Endless Pursuit of Precision in life
-- Eulogy to Fei Yetai, Trailblazer of Precision Theory in China
By Chen Wanwan (Anhui Daily)
The clock is still ticking, but its owner is gone. Fei Yetai, founder of the Chinese precision theory and Professor of Hefei University of Technology, passed away on February 26 at the age of 82. The college teacher, who devoted 61 years to teaching, had never halted his step in pursuing “precision” in his life.
“I worked with ‘precision’ and ‘error’ my entire life.”
--Hailed as the trailblazer of Chinese precision theory, he has accomplished over 40 top-level scientific programs, won 9 minister-level awards, and addressed a large amount of difficult practical problems.
On April 20th, Fei’s students came to his office to pack his remnants. Heaps of books, documents and photos in the small room were well sorted by their masters. The room is like a portrait of his life -- constantly eliminating errors and pursuing great precision.
Professor Fei join the faculty at HFUT, where he just graduated from, in 1955. In 1959, he was transferred to the newly-established discipline of precision instrument. There was nearly no studies on precision and error at the infancy of the PRC, and Chinese products then always featured big noise, severe vibration, and high energy consumption.
With the ambition to serve the country with technology, Mr. Fei devoted himself to this area with no hesitation.
Precision instruments are extremely delicate. Even a faint tremor would sway the experimental results. To ensure the quality of the experiments, he always grabbed bites of a bread for dinner after a busy day, and stayed at the lab at night for better experimental results.
The grating meter measurer he developed in the early 1980s has broken the limits from traditional single-error modeling and correction. It is deemed a monumental achievement in China’s precision instrument discipline. On this basis, Professor Fei conducted comprehensive and in-depth studies on the application of the error theory and achieved a series of research results that comprehensively improved the error and precision theory in China.
Based on the dynamic characteristics of modern instruments, Professor Fei proposed the dynamic precision theory and the shedlike model for dynamic precision loss, and set up the system-wide dynamic error analysis modeling method. In doing so, he further disintegrated and sought the source of dynamic system loss function, analyzed the rules for precision loss in the different units of the dynamic system, and put forward the theory and method of system-wide uniform design based on equivalent loss of different units, all of which are major processes in China’s error and precision theories.
China was once embroiled in the misconception of pursing extreme precision if every mechanical part, which raised costs and resulted in unstable performance. In this context, Professor Fei took the lead in proposing that Best components do not necessarily guarantee the best performance.” Through numerous experiments, he found the rule of error transmission and thus put forward a new method which advocates optimizing grouping of components instead of pursuing absolute precision in each and every component. The method has later become an important part of China’s latest precision theory.
His precision error theory has already become the basic method of precision evaluation and the theoretical basis of precision instrument studies. The theory has been widely applied in multiple areas of China’s modernization. In 1990s, a supervisor of a satellite development institution approached Fei for technical bottleneck. Professor Fei not only solved the problem ingeniously, but also put forward the thermal error theory on this basis. China's breakthroughs in high technologies in recent years, whether the Shenzhou 10 Spacecraft or the manned submersible Jialong, are inseparable from the precision instrument discipline, in which error and precision theories and technology constitute a major role.
“I worked with ‘precision’ and ‘error’ my entire life.” Over the past 60 years, Professor Fei undertook and accomplished over 40 high-level scientific research projects, won 9 ministerial-level awards, and addressed a large amount of difficult practical problems. In 2007, he was conferred with Lifetime Contribution Award by International Committee on Measurements and Instrumentation (ICMI).
“Scientific research allows no utility”
Many people were led to the world of precision instruments by his book. Over 100 PhD and master students that he guided have grown into famous experts in this field.
After his death, despite the reiteration of his family that Fei would like his funeral handled simply, crowds of students and scholars still came to his funeral to bid farewell. More than 10 academicians from the Chinese Academy of Sciences and Chinese Academy of Engineering send condolences and wreaths.
Professor Fei published 9 books, of which his Error Theories and Data Processing published in 1981 was listed as national key textbook that opened up the field of precision instrument theories. This textbook was reprinted for six times in the past 30 years and more and was adopted by over 200 Chinese universities. The course has even been chosen as a required course for students majoring in Measuring & Control Technology and Instrumentation or the likes. The new generation of talents in instrument science all read his books before.
While pursuing precision in science, Professor Fei was always seeking precision in life. He left home for work at 7:25 every morning. He remained stringent on both students and young teachers with high standards and strict demands, both academically and morally. He even did everything himself to ensure the quality of talents. With stringent supervision from Professor Fei, his students were also under his meticulous care in personal life. Professor Fei was always concerned about his students. He would manage to win more subsidies for those students with poor family conditions and prepared refrigerator and microwave oven in the labs so that students won’t starve. He was even a middleman sometimes who introduced students to each other who finally tied the knots.
Professor Fei was still concerned about the progress of his student Miao Enming’s work before he lost consciousness. “Without his encouragement, I would not have gone that far in my studies”, said Miao.
The components in the instrument would expand with heat and contract with cold, and some of these variations my affect the normal functionality of the instrument. For a long period of time, studies on thermal errors received little attention. The theory was even questioned. But Fei, sticking to the idea that scientific research seeks no fame or attention, remain committed to his work out of his pure interest in science. Nowadays, the thermal error theory has become one of three classic directions in precision instrument discipline.
“My motto is to strive for excellence.”
Although Fei had stood at the peak of his field, he never sought any fame or profit. He is thrifty in his own life and seldom receives any gift. But a flashlight is held as precious by him. It is a gift from his student. For some period in the past, he had his office at the 7th floor. Because he always got off work late at night, he had to manage to go downstairs in darkness since lights have already been shut off on campus. At his 65th birthday, his postgraduate students sent him a flashlight as a birthday gift. This flashlight not only lit up his way home, but also reflected his lifetime principle — “sacrificing himself but lighting up the others”. Professor Fei would always bring some gifts home after he returns from his official visit elsewhere but those gifts are for the gatekeeper of the school because the gatekeeper has to get out of bed to open the door for him late in the night.
In 2008, Professor Fei retired at the age of 74. But his life remained the same: spending the day at the labs and the night at home.
In the southwest corner of the Science Building of the campus, there sits a garden with the greatest varieties of trees, each and every one of which was grown by Fei’s student. A single tree stands for one postgraduate student. To date, hundreds of peach trees, plum trees and apricot trees are in verdant luxuriance, standing as a testimony to Professor Fei’s devotion to education.
Published originally on Anhui Daily (April 24, 2016):
Edited by: Zhou Hui