At 19:41 on April 20, China's first Long March 7 remote-2 rocket carrying the "tianzhou-1" cargo ship was successfully ignited and lifted off at the Wenchang launch site in Hainan, starting to carry out the space flight mission for more than five months. During the mission, the cargo spacecraft and tiangong-2 will conduct three rendezvous and docking, which is the first time in China's aerospace history. The main purpose of the third rendezvous and docking is to verify the capability of the cargo spacecraft, the technology of circling to forward docking and the technology of autonomous rapid rendezvous and docking.
Ziguang IC international city officially signed a contract with Chengdu, with a total investment of no less than 200 billion yuan; one
After more than a day's flight, the automatic rendezvous and docking with tiangong-2 space laboratory was successfully completed at 12:23 on April 22. This is the first rendezvous and docking between tiangong-2 and a cargo spacecraft since it was launched into orbit on September 15, 2016.
Ziguang IC international city officially signed a contract with Chengdu, with a total investment of no less than 200 billion yuan; two
Russian satellite network quoted the editor in chief of aviation Panorama Magazine Sergei filipinkov, an expert at the Moscow Institute of Aeronautics, said: "China is following the path taken by the Soviet Union. But The airborne equipment is much better, and the digital technology adopted has great prospects in the field of unmanned and manned spaceflight. There are also some problems. When solar flares occur, ionizing radiation exists in space, and even electronic equipment in low earth orbit will be damaged. If China already has such a reliable microchip structure that can be protected from ionizing radiation, then this will be a big step forward. And Russia has just had such a plan. " This means that in the next ten years, the development and application of China's space station, the only space city in the world, is entering the fast lane.
According to the statistics of Jiwei network, many design and application technologies from China chip have been applied in the "tianzhou-1" mission. Let's get to know. (if there is any omission, please add.) according to the Beijing Morning Post, in order to drive the independent development of components, accelerate the realization of independent control of components, and verify the key components used in the space station in advance, tianzhou-1, as a flight verification platform, has used seven major types of domestic newly developed core components for the first time, firmly grasping the key lifeline of the future space station construction.
The digital signal transmission module in "tianzhou-1", more than 70 sensors of more than 10 kinds, multiple groups of optical cables and optical fiber connectors, the first domestic microwave transmission terminal and housing with a frequency of 40GHz, and the first successfully developed 100VDC / DC power supply and EMI filter are all developed and provided by China Electronics Technology Group. At the same time, among the electronic control systems in the propulsion cabin and cargo cabin of tianzhou-1, the radiation hardened 1553B bus controller developed by CETC has also been applied in the data management subsystem of tianzhou-1.
According to Luo Hong, an expert of digital optical module of CETC, "the digital optical module is like the human nervous system, controlling the transmission, transmission and reception of data. For example, the image data collected by the spacecraft from the space, the communication between the ground console and the spacecraft, and the sensing data during the docking are all completed by the digital signal transmission optical module." It is reported that in the past, spacecraft usually used copper cables to transmit signals. However, the development of spacecraft has been restricted due to the shortcomings of large size, large weight, short transmission distance, low transmission rate and poor anti-interference capability. "In the future construction of the space station, due to the rapid increase of data throughput, the space station will be overwhelmed without the use of digital signal transmission optical modules."
Luo Hong said that compared with the traditional copper cable transmission system, the digital signal transmission optical module has the advantages of reducing the weight to one tenth of the original one, reducing the volume by one fifth, increasing the transmission rate from the megabit level to the Gigabit level, and achieving the space radiation resistance capability to the high rail operation capability. It has realized the product's radiation resistance, miniaturization, strong temperature adaptability, high sensitivity and high-speed performance, Successfully solved the design requirements of small volume and small weight of the signal transmission equipment of the space vehicle, improved the signal transmission rate, effectively improved the signal transmission performance of the space vehicle, and reliably guaranteed the operation of the space vehicle.
Among the electronic control systems in the propulsion cabin and cargo cabin of tianzhou-1, the radiation hardened 1553B bus controller developed by CETC has been applied in the data management subsystem of tianzhou-1 to realize reliable transmission of data commands and effective control of some equipment, just like part of the "neural network" of tianzhou-1, sending out numerous branch data commands to realize data communication of various nerves and organs, Complete various actions of Tianzhou together. In view of the weak and sensitive units such as memory and trigger in the chip, the group has carried out the radiation resistance reinforcement design at the logical level, and has also carried out a separate full custom design in the layout design, achieving the ultimate anti total dose capacity reaching the international advanced level.
At the same time, tianzhou-1 is equipped with more than 70 sensors, multiple groups of optical cables and optical fiber connectors, which are 100% of the key "neurons" independently developed by the group, and the core devices can be controlled independently. Among them, sensors are all over the spacecraft's thermal control, propulsion, environmental control and life insurance subsystems. The supporting types include pressure, temperature, humidity, oxygen, carbon dioxide, ion smoke, differential constant temperature and other sensors, which can realize environmental monitoring and control and flight attitude adjustment. The optical cable and optical fiber connector are used for the communication interconnection of the optical path between the optical transceiver and the optical detector and the high-speed bidirectional transmission of data, so as to ensure the stability and reliability of data transmission during the orbital operation of the spacecraft.
In addition, the group developed the first domestic microwave transmission terminal and shell with application frequency of 40GHz, and successfully developed 100VDC / DC power supply and EMI filter for the first time, which raised the bus voltage of the spacecraft in tianzhou-1 to 100V, effectively improving the load capacity and overall power supply efficiency.
At the same time, tianzhou-1 is equipped with more than 70 sensors, multiple groups of optical cables and optical fiber connectors, which are 100% of the key "neurons" independently developed by the group, and the core devices can be controlled independently. In addition, the group developed the first domestic microwave transmission terminal and shell with application frequency of 40GHz, and successfully developed 100VDC / DC power supply and EMI filter for the first time, which raised the bus voltage of the spacecraft in tianzhou-1 to 100V, effectively improving the load capacity and overall power supply efficiency.
It is understood that the use of laser rendezvous and docking radar and optical imaging sensors is the key to the successful rendezvous and docking between tianzhou-1 cargo spacecraft and tiangong-2. These two core components developed by China Electronics Technology Group ensure that the two high-speed aircraft can be more quickly and reliably connected.
The two aircrafts have to chase for hundreds of thousands of kilometers in space and finally complete the precise docking. This process is likened to "threading a needle and a thread" by astronauts. Through many experiments and efforts of relevant units, China's rendezvous and docking equipment has broken through a number of technologies, and its performance is obviously superior to that of similar international products and is at the international leading level.
"During the docking process, the flight speed of the two aircraft is 7.9 km / s. to complete the orbit docking and rapid rendezvous and docking at such a speed, it requires the lidar to always maintain a wider viewing angle and higher precision measurement and tracking." According to Qu hengkuo, chief lidar engineer of CETC, the lidar cooperation target developed by CETC is carried on tiangong-2, and the lidar host and information processor are carried on tianzhou-1. The basic process of its detection is that the laser beam is emitted by the laser radar system installed on the spacecraft. After the laser beam is irradiated on the tiangong-2, the return signal is returned. The laser radar system then calculates and analyzes the received return signal. "The lidar cooperation target carried by tiangong-2 is equipped with a special glass prism, which can reflect the light signal of the lidar from multiple directions and a large range, and cooperate with the lidar to complete the measurement of flight parameters such as distance and angle, so as to ensure the accurate docking of the spacecraft."
Finally, under the same volume, weight and power consumption, the working range of CETC's lidar is more than twice that of foreign similar products, and high-precision measurement and tracking in the whole range are realized.
Tiangong-2 and tianzhou-1 have to go through hundreds of thousands of kilometers of chasing in space to complete the precise docking like a needle and a lead. During the whole process from the distance of 150m between them to the final completion of the precise docking, there is an optical imaging sensor known as "sensitive eye". This equipment can make the two high-speed aircraft more quickly and reliably dock together.
Liu Zhiqiang, senior engineer of China Electronics Technology Group Corporation, introduced that "the navigation and positioning laser information source is a key component of the optical imaging sensor. Even if it is dark in space, it can emit laser light, find the target in the dark, and transmit information; even when facing the direct light of the sun, it can also emit dual wavelength laser light brighter than the sun, so as to ensure that the 'eyes' are not damaged and find the target."
"In this space mission, the laser information source is facing multiple tests such as long in orbit time, many times of use, fast docking speed and docking in the sunshine area. The docking accuracy must be accurate to the millimeter level. It can be said that the docking is very difficult." Based on this, the project team of CETC carried out a brand-new design of product principle and process in combination with the actual application of aerospace within a limited time, and conducted complete and sufficient environmental tests. After more than 2000 tests, the third generation product was finally developed. It has higher reliability, lighter weight, smaller volume, lower power consumption, high radiation resistance and strong heat conduction capacity. The main technical indicators have reached the international advanced level. And this process is difficult.
In the rendezvous and docking mission of "tianzhou-1" cargo spacecraft and "tiangong-2", the launch command center can grasp the operation of "tianzhou-1" cargo spacecraft and "tiangong-2" at any time through the Space-based TT & C communication system built by the wide beam relay TT & C system developed by the aerospace 513 Institute, and send instructions to the spacecraft to ensure the implementation of the mission.
According to Zhang Ju, the designer in charge of the "tianzhou-1" wide beam relay TT & C terminal of aerospace 513 Institute, in the past, due to the relatively narrow communication channel, when the spacecraft adjusted its attitude for docking, separation and other technical actions, it was very likely to have signal interruption with the relay satellite. The biggest advantage of the wide beam relay TT & C system is that it has a large measurement and control coverage and can achieve a wider range of relay TT & C. At the same time, the in cabin radiation environment measurement load developed by the Shandong aerospace space load center of the 513 Institute of Aerospace Science and technology will carry out particle radiation environment detection and component radiation effect monitoring, and "diagnose" the "physical condition" of relevant components after undergoing the space radiation test.
According to Liu Jinsheng, the technical director of the particle detection group of the Shandong aerospace space load center of the 513 Institute of Aerospace Science and technology, the radiation environment measurement device in the cabin can measure the radiation environment in space and the normal working state of the components in the space radiation effect, judge whether the components can operate stably in space, and ensure that the cargo spacecraft and other spacecraft can successfully complete the original objectives.
In addition, the on-board computer products developed by aerospace 513 Institute have been applied to multiple subsystems of the spacecraft, playing a key role in the stable operation of each system.
The tianzhou-1 cargo spaceship weighs 13 tons and is mainly composed of two compartments: cargo compartment and propulsion compartment. The propulsion compartment is responsible for the general assembly of Shanghai Aerospace Technology Research Institute of China Aerospace Science and Technology Corporation, which provides power, energy and communication functions for the aircraft and propellant replenishment services for the space station.
According to Jin Zongxiang, an expert of the docking mechanism of Shanghai Aerospace Technology Research Institute, the "tianzhou-1" is much heavier than the manned spacecraft. Compared with the docking mechanism on the manned spacecraft, the docking mechanism on the cargo spacecraft has added some buffer devices, and the controller and driver have been upgraded accordingly. The second generation docking mechanism must adapt to the docking of 8-180 tons in various tonnage and modes in the future construction stage of the space station, including eccentric docking, which will generate huge docking energy, and put forward high requirements for the buffering energy consumption capacity of the docking mechanism, which is also a technology that must be broken through in the construction stage of the space station. The designers of Shanghai Aerospace put forward the idea of controllable damping control through a large number of technical research and scheme demonstration. This design meets the requirements of this and subsequent tasks through full coverage assessment measures such as controllable damper single machine product, improved transmission buffer docking mechanism product and subsystem level complete machine and buffer.
Another important task of "tianzhou-1" is to "refuel" in the air. After completing the rendezvous and docking with tiangong-2 and entering the combined flight mode, the supplementary drive of the propulsion system will carry out the test and verification of the supplementary function in the six-month space laboratory mission. During the flight of the assembly, the propulsion control driver developed by Shanghai Aerospace Technology Research Institute will execute the command of the control system, control all engines and pipeline valves, and control the attitude and orbit of the assembly.
Dai shoulun, President of Shanghai Aerospace Technology Research Institute, told the reporter that in reviewing the 13 launch missions of shenzhou-1 to shenzhou-11, Tiangong-1 and tiangong-2, all the missions undertaken by Shanghai Aerospace have achieved complete success. In particular, the docking mechanism developed over the years has played a key role in ensuring the success of the mission.
In the follow-up manned space missions, in addition to the manned spacecraft, cargo spacecraft, space laboratory and other tasks, Shanghai Aerospace also undertook the overall task of the experimental module II of the space station, the docking mechanism, power supply subsystem, non sealed module structure and general assembly, measurement and control communication equipment, optical module system energy function, docking subsystem function, measurement and control communication equipment and other research and development tasks.
In the electronic control system of "tianzhou-1", Zhongkexin (No. 58 Institute), located in Liyuan Development Zone, Binhu District, Wuxi City, contributed two core chips to control the motion of the spacecraft. No matter whether it is captured, buffered or pulled close, it can achieve the same precision.
According to the introduction of the engineers of Zhongkexin, the electronic control system of "tianzhou-1" is like the brain and nerve of the spacecraft, and these two chips are like "neural networks", sending out numerous branch data commands, connecting the data communication between various "organs" of the spacecraft, and controlling the spacecraft to complete various difficult actions. These two types of chips are not only used for "tianzhou-1", but also for "tiangong-2", "shenzhou-11" and some civil products, showing outstanding stability and reliability. Based on this, the R & D team applied for more than 20 patents.
Radiation resistance is a difficult problem in chip design. According to research and development personnel Cai Jieming, the radiation environment in high orbit space is very bad. If the chip can not resist radiation, it will send out wrong commands and data, which may cause the spacecraft to malfunction or run incorrectly. During the research and development period, Cai Jieming and his colleagues worked overtime for 20 or 30 hours a week. After two years of hard work, they finally made the radiation resistance data of the chip meet the design requirements. The radiation hardened chip is like a muscular "Boxer", which can withstand the impact of charged particles and protons from all directions and distances.
Many power supply products supporting the carrier system and spacecraft system of "tianzhou-1" are provided by China Electronics Technology 43 in Hefei, including six series 22 varieties of DC / DC converters and EMI filters used by Tianzhou spacecraft.
It is a series of products with the highest degree of serialization, the largest number of varieties and the most complete power coverage in China and even in the world. The technical indicators of the products have been identified as "international leading" level, which is of pioneering significance and improves the overall level of China's power supply bus system.
According to the relevant R & D personnel of CETC 43 Institute, in order to complete this mission, CETC 43 Institute has withstood two major tests. First, during the first official launch mission of Long March 7 carrier rocket, it developed and produced several special and highly reliable DC / DC converters and EMI filters to provide stable and reliable electric energy conversion for rocket precision control. Secondly, a series of aerospace grade DC / DC converters and EMI filters were developed and produced for the "tianzhou-1" spacecraft, which increased the bus voltage of the spacecraft by nearly four times, effectively improving the load capacity and total power supply efficiency of the spacecraft. These power products are the core components of the "tianzhou-1" spacecraft, just like the "heart" of the spacecraft.
The "Silk Road No. 1" scientific test satellite 01, which was launched with "Tianzhou No. 1", is the first earth observation micro nano satellite launched in China by means of cargo spacecraft. It carries the first aerospace grade high-speed image compression chip "Yaxin Tiantu" independently developed by China, and is jointly developed by the Institute of imaging of Xi'an University of Electronic Science and technology and 513 Institute of the Fifth Academy of Aerospace Science and technology. In addition, the Institute of imaging of Xi'an University of Electronic Science and technology has also undertaken the research and development of digital video coding and decoding equipment for remote operation cameras in the docking system of "Tiangong" and "tianzhou-1".
The scientific test satellite 01 has the characteristics of small size, light weight and high functional density. It carries a light and small visible light camera with a total weight of no more than 1kg, and the first aerospace grade high-speed image compression chip "Yaxin Tiantu" independently developed by China. It is jointly developed by the State Key Laboratory of Geographic Information Engineering in Shaanxi, Xi'an Aerospace skydrawing Data Technology Co., Ltd., Xi'an Institute of Optics and precision machinery of the Chinese Academy of Sciences, Xi'an University of Electronic Science and technology and other scientific research institutions. The retraction size of the whole satellite of "Silk Road 1" is only 330 mm × 100 mm × 100 mm, mass no more than 4.5 kg, designed orbital altitude of 400 km, with optical remote sensing earth observation capability, it is the first satellite of the "Silk Road microsatellite group earth observation system" and undertakes the task of system technical system verification.
The Silk Road micro satellite group plans to launch more than 30 micro and nano satellites, which can provide panchromatic, multispectral, hyperspectral and other types of remote sensing images and have enhanced navigation functions. Through networking, satellites can shorten the revisit period to one day, completely changing the old pattern of long revisit period and few product types of remote sensing satellites.
In addition, the "tianzhou-1" microwave radar signal processor and the "tiangong-2" microwave transponder signal processor, developed by Professor Wu siliang and Professor Cui Wei of the aerospace electronic technology research team of the school of information and electronics of Beijing University of technology, provide accurate relative position and motion parameter measurement information for "Tianzhou" and "Tiangong", and will guide "Tianzhou" and "Tiangong" to complete three "space kisses".
According to the introduction of Professor Wu siliang, the team leader, "tianzhou-1" microwave radar signal processor and "tiangong-2" microwave transponder signal processor belong to the second generation products of space rendezvous and docking microwave radar. Compared with the first generation products, the second generation products used in "tianzhou-1" and "tiangong-2" have new development. Professor Cui Wei said, "the product has added a two-way communication function to ensure the real-time information transmission between tianzhou-1 and tiangong-2 during the docking mission. At the same time, through design optimization, the second generation products are smaller in size, lighter in weight and lower in power consumption ".
Tianzhou-1 is a cargo ship, but its function is not limited to cargo transportation. In addition to completing the rendezvous and docking and fueling the tiangong-2 space laboratory, the launch of tianzhou-1 also carried a large number of experimental equipment. During its space operation, a number of experiments will be conducted. This time, tianzhou-1 has carried a total of 40 sets of equipment, and 13 space experiments will be carried out, truly realizing the multi-purpose of one ship. The space experiments to be carried out on tianzhou-1 include on orbit verification of new components, space environment detection, mechanical environment measurement, and life science experiments. In the future, the space station to be built in China will be huge, and it will inevitably be impacted by space debris in the process of space operation.
The cargo ship is a tool for transporting goods between heaven and earth. It will replenish propellant, air and food for the future space station of China and replace equipment for maintenance of the space station. At the same time, it will also be used as the "garbage can" of the space station for recycling the wastes of the space station. After leaving the space station, the cargo spacecraft burned down in the atmosphere together with the waste. Cargo system is the key technology that China needs to break through and master to build the space station, and is the basic premise to ensure the long-term manned flight of China's space station in the future.
The first of the three rendezvous and docking: unlike last year's tiangong-2 initiative to adjust its orbit and attitude to meet the rendezvous and docking of shenzhou-11 manned spacecraft, this time, in order to meet the needs of the future space station, tianzhou-1 needs to adjust its orbit to the position of tiangong-2. The second time: tiangong-2 turned 180 degrees, and tianzhou-1 circled from below to the front of tiangong-2 for the second rendezvous and docking through full autonomous flight. The third time: the rendezvous and docking between the two spacecraft will be completed within 6.5 hours.