Today is space with you [No. 1362]
On the morning of January 8, the Shenzhou 13 astronaut crew, in close coordination with the ground scientific and technological personnel, adopted a hand-controlled remote operation method in the core module of the space station, and successfully completed the rendezvous and docking test of the Tianzhou-2 cargo spacecraft and the space station combination. This is the first time that Chinese astronauts have conducted a hand-controlled remote operation test in orbit. What is manual remote operation? What are the difficulties and characteristics compared with the previous manned spacecraft hand-controlled rendezvous and docking? What is the difference between domestic and foreign technology applications?
What is manual remote operation?
Manual remote operation is a remote operation by the astronaut using manual technology in orbit to remotely control the spacecraft, control the cargo spacecraft and the space station for rendezvous and docking, is specially equipped for the unmanned aircraft equipped with the function, and the Shenzhou manned spacecraft hand-controlled rendezvous and docking similar.
In the core module of the space station, the astronauts "piloted" the cargo spacecraft to dock with the space station by remote means. Throughout the process, the astronaut's perspective is "looking" from the spacecraft to the space station, as if sitting in a cargo spacecraft. The instrument system, operation handle, etc. faced by the astronauts are similar to the two hand-controlled rendezvous and docking implemented on the Shenzhou spacecraft before, which minimizes the training difficulty of the astronauts and reduces the burden of operation and recognition.
Development of rendezvous and docking technology
With the in-depth development of space exploration by mankind, spacecraft rendezvous and docking technology is one of the key parts of the development of space technology, and is an important symbol of the country's comprehensive national strength and aerospace science and technology. Since the United States successfully realized space rendezvous and docking for the first time in 1966, space docking and separation technology, as an important development direction of space technology, has developed rapidly.
So far, including the United States, Russia, the European Space Agency, Japan and China are vigorously studying spacecraft rendezvous and docking and separation technologies, and have completed hundreds of rendezvous and docking and separation missions. For example, the United States used the rendezvous and docking of the lunar module and the Apollo spacecraft in its lunar landing flight, and the Soviet Union used the rendezvous and docking of the Soyuz spacecraft and the Mir space station.
Spacecraft rendezvous, docking and separation technology has been recognized as one of the important technologies in the field of spaceflight, and successful rendezvous and docking and effective separation are essential for many space missions, such as space station replenishment, astronaut rotation, etc.
How do I perform manual remote operation?
Taking this test as an example, the Shenzhou 13 astronaut crew issued a control command in the core module, allowing Tianzhou-2 to separate from the core module first, and then the astronauts manually controlled the position and attitude of the entire cargo spacecraft, withdrew to a certain distance in the forward direction, and then controlled it again for docking until the locking was completed.
What are the difficulties/features compared to before?
Compared with the hand-controlled rendezvous and docking of manned spacecraft, the manual remote operation of cargo spacecraft has its own difficulties and characteristics. In terms of the speed of response of operations and the agility of movement, the difference between a manned spacecraft and a cargo spacecraft is like driving a car and a truck. There are two reasons for this: first, the hand-controlled remote operation of the cargo spacecraft needs to transmit the image "seen" by the camera on the cargo spacecraft to the space station, and the astronauts on the space station need to transmit the instructions back to the cargo spacecraft, which causes the delay in the astronaut's reaction and execution of the instructions; the second is that the cargo spacecraft is heavier than the manned spacecraft, and the translation acceleration is small, so the action is not agile.
What is the significance of the construction of the space station?
Remote operation rendezvous and docking tests are very important for the construction of the space station, and the manned spacecraft can complete the docking with the space station through the astronaut piloting the spacecraft and manual operation. Cargo spacecraft is different, once the automatic rendezvous and docking function fails, the cargo spacecraft will not be able to dock with the space station, resulting in mission failure, so the cargo spacecraft must have the function of remote control operation, and the automatic rendezvous and docking technology is mutually backup. This test preliminarily verified the function and performance of the manual remote operating system of the space station and the visiting aircraft, as well as the rationality of the cooperative working procedure between heaven and earth.
Domestic and foreign technology applications
China: self-control is the mainstay, supplemented by hand control
In the early stage of exploration and practice, China has carried out many space rendezvous and docking experiments, solved the problem of space rendezvous and docking, and mastered the fully automatic control technology of rendezvous and docking and the manual control technology of spacecraft astronauts. Shenzhou 9 astronaut Liu Wang played a beautiful "ten rings" in space, which proves that China's astronauts have a superb and world-class manual operation level and excellent psychological quality. In the routine flights since then, rendezvous and docking have adopted the method of self-control as the main and manual control as the supplement to reduce the load of astronauts. In the event of an automatic control failure, or in the event of an emergency (such as the risk of an orbital debris collision), the astronaut will manually intervene to execute the flight command.
International: Combination of manual and automatic control
The most basic principle of docking mechanism design is to ensure that the mechanism has the required functions at the same time, but also have high reliability and as little weight as possible, so the international general application of long distance automatic and close to the use of manual and automatic combination of the program, so that both safer and reliable can ensure sufficient accuracy, and achieve soft docking. When the automatic control flight range of the final approximation stage is not easy to grasp, the use of manual control can improve the success rate of the mission.
The future development of rendezvous and docking technology
On the basis of breaking through and mastering related technologies such as long-term manned presence in low Earth orbit and participation in near-Earth space applications, manned deep space exploration activities such as manned moon landing, manned asteroid exploration, and manned Mars exploration have become an important international development direction, and rendezvous and docking technology is an important means to realize future manned deep space exploration missions. Rendezvous and docking technologies need to be further developed, including effective and economical rendezvous and docking system strategies, trade-offs using autonomous and manned control methods, the development of advanced sensor technology and the development of rendezvous and docking mechanisms to meet the needs of future tasks.