Since ancient humans made the first stone tools by tapping and grinding, the progress of manufacturing technology has always been accompanied by the progress of human civilization. In recent years, with the rapid development of science and technology and the needs of people's livelihood and national defense construction, all countries have vigorously developed the manufacturing industry. As an indispensable key processing means in the development of cutting-edge technology, ultra-precision manufacturing has great demand for both military industry and civilian industry.
In the view of Zhang He, associate professor of the School of Electrical Engineering and Automation of Harbin Institute of Technology, China's equipment manufacturing should move from the low-end to the high-end, first of all, it is necessary to solve the manufacturing quality problem, and the core key is to solve the problem of ultra-precision manufacturing capabilities. Especially in recent years, China's satellite, military, medical and many other fields, have formed a strong, stable and large-scale demand for precision ultra-precision processing; precision ultra-precision manufacturing is at the high end of the value chain, the development of precision ultra-precision manufacturing is a powerful means to crack the key technology "card neck" of other countries on China's major domestic equipment.
In this context, Zhang He is fully committed to the research work of ultra-fine positioning plane motors, linear motors, magnetic levitation gravity compensation and other related fields. In this scientific research direction that few people are involved in, he is willing to become a screw in the development of ultra-precision manufacturing in the country, and use scientific research practice to help the development of the "precision" cause of the motherland.
Zhang He
<h1 class = "pgc-h-arrow-right" > move forward steadily and firmly in the direction of life</h1>
The development of precision ultra-precision equipment manufacturing industry is a historical opportunity for the country to promote industrial transformation and upgrading. Zhang He's association with research in this field is also closely related to the background of national development.
At the beginning of the 21st century, the development of China's manufacturing industry was surging. At that time, Zhang He, who graduated from high school, was admitted to Harbin Institute of Technology (Weihai) majoring in electrical engineering with excellent results. In the four years of university, he continued to take root and study in this major, and when he graduated, he was sent to Harbin Institute of Technology headquarters to pursue a master's degree in electrical engineering.
Because there has always been a strong interest in the direction of motors, and the discipline of electrical machinery and electrical appliances is also the only key second-level discipline approved by the state under the first-level discipline of electrical engineering of HIT, therefore, after graduating from graduate school, Zhang He is determined to continue his doctorate in electrical and electrical disciplines at Harbin Institute of Technology. At this stage, Zhang He successfully entered the research group engaged in motor research. In the process of learning and exploration, he has a deeper understanding of linear motors, flat motors, etc., and with the establishment of major scientific and technological projects in related fields, he actively devotes himself to the research in this field.
During his doctoral period, Zhang He mainly explored the "basic research of multi-degree-of-freedom magnetic levitation micro-motion station". Under his introduction, the reporter learned that the multi-degree-of-freedom magnetic levitation micro-motion table has the advantages of high positioning accuracy, fast response speed, frictionlessness, compatible with vacuum environment, etc., and has broad application prospects in the field of modern precision and ultra-precision equipment such as semiconductor lithography system, ultra-precision measurement, and biochip technology.
In this direction, Zhang He put forward an integrated magnetic levitation micro-dynamic platform scheme on the basis of summarizing the advantages and disadvantages of the existing micro-motion station structure at home and abroad, which combines the Lorentz flat motor with the magnetic levitation gravity compensator, which has the characteristics of compact structure, high thrust linearity, good vibration isolation performance, low surface temperature rise, etc., and the related work lays a theoretical foundation for the optimization analysis of the force characteristics of the follow-up micro-motion station and the summary of electromagnetic design methods. For his outstanding research results, his doctoral thesis "Basic Research on Multi-degree of Freedom Magnetic Levitation Micro motion station" has also won the honor of "Harbin Institute of Technology Excellent Doctoral Dissertation".
<h1 class="pgc-h-arrow-right" > explore and attack, based on the needs of the country</h1>
High-end manufacturing equipment such as lithography machines and high-end CNC machine tools belong to the field of high-end technology, and in recent years have been blocked by foreign countries, which seriously restricts the development of China's integrated circuit industry and high-end manufacturing industry. "In fact, the background of our research is to face some high-end manufacturing equipment for ultra-precision positioning, especially in the research and development of lithography machines, linear motors, flat motors, magnetic levitation vibration isolation, etc. are the core technologies involved in its key subsystems." Zhang He said. And this direction of research is where their team's strength lies.
In 2016, Zhang He and his team proposed a new magnetic levitation gravity compensator based on the principle of positive and negative stiffness offset based on the specific needs of the ultra-precision microformer in terms of vacuum compatibility, vibration isolation performance and surface temperature rise according to the specific needs of the ultra-precision microlithography machine in terms of vacuum compatibility, vibration isolation performance and surface temperature rise of the National Natural Science Foundation of China Youth Foundation of China. Through this project, they studied the design method of this type of magnetic levitation gravity compensator, formed a theoretical analysis method and optimization design criterion for low-stiffness magnetic levitation gravity compensator, and laid a theoretical foundation for its practical application in related fields.
With the increasing development of semiconductor manufacturing, ultra-precision measurement and other fields, the vibration isolation performance of high-end instruments and equipment has put forward higher and higher requirements, mainly reflected in large bearing capacity, low temperature rise loss, high vacuum compatibility, etc., making the traditional contact vibration isolation technology difficult to apply.
On the basis of the research results of the National Natural Science Foundation of China Youth Fund Project, Zhang He has carried out a series of continuous studies without stopping, and successfully applied for the National Natural Science Foundation of China project "Research on Quasi-zero Stiffness large load low-power magnetic levitation vibration isolation system", which was continuously funded by the National Foundation of China.
In this project, Zhang He's team focused on key technologies such as accurate modeling of magnetic flotation springs and quasi-zero stiffness mechanism analysis, explored reasonable perception system layout schemes and control strategies, and proposed a comprehensive design method for large-load low-power magnetic levitation vibration isolation system. Relevant scientific research achievements are of great practical significance to fill the domestic technology gap and break the foreign technology blockade. In addition, the in-depth study of large-load low-power magnetic levitation vibration isolation technology can also provide technical support for other scientific and engineering fields such as large-scale space environment ground simulation devices and microgravity experimental platforms.
The continuous intake of fresh scientific research energy is the source of Zhang He's scientific research vitality. In recent years, he has also given full play to the strengths and potential of the team, carried out multi-channel international cooperation and exchanges, and achieved a series of results. In an international cooperation project he presided over, he and the research team proposed a circular winding structure vernier permanent magnet linear motor, which greatly improved the thrust density of the linear motor, while weakening the thrust fluctuation of the linear motor, which has great theoretical research value and broad application prospects.
Teach students the operating principles and test methods of linear motors
<h1 class= "pgc-h-arrow-right" > is not afraid of challenges and is determined to move forward</h1>
The development of precision ultra-precision manufacturing industry is the demand of the times, and it is also Zhang He's choice without regrets. Although the research on ultra-fine positioning planar motors, linear motors, magnetic levitation vibration isolation and other directions does not belong to the current hot direction, when the initial research was carried out, there were very few references, and Zhang He and his scientific research team members also spent a very difficult period. But all along, Zhang He has always believed that this is a necessary test for engaging in scientific research. "Researchers sometimes have to sit on the cold bench, especially in those research directions that are rarely involved, and some people need to be able to take the first step and explore the way for future generations, and I am willing to be the person who studies this direction at the beginning." Zhang He said.
Along the way, it is precisely with this spirit of daring to be the first and daring to explore that Zhang He has achieved a series of achievements on the road of scientific research. Engaged in scientific research for many years, Zhang He, as the person in charge or the main participant, has undertaken more than 10 scientific research projects such as the National Science and Technology Major Project and the National Natural Science Foundation of China, and published more than 40 articles on related achievements; authorized more than 40 Chinese invention patents and 2 international invention patents; won the second prize of the Technological Invention Award of the Outstanding Achievement Award for Scientific Research in Colleges and Universities, the Best Paper Award of the International Conference on Electrical Machinery and Systems, the Best Poster Award of the International Magnetic Congress, and more than 10 honors and awards. Selected into the Heilongjiang Provincial Young Talents Program and the Hitachi University Of Technology Young Top-notch Talents Program. Over the years, they have also established friendly cooperation with Shanghai Microelectronics Equipment (Group) Co., Ltd. and made a series of scientific research contributions to the development of domestic lithography machines.
In order to cultivate more new scientific research forces for the research field, Zhang He also spends a lot of time on the cultivation of students. Zhang He believes that today's post-90s and post-00s students are more active in their thinking and have their own opinions, compared to restricting them with "stereotyped" scientific research methods, it is better to let them exert their subjective initiative, give them more space to develop their scientific research interests, and cultivate their ability to independently conduct scientific research. All along, Zhang He has always played a role of communicator and leader, escorting students on the road of scientific research.
In Zhang He's view, doing scientific research not only requires perseverance and patience to endure loneliness; it is also necessary to be ambitious and constantly forge ahead. Looking forward to the future, he will continue to face the major needs of the country, carry out research on ultra-fine positioning flat motor, linear motor, magnetic levitation vibration isolation technology, etc., cooperate with enterprises, truly realize the transformation of scientific research technology, and turn his scientific research ideals into a touchable reality step by step.