From Dongfanghong-1 to Chang'e-5, China Academy of Space Technology has created many firsts in the history of Chinese spaceflight
Release 300 "stars" in 50 years (technological perspective)
Yu Jianbin's motherland, Xin Guo Ziyu
Innovator says
"We have mainly solved the problem of existence. What we will do in the future is the work of'man without me, man with me superior.' History has created the spirit of'two bombs and one star', facing the current and next tasks, and more We must inherit and promote the spirit of "two bombs and one star". I believe the younger generation will do better than us."
——Qi Fazhi, one of the main technical leaders of Dongfanghong-1 satellite of the Fifth Academy of China Aerospace Science and Technology Corporation, and the first chief designer of the Shenzhou spacecraft
"The success of the aerospace industry is the success of a team. Looking up at the stars, there are the dreams of Chinese astronauts. Today, more young Beidou people have become the main force on this journey. They are more energetic, more energetic, and more energetic. Enthusiasm and expectations for the dream of a space power."
——Xie Jun, deputy chief designer of Beidou satellite navigation system engineering of the Fifth Academy of China Aerospace Science and Technology Corporation, chief designer of Beidou-3 satellite
"Explore the mysteries of the universe hidden under the moon, and the samples taken from the lunar soil that we brought back are the most romantic gift we dedicate to the motherland. Astronauts will never stop exploring deeper and farther space."
——Wang Guoxin, Chief Designer of Chang'e 5 Drilling Subsystem, No. 529 Factory of China Aerospace Science and Technology Corporation
"The goal of building a powerful aerospace nation in the new era requires our independent innovation and hard work. my country's first Mars exploration mission will achieve Mars circumnavigation, landing and patrol through a launch mission. To this goal, all scientific researchers have worked hard day and night and made bold innovations. , Make every effort to tackle key problems, break through a series of key technologies, and help my country's deep space exploration to go further."
——Sun Zezhou, Chief Designer of Mars Rover, the Fifth Academy of China Aerospace Science and Technology Corporation
From November 24, 2020 to December 17, 2020, Chang'e-5 completed a 23-day lunar sample return journey, creating a milestone achievement in the history of Chinese spaceflight.
Coincidentally, the Chang'e-5 probe is also the 300th spacecraft developed and successfully launched by the Fifth Academy of China Aerospace Science and Technology Corporation (China Academy of Space Technology).
On April 24, 1970, the first spacecraft Dongfanghong-1 satellite developed by the Fifth Academy of China Aerospace Science and Technology Corporation, as my country's first artificial earth satellite, opened my country's first step towards the space age.
The first artificial satellite, the first spacecraft, the first navigation satellite, the first lunar probe, the first space laboratory, the first cargo spacecraft... Count 300 "stars", the first "hundred It took 41 years for “Star”, 6 years for the second “Hundred Stars”, and only 3 years for the third “Hundred Stars”.
The release of 300 "stars" in 50 years has not only created many firsts in the history of China's aerospace, but also witnessed the glorious journey of China's aerospace from scratch, from weak to strong, from a major aerospace country to a powerful one.
Chang'e 5
Truly opened the door to "return" in the target of the lunar exploration project
"Compared with Chang'e-3 and Chang'e-4, Chang'e-5 faces more uncertainty, and it really opens the door to the'return' of the lunar exploration project." said Zhang Honghua, deputy chief engineer of the Chang'e-5 probe. .
From project establishment to launch, Chang'e-5 has experienced 10 years of hard work.
The R&D team of the Fifth Academy of China Aerospace Science and Technology Corporation fully inherited the technologies of manned space rendezvous and docking, extraterrestrial celestial unmanned lander and return, etc., and united the strongest lineup of participating units to overcome difficulties, and successively broke through the moon surface sampling mission More than 20 key technologies involved.
At the beginning of the development, an unprecedented link-the launch of the lunar surface became the most difficult "hard bone", which brought a series of problems such as orbit design, takeoff measurement and control, and engine control.
In order to simulate the situation that Chang'e 5 will face on the moon as much as possible, Zhang Honghua and his team repeated experiments in the test field, accompanied by a 110-meter-high tower for 3 months.
In order to solve the problem of unsatisfactory landing posture, they have designed countless plans.
According to the engineering arrangement of the Chang'e-5 mission, a series of key links such as lunar landing, sampling, take-off, and lunar orbital rendezvous and docking will be completed in just one week. This is a huge test for the Chang'e-5 development team.
Starting from entering the launch site one month before the launch of the probe, the development team conducted 6 exercises.
"Everyone in the control hall opened their eyes wide, not letting go of any beat of the data, and when the heart touched the throat, I felt that I could jump out a little faster. Time is very tight, and everyone is running and walking. ." Zhang Honghua said.
The one-month running-in drill also gave the team a clear picture of the launch process of Chang'e-5.
At 1:59 on December 17, 2020, Chang'e-5 landed safely on Siziwang Banner in Inner Mongolia with soil taken from the moon.
"Compared with the moon sampling conducted in the last century, our autonomous obstacle avoidance soft landing and intelligent adaptive ascent have reached a new level." Zhang Honghua said proudly.
Dongfanghong One
Realize the dream of entering space
Time goes back to April 24, 1970, when my country’s first carrier rocket, Long March One, was successfully launched with the Dongfanghong-1 satellite, realizing the dream of entering space.
The Dongfanghong-1 satellite was born in a special period when the country's industrial foundation and scientific and technological level were still very backward. International friends exclaimed: "You have developed a satellite under such conditions. It is really amazing!"
Riveting is an essential process in satellite manufacturing.
During the initial prototype development and test phases of the satellite, without a rivet gun and a truss for fixing the workpiece, the developers of Dongfanghong 1 relied on a small hammer and several self-made riveting dies to knock the rivets one after another. .
From the selection of the shape of the satellite to the formulation of the structural form, from the satellite thermal control measures to the thermal vacuum simulation test, the complicated technical and technological difficulties were overcome under extremely simple conditions.
It was also very difficult to get the satellite to play the "Dongfanghong" music in space.
The developers replaced the "keys" with 6 high-stability sound source oscillators, and used the beats generated by the program-controlled circuit to control the pronunciation. After hundreds of trials, they finally ensured that the Dongfanghong No.1 played the "Dongfanghong".
"We can't hear the music played by Dongfanghong-1 satellite directly on the ground. It needs to be sent through the satellite antenna, received by the ground station, and then broadcast by the radio." Hu Qizheng, a member of the Dongfanghong-1 satellite overall team, mentioned that in order to make Ordinary radios received music from satellites, and everyone proposed this "relay" method.
Another technical hurdle is to be "visible."
To be able to see a satellite in space with the naked eye, its brightness must rise from a seventh-magnitude star to a fourth-magnitude star.
The Dongfanghong-1 satellite is only 1 meter in diameter, which makes it more difficult to "see".
In the end, the developers found inspiration from the contraction and opening characteristics of the folding umbrella, and decided to install an "observation body" made of highly reflective materials on the third stage of the launch vehicle that can be opened in space.
Because of the huge volume of this "observation body" and the extremely high brightness of the reflection, people can directly observe the satellite on the ground.
Beidou
China becomes the third country with an autonomous satellite navigation system
Autonomous and controllable are the characteristics of Beidou, but it is difficult to develop from scratch, and Beidou development is starting in groping.
The localization started with the solar panels of Beidou-1.
Afterwards, the localization research was even more difficult. Whether it was the emergence of the Dongfanghong-3 platform or the three key components that affect the life of the satellite, with the entrepreneurial spirit of self-reliance, scientific researchers overcome them one by one, and built Beidou 1 in 2003. The system makes my country the third country with an autonomous satellite navigation system after the United States and Russia.
"We are running a marathon at a speed of 100 meters." Xie Jun, chief designer of the Beidou-3 satellite, described the development rhythm of Beidou.
Many Beidou people still clearly remember the "passionate years" of the first Beidou-2 satellite development in 2007.
According to the rules of the International Telecommunication Union, frequency resources are time-limited and expired.
Time waits for no one, race against time to complete all the preliminary development, the participants did not breathe a moment after entering the launch site, followed by 200 hours of uninterrupted power-on test.
Academicians, satellite commanders, chief designers, and front-line technicians arrange shifts together to withstand various tests.
On April 16, 2007, two days after the satellite was successfully launched, the test satellite sent a clear signal. At this time, the space frequency was only less than 4 hours away.
It is also this "feat" to protect the frequency resources of my country's satellite navigation system, which opened the prelude to the construction of the Beidou regional navigation system.
The careful and meticulous style has been inherited from generation to generation.
In the development of the first set of Beidou-3 satellites, there was an episode of small errors in battery voltage.
According to the design, when the voltage difference is increased to a certain limit, the battery will automatically adjust without affecting the operation.
"Change! Don't go to heaven with any doubts." The Beidou team did not let go of this hidden danger.
Reopen the solar wing, remove the hatch, and replace the hidden battery pack.
In the end, all the work was completed in accordance with the original plan, giving the satellite another security guarantee.
During a key single-machine test of the ninth Beidou-3 satellite, the chief designer Liu Jiaxing found a key indicator exceeded.
But exceeding the standard is less than one nanosecond, that is, less than one billionth of a second, so short that it is indescribable to use "moment" or "moment".
Further investigation will add a lot of work, and the results may not be found.
But without finding out the reason, Liu Jiaxing could not pass the hurdle in his heart.
In the end, everyone analyzed and found the problem together, and the indicator returned to normal.
Shenzhou V
Milestone of China's manned space project
In 1992, the Party Central Committee formally approved the implementation of the manned space project, and then the manned spacecraft was approved. Qi Fayu was appointed as the chief designer of the Shenzhou spacecraft.
Qi Fazhen, who has been engaged in missile, launch vehicle and satellite research, was 59 years old when he received the assignment as the chief designer of the Shenzhou spacecraft. He was originally planning to retire in another year.
At the beginning of receiving the mission, Qi Fazhen frankly said, "It is indeed quite tangled inside and feels a lot of pressure." The more important reason is that "manned spaceflight, human life is a matter of life," Qi Fazhen deeply felt that the responsibility was too heavy.
At that time, China’s manned spaceflight project had established the development of spacecraft, but should the two-cabin scheme or the three-cabin scheme be used?
This multiple-choice question was placed in front of the team.
"At that time, there were two-cabin and three-cabin programs in the world, and they were all successful. Does China use a two-cabin program or a three-cabin program? There is a lot of controversy. In the end, we decided to use the three-cabin program." In Qi Fazhi's view , Combining China’s actual conditions and adopting a program that suits you, is innovation.
On November 20, 1999, my country’s first unmanned experimental spacecraft, Shenzhou-1, was successfully launched, and the spacecraft’s landing place was only 10 kilometers away from the intended location.
Recalling the most unforgettable moment in decades of aerospace, Zhang Bonan mentioned Shenzhou V without hesitation.
It was a milestone in China's manned spaceflight project and realized the Chinese dream of flying to the sky for the first time.
At that time, Zhang Bonan, who was the deputy chief designer of the Shenzhou 5 spacecraft, encountered a great test before the spacecraft left for the Jiuquan Satellite Launch Center.
Shenzhou V is my country’s first manned spacecraft, and many experts have questioned the stability of the seat buffer used by astronauts.
"Seat buffer", as the name implies, is an important tool to ensure the safety and comfort of astronauts.
The "seat" is uncomfortable, and the safety of astronauts cannot be guaranteed in the complex environment of space and when returning to land.
In line with the belief of "Astronauts, nothing is trivial", Zhang Bonan was appointed when the other personnel were already stationed at the Jiuquan Satellite Launch Center. He spent two months concentrating on key issues and finally designed and manufactured a safe, stable and reliable seat cushion. The vehicle was verified and was successfully installed on the Shenzhou 5 return capsule before the rocket was launched.