Which high-tech to help the Beijing Winter Olympics

[Global Times reporter Fan Wei Global Times special correspondent Chen Shan] Modern sports competition has long been inseparable from the help of high technology, especially in this Beijing Winter Olympic Games. From daily training to competition equipment, even to athletes' gloves and even the bending angle of ice blades, they all shine with the most cutting-edge scientific and technological power of the times.

The aerospace technology behind China's Winter Olympic gold medals

On the evening of February 5, the Chinese short track speed skating mixed team composed of Fan Kexin, Qu Chunyu, Zhang Yuting, Wu Dajing and Ren Ziwei took the lead in crossing the finish line with a time of 2:37.348, winning the first gold medal at the Beijing Winter Olympics for the Chinese team. On the short track speed skating track that pursues the ultimate human speed, the victory and defeat are in the milliseconds. This requires not only the state, will and tacit understanding between the athletes, but also the grasp of details - in the high-speed short track speed skating, the athlete's movements and slight changes in posture can affect the speed.

According to the Global Times reporter, behind the gold medal of China's short track speed skating, there is a training "artifact" that helps athletes to reduce wind resistance as much as possible in a perfect posture - wind tunnel. In 2019, the State General Administration of Sport and the Eleventh Academy of Aerospace Science and Technology deepened cooperation, and the three institutes of the Eleventh Academy of Aerospace Science and Technology designed and built the first sports wind tunnel in the mainland. Wang Kaiwen, secretary of the party committee of the institute, said that this sports wind tunnel was completed in 2020, the caliber of the wind tunnel is 2.5 meters wide, the height is 3 meters, the length of the test section is 8 meters, and the wind speed is equivalent to a strong typhoon of 14 levels.

Zheng Liu, an engineer of the three institutes of aerospace science and technology who participated in the design of the wind tunnel, told the Global Times reporter that when designing the sports wind tunnel, the designers investigated a large number of Winter Olympic sports projects, and finally determined the length, width and height of the wind tunnel after comprehensively considering the size of various Winter Olympic sports equipment such as snowmobiles, sleds, and skis, as well as the size of sports equipment for some Olympic sports. The wind speed of 151.2 kilometers per hour is also considered that the fastest snowmobile project in the Winter Olympics has a maximum speed of about 150 kilometers per hour, which can fully meet the test training requirements of all Winter Olympic sports.

Since the sports wind tunnel is mainly used for athletes who race against the clock, its requirements for accuracy, safety and comfort will be higher than that of military wind tunnels. Li Yuqiu, a researcher at the Military-Civilian Integration Division of the Eleventh Academy of Aerospace Science and Technology and a member of the expert team of the sports comprehensive training wind tunnel, said that every athlete who walks into the wind tunnel is our 'national treasure'. In order to ensure their safety, the sports wind tunnel has deliberately enhanced safety measures, such as trying to avoid the use of screws and other fasteners that are easy to fall off inside the wind tunnel, so as not to fly out and hurt people; reasonable protective nets around the test platform, which do not interfere with the test and prevent athletes from slipping; and add an emergency stop button next to the coach accompanying the test, so that you can stop immediately in case of emergency.

In addition, in order to facilitate the screening of sports postures, the sports wind tunnel also has a shooting storage function, which can store the force measurement data, picture data and the change of center of gravity after the athlete's posture change at a time point to provide reference for coaching guidance. Athletes can also see their own movement test data in the display on the floor in front of them.

Li Yuqiu told the Global Times reporter that the United States, Japan, Sweden and other Western countries have applied wind tunnel technology to the daily training of athletes in the last century, and the mainland's application in this regard started late, but thanks to the rapid development of continental aerospace technology, the current mainland's sports wind tunnel technology has completely caught up with Western countries.

What's the magic of sports wind tunnels? Zheng Liu told the Global Times reporter that taking the Winter Olympics racing project as an example, the wind tunnel is mainly used to provide experimental help for reducing the wind resistance of athletes. The smaller the wind resistance, the faster the speed, and the less physical energy the athlete consumes. Zheng Liu said that when the test is carried out in the wind tunnel, the athlete will stand or hang on the six-component sensor designed in combination with the characteristics of the sports project, when the wind created by the wind tunnel is blown head-on at a wind speed equivalent to the athlete's movement speed, the change in resistance under different action postures can be measured through the six-component sensor, "For example, in the speed skating project, the athlete bends slightly, or changes the gesture, the change of resistance can be measured by the six-component sensor under the foot, and then the change data will be displayed on the electronic screen. Athletes and coaches will know which action will achieve the least wind resistance. ”

"Another example is the test of ski jumping, athletes will be hung on a three-degree of freedom suspension force sensor, with the change of the angle of the snowboard under the foot, and the change of the angle of the instep tightening, the change in wind resistance caused by it can be accurately measured." With this system, you can find the air posture with the least wind resistance. After locking in the movements and postures with minimal wind resistance, the athlete can form muscle memory after long-term reciprocating training. ”

Li Yuqiu told the Global Times reporter that the force sensor in the sports wind tunnel can measure the change of 0.1 cow, and the resistance effect brought by any small change of the athlete can be accurately measured, "Our purpose is to find the best sports posture for the athlete, produce the minimum resistance, and improve his speed." ”

According to the calculations of relevant professionals, if the air resistance can be reduced by 10%, the performance of athletes can be improved by 1%, and in the Olympic arena where milliseconds must be contested, the gap of 1% or even 1 ‰ may determine the outcome of the race, and in the steel frame snowmobile event of the 2018 Pyeongchang Winter Olympics, the gap between the first and sixth place in the men's event is only 1.2%. The sports wind tunnel's precise control of details will allow athletes to win the small.

Domestic snowmobiles get rid of external dependence

In fact, wind tunnel technology is also widely involved in the daily training of Chinese Winter Olympic athletes. Jia Yi, deputy director of the seventh room of the second institute of the Eleventh Academy of Aerospace Science and Technology, revealed that the national snow team used a specially customized snowmobile in the run-in training. According to reports, the previous national snow team's race car not only depends on imports, but also can not buy the best performance of the one, and the foreign competition snow car is tailored according to the athletes' own characteristics, even if we can buy, it is just an ordinary shelf model, the performance is greatly reduced. Therefore, the domestic snowmobile developed by itself this time adopts high impact carbon/glass hybrid composite materials, and adopts the integrated design of low wind resistance and high reliability of the shape structure. With years of experience in designing missiles and aircraft, designers use aerodynamics to design the basic shape of the snowmobile, and then continuously optimize the shape and basic components through simulation calculations and low-speed wind tunnel tests. Promote the domestic snowmobile equipment from "none" to have, filling the domestic gap.

In addition, there is an ice and snow sports training equipment "modified" from the engine of small missiles and drones, which has been successfully applied to the daily training of cross-country skiers. The designer said in an interview with the Global Times reporter that this set of aerodynamic principles based on the reverse thrust of the fan exhaust air, and the design and development of the bypass fan jet power booster, according to the needs of training, for cross-country skiers to provide auxiliary thrust, so that athletes can break through their own physical energy limitations in training, carry out various extreme state training activities.

It is understood that when this booster is used, athletes only need to wear components to fix the booster weighing about 3.5 kg on the back and assist in training under the impetus of the power device. The thrust control device of the booster has a manual control function, which can artificially control the thrust size and start and stop of the booster in real time, so as to practice technical actions such as turning, lane change, jumping and so on in the high-speed state, so that the athlete can break through the physical limit and form muscle memory at high speed.

High-tech equipment "from head to toe"

"You can compete in the Summer Olympics with almost no personalized equipment, but the Winter Olympics is another matter, and your results often depend on your equipment." When introducing the role of high-tech equipment in athletes achieving good results in the Winter Olympics, this statement of the Washington Post on the 5th may be somewhat "only equipment", but it is undeniable that the Winter Olympics is not only a challenge to the competitive ability of athletes, but also a test of the high-tech capabilities of various countries.

The report takes Santos, the top short track speed skater in the United States, as an example, saying that she is armed with high-tech equipment all over her body: the short track helmet she wears resembles a streamlined bicycle helmet, which minimizes air resistance; in order to prevent the impact of flying ice chips, she also wears high-performance goggles. In short track speed skating competitions, due to frequent contact between players, the main body of the glove is white, which is convenient for the referee to better judge the penalty. Santos opted for professional gloves made of cutting-resistant materials, and the tip of the left glove was made of carbon fiber to help her control her friction with the ice surface when cornering.

The athletes' clothing is even more exquisite. Inside Santos' tracksuit, he also wears a set of skinny jumpsuits that provide cut protection. "We use ice knives to skate, it's not uncommon for someone to be cut, wearing such a cut suit, even if someone is cut by an ice knife, it can greatly reduce the severity."

"Nihon Keizai Shimbun" said on the 6th that the surface of the alpine ski suit worn by Japanese athletes has added a longitudinal groove, and the relevant person in charge, Miyashita Seiki, said that "the development inspiration comes from the skin of dolphins." Alpine skiing at high speeds is susceptible to air resistance, while dolphins swim with uneven skin changes to reduce water resistance, he said. The alpine ski suit used in the Japanese team uses a material that can appear bumps and bumps with muscle movements. The skating suits worn by Japanese women's speed skaters use a non-extendable material that is polyurethane film attached to the knitted fabric, which makes it easy to maintain a forward-leaning posture when wearing, thereby reducing air resistance. It is said to reduce air resistance by about 3% compared to similar products from the last PyeongChang Olympics.

The Chinese short track speed skating mixed team that has just won the gold medal is also armed with high technology. For example, the short track speed skating race suits they wear are designed by ANTA and have the lightest and most breathable level in the world. This sportswear adopts the latest 360-degree full-body anti-cutting technology, breaking through the traditional local protection, greatly improving safety, and also has the characteristics of high strength and lightness, and the strength is 15 times that of steel wire. The whole set of clothing adopts advanced air turbulence control drag reduction and boundary slip drag reduction technology, and uses a special-shaped structure on the surface of the garment to quickly divert air. Compared with ordinary skating suits, the resistance reduction is increased by 5%-10%. Improved from the original double-layer structure to a single layer of full-body anti-cutting, which can reduce the weight of athletes. Therefore, this set of equipment that fights air resistance and can help team members reduce air resistance in the speedy game can be called "ice shark skin".

The unique equipment such as ice knives and skis of the Winter Olympics is full of mystery. Santos' ice knife boots are said to be handmade from specialty materials such as carbon fiber, microfiber, and it bends slightly to the left — because skaters only turn left. The degree of blade bending of each athlete is tailored to the individual, and the specific data is kept strictly confidential. The blade used in figure skating has been changed from steel to carbon fiber, making it easier to steer quickly. Similar situations occur in projects such as cross-country skiing. According to the report, the bottom of the ski needs to be waxed to increase the speed of skating, but how to apply wax needs to be based on the weather conditions of the day, and the professionals need to formulate a plan to ensure the best competition effect.