Did any fuel change direction after the spacecraft was separated from the rocket?

□ Morning News correspondent photo report in Beijing

Hu Jun 1986 graduated from Tsinghua University majoring in automation, and was admitted to 502 Aerospace Group in the same year. 1989 graduated and admitted to Peking University one year later. He is a graduate student in the field of control. 1993, he has been engaged in the guidance, navigation and design control of 502 manned spacecraft, serving as the chief designer of scheme design and the deputy chief designer of guidance, navigation and control. In February 2004, it became a manned spacecraft.

Release time

According to the integer days of returning the main landing site.

Reporter: Two pairs of things like wings on the spaceship are called windsurfing. Their function is to collect solar energy and provide electric energy for spacecraft. So are the windsurfing of the spacecraft fixed or moving?

Hu Jun: Take the initiative. Running on the orbital plane, the direction of the sun relative to the spacecraft is always changing. In this process, through the control algorithm of the sailboard and the capture and tracking means of the sensor, the sailboard is accurately aimed at the sun to ensure the maximum power generation energy. The normal flight of spacecraft in orbit is mainly provided by windsurfing, which stores some electric energy in the sunlight area and charges its battery through some internal circuits. In the shadow area, when there is no sun, the battery has to release electric energy to all parts to work.

Windsurfing is very important for spacecraft. If the windsurfing doesn't open, the spaceship must return urgently.

Reporter: How to determine the return time of the spacecraft?

Hu Jun: Usually, the return time is returned to the main landing site in integer days, and returned in integer fields of one day, two days, three days, four days and five days. If the emission time is fixed, so is the reflection time.

Now the orbit is a circular orbit, which will not change basically, and the small adjustment changes little. The number of return laps is very fixed, and the number of return days can be basically determined.

Reporter: during the return, is the spacecraft controlled by the ground or all by itself?

Hu Jun: The ground gives instructions to it and controls it by itself. All instructions have been loaded into the spacecraft before launch. If everything is all right, it will automatically go down according to its own program. During its return, all its tracks, including its position and speed.

black box

Sooner or later, I will return to earth.

Reporter: What about the black box on the spaceship?

Hu Jun: Black boxes are mainly flight speed recorders, especially in some places. For example, in the whole launch process, the calculation in the return process will be very intensive, and the records of some key sections of the whole on-orbit operation section will be very intensive. Black box is also an important data source to summarize the return of spacecraft.

Reporter: Will the black box on the spaceship come back?

Hu Jun: That's impossible, because it's near-Earth orbit. If you can't come back for a while, you can't come back for a day or two, you can't come back for a month or two, but because of low-earth orbit, you will return to Earth sooner or later.

land

The blockade is still under control.

Reporter: If there is something wrong with the spacecraft, will the astronauts be able to repair it? How can astronauts escape if there is something wrong with the spaceship?

Hu Jun: Generally speaking, there is no need for astronauts to be spaceships, and the system is more comprehensive. We can authorize an astronaut in a major emergency that concerns his life safety. He can enter the return capsule on his own, and his escape is nothing more than returning to earth as soon as possible. We have arranged an area for him to return to earth in each circle, and he can return to the program autonomously. The spacecraft system will work according to the autonomous return procedure and return to a safe place on the earth to wait for rescue.

Reporter: Is it possible to land in other countries or at sea when you return?

Hu Jun: It won't take long for the trajectory of Shenzhou VI to pass through China. It's certain to give priority to China, but if you are running laps and don't pass through China, you can only choose foreign landing sites.

Reporter: How is the spacecraft controlled in the black barrier?

Hu Jun: The spacecraft has an automatic control system and inertial navigation inside. Inertial navigation does not depend on external information, and its position, speed and attitude can be known through its own internal measurement and calculation. According to the position, velocity and attitude, the spacecraft can calculate the ratio of a specific point in a simulated orbit to the standard, and then control the engine to meet the requirements of guidance ability. The results of computer calculation will give the engine precise instructions to control the direction of the spacecraft, which means that the spacecraft can still control the lift in the raging fire during the return process.