Reducer is a key component of industrial robots
The research and development, manufacturing and application of industrial robots is an important symbol to measure the strength and level of a country's scientific and technological innovation and high-end manufacturing. Industrial robots are mainly composed of three core components: reducer, servo motor and control system. Precision reducer is the most critical functional component in industrial robots, and it is also one of the bottlenecks restricting the development of China's robot industry.
"For example, if an industrial robot is regarded as an adult's arm, the reducer is the joint of the arm." Wang Jiaxu said that the reducer is an intermediate mechanism connecting the power source and the actuator, and has the function of matching the speed and transmitting torque. Industrial robots require high-intensity repetitive motion, and the quality of the joints determines the accuracy, reliability and service life of the power transmission and motion transformation of industrial robots. In the total cost of the robot, the cost of the reducer accounts for more than 30%.
Industrial robot joints are mainlyRV ReducerHarmonious wave reducer two kinds. For a long time, the RV reducer was once monopolized by Japan's Nabotsk company, and the harmonic reducer was once monopolized by Japan's Hamenaco company, which seriously restricted the industrial development of domestic industrial robots.
Wang Jiaxu, who has dealt with mechanical transmission all his life, has always been famous for his daring to break through and fight. Facing the precision reducer urgently needed for the development of domestic robots, he has been engaged in the research of reducer. In 2005, he led the team to start scientific research, aiming at the highly reliable precision harmonic reducer.
Wang Jixu said that the harmonic reducer has the advantages of small size, light weight, high transmission ratio, and high precision. It occupies a dominant position in the field of light-load precision reducers. However, the technical barriers of the harmonic reducer are high. Independent research and development and localization must break through the key technical bottlenecks in tooth design, materials, processing technology, test evaluation, etc.
Improve the core competitiveness of robots in China
In the State Key Laboratory of Mechanical Transmission, the reporter saw the application of a robot with a harmonic reducer independently developed by Chongqing University. "It has been running here for 6000 hours, and its accuracy and service life have reached the level of similar robots in Japan." Wang Jiaquo explained that the harmonic drive transforms the gear indexing circle into an ellipse through the deformation of the thin-walled flexible wheel to realize multi-tooth meshing, thereby improving the high precision, rigidity and bearing capacity of the transmission.
The high elastic deformation characteristics of the flexible wheel of the harmonic reducer make the precise design and modification of the meshing tooth profile very difficult, the tooth surface is easy to wear, and the accuracy retention is poor. In addition, the flexible wheel processing technology is poor, and fatigue fracture is easy to occur under the cyclic alternating stress, which also makes the regulation between high precision and high rigidity and high reliability become a prominent contradiction. Therefore, the principle of harmonic drive to achieve multi-tooth meshing puts forward very strict technical requirements for the design and manufacturing process, which is also the main reason for restricting the performance improvement of domestic harmonic reducer.
In view of the above problems, Wang Jiaxu led the team to aim at the frontier of discipline development according to the major national demand. On the basis of long-term solid research, through multi-disciplinary innovative and optimized design research such as meshing principle, interface mechanics, transmission tribology, system dynamics and material science, the design, manufacture, test and evaluation technology of precision harmonic reducer were systematically conquered, the design, analysis and test evaluation system of arc tooth profile harmonic drive driven by conjugate parameters is established, and a full series of high-reliability and precision harmonic reducers of short cup, ultra-short cup and top hat type are successfully developed.
The annual production scale of more than 30000 sets of harmonic reducers has been formed, and the sales scale of nearly 10000 sets of harmonic reducers has been completed. High-reliability precision harmonic reducer products have been widely used in industrial robots, satellite pointing mechanisms, scanning mechanisms, deployment mechanisms, control moment gyro and other space mechanisms, as well.Droneand other equipment.
After acceptance by the expert group, the project has overcome the design, manufacturing, testing, test evaluation, and key common technologies such as product reliability and consistency in the process of mass production and assembly of harmonic reducer, the core basic component of industrial robots. A robot harmonic reducer with high precision, high rigidity, high reliability, long life, high efficiency, low noise, and high power density with independent intellectual property rights and reaching the international advanced level has been formed.
In order to improve the independent innovation ability of Chinese enterprises, improve the technical level of domestic industrial robots in a large span, enhance the core competitiveness of China's industrial robots, and meet the major needs of China's advanced manufacturing and strategic emerging industries for the industrialization of domestic robots.
