission components.According to the combination architecture of transmission components,joint actuators can be classified into cascaded parallel,series coaxial,and embedded coaxial.Servo motors for robot joints include inner rotor radial flux,outer rotor radial flux,axial flux,and coreless.As shown in Fig.A1c,they can be classified into joint actuators and adopted in different robots. The inner rotor radial flux motor has evolved to the cylindric-cascaded type for micro-robots,the frameless-cascaded type for high-load,high-precision robots,and the flat-serial structure for high-dynamic,high-impact robots.It is suitable for robot joints with a diameter of 30～80 mm.The outer rotor radial flux motor has a higher peak torque density and diameter-to-length ratio,ideal for flat-serial,flat-cascaded,and flat-embedded structures.It is commonly used in direct-drive and quasi-direct-drive robots,where the flat-embedded type with a diameter of 100～180 mm is the most widely used for highly compact structures and high peak torque.Axial flux motors have short axial lengths,high torque density,and compact structure,having immense potential when applied in high-load robots,but still need to be improved in thermal design and manufacturing technology.The coreless motor has the advantages of low torque ripple,high efficiency,and fast response.It is fit for small joints with diameters of 8～20 mm,especially the robot's dexterous hands. The key design technologies for the robot joint motor include conceptual design,electromagnetic analysis with optimal design,thermal analysis with cooling design,and mechanical analysis with reliable design.With high dynamic motion and strong environment adaptability required in universal robots,the technical difficulties that need to be solved are as follows:(1)Thermal analysis and cooling design for the integrated motor drive.(2)Special motor design towards robot joints.(3)High reliable motor design under high impact loads.(4)High torque density motor design adopting new materials and technologies.关键词
伺服电机/机器人/关节执行器/电机设计技术Key words
Servo motor/robot/joint actuator/motor design technology分类
信息技术与安全科学引用本文复制引用
史婷娜,徐奕扬,谭本慷,颜冬,陈浩,曹彦飞..机器人关节用伺服电机关键技术与展望[J].电工技术学报,2025,40(19):6192-6212,21.基金项目
国家自然科学基金重点项目(52237003)和国家自然科学基金重大项目(51991384)资助. （52237003）
