Xinhua News Agency, Shanghai, February 3 (Reporters Wu Zhendong and Xu Dongyuan) swirled and rose, like a streamer dancing, turning into a raging flame at the top... The Beijing Winter Olympic Torch "Flying", which is being passed, has attracted wide attention since its debut. The reporter learned from Donghua University that the team of Professor Sun Yize of the School of Mechanical Engineering of the university is the key manufacturing technology provider of the outer streamer (shell) of the torch. For the "black technology" behind the torch, researchers use the three "highs" of "high-tech materials", "high-tech equipment" and "high-end manufacturing" to summarize.
Walking into Sun Yize's office, the winter vacation is still a hot scene. He led the Shanghai "Education Pioneer" team, which has developed special life-saving and communication ropes and cables, to help the "Jiaolong" complete the 5,000-meter and 7,000-meter deep diving tests, and this time tackled the torch shell weaving technology, and successfully put on the carbon fiber "coat" for the torch.
Researchers from Donghua University instructed on-site three-dimensional weaving. Image from Donghua University
In 2020, Shanghai Petrochemical, the overall bearer of the torch, found Sun Yize, who has been deeply involved in the field of automatic weaving equipment for many years, and threw him a problem - using carbon fiber composite materials to present the artistic modeling of the "flying" flare outer streamer with high precision. Sun Yize said that the outer streamer shape of the torch is a high-dimensional curved body, which is an extremely complex heterosexual structural part for engineering manufacturing. After repeated discussion and polishing with the designers, the team finally completed the mathematical modeling of torch manufacturing with a multidimensional surface fitting intelligent algorithm.
"Flying" torch production scene. Image from Donghua University
Modeling is only the first step. The torch shell is not as thick as above and below, and the curved surface is not the same thickness, which cannot be achieved by traditional manufacturing processes. At this time, the three-dimensional high-precision spherical three-dimensional weaving machine for large-size special-shaped structural parts exclusively developed by Donghua University has become the "secret weapon" of the special-shaped structural parts of "weaving". According to reports, its interior has a total of 576 woven spindles, which can weave a maximum cross-section of 500 × 500 mm, which is currently the world's largest three-dimensional spherical knitting machine with the largest weaving size. When the equipment is working, 576 high-speed moving spindles are constantly changing tracks in the circular spherical track, and the high-speed cross-shuttle. "It's like on a four-lane highway, hundreds or even thousands of cars cross each other at high speed. Through intelligent computing and precise orbit change control, we avoid 'traffic accidents'. Sun Yize introduced.
A three-dimensional spherical three-dimensional knitting machine developed by researchers at Donghua University. Image from Donghua University
In the production workshop, the 8-meter diameter three-dimensional spherical three-dimensional knitting machine runs at high speed, and hundreds of black tows cross each other, each containing 12,000 carbon fiber filaments. It only takes a few minutes to "weave" a torch shell that is accurate to "grams", and then through the processes of laser carving, coloring, spraying high temperature paint, etc., the entire manufacturing work of the "flying" torch shell is completed.
It is understood that in order to make the carbon fiber composite materials "obedient" in the "weaving" process, while in the industrial production of three-dimensional reduction of the streamer shape soft and flowing feeling, the scientific research team invented the so-called "eccentric" weaving method, to solve the problem of large curvature, variable density weaving; the original double robot collaborative clamping core mold control algorithm, to ensure that the large-size special-shaped structural parts "weaving" in the complex stress state of the dynamic performance of the optimal, etc., and finally realize the torch shell three-dimensional automatic three-dimensional "weaving" and automated grinding, It not only fills the domestic gap, but also leads the world.
Sun Yize said that the team will continue to take scientific and technological innovation and solve the urgent needs of the country as its own responsibility, around the "card neck" and short board problems in high-end weaving equipment, carry out basic theoretical research, break through key core technologies, and promote industrialization applications.
Editors: Ding Wenxian, Wu Bowen, Zheng Daojin, Li Yuxi (Intern)