Chinese astronauts exited from Wentian experimental cabin airlock and successfully completed the set task
A picture of astronauts Chen Dong (top) and Liu Yang (bottom) carrying out extravehicular operations, taken at the Beijing Aerospace Flight Control Center.
Astronaut Chen Dong successfully opened the exit door of the Wentian experimental cabin airlock. Published by Xinhua News Agency (Photo by Li Jie)
The reporter learned from the Fifth Academy of China Aerospace Science and Technology Corporation that from the overall development of Tianzhou-4, Shenzhou-14, and Wentian experimental modules, the scientific and technological team of the Academy once again fully supported the success of the mission.
Larger doors for easier access
When the Shenzhou 12 and Shenzhou 13 crews exit the cabin, they pass through the exit hatch located in the node cabin of the core cabin of the space station, and the diameter of the cabin door is 85 cm. In this mission, the astronauts “go out” from the airlock cabin of the Wentian experimental cabin for the first time. The cabin door was developed by the structure and organization team of the Fifth Academy of Space Station. The diameter reaches 1 meter, allowing the astronauts to wear extravehicular spacesuits In the case of , the device can be carried through more calmly.
The seemingly simple increase in geometric size is actually a balance between “rigidity” and “softness”. It is necessary to use the principle of lever amplification to find a balance point. Under the condition that the astronaut’s operating force remains unchanged, a hatch with a larger diameter can be realized. seal.
As a complex product in the spacecraft mechanism, the 1-meter diameter hatch covers sealing, transmission, locking, guidance, lubrication, ergonomics and other disciplines, but the design team has implemented complex functions into the details of product operation in a simple way. The astronaut only needs to use the operating handle on the door body to rotate and unlock, use the power assist mechanism to eliminate residual pressure, and pull the handle of the door to complete the action of opening the door.
In addition, the cabin door is also equipped with a customized protective cover, and the cabin door leak detector is used as a sealing detection method, and the cabin door pressure point switch is used as a state auxiliary judgment to ensure its safety in all aspects.
According to the different needs of on-orbit use, the development team has also equipped a variety of hatch products with different functions in the follow-up missions such as the Mengtian experimental cabin.
Longer safety ropes, freer space walks
When astronauts perform the mission of exiting the capsule, they must be guarded by a “lifeline” connected to the space station at all times. This is the retractable safety tether mechanism developed by the 529 Factory of the Fifth Academy.
When Zhai Zhigang, an astronaut of Shenzhou 7, completed my country’s first space flight, he used a fixed-length tether with an effective length of just over 1 meter. However, in the construction of the space station, the astronauts have to complete the installation and maintenance of space station equipment and other tasks. The scope of the space station is larger, the operation is more difficult, and the safety requirements are stricter. A longer and retractable safety tether mechanism is required.
To this end, the research team has developed a new retractable safety tether mechanism suitable for space station evacuation tasks. This kind of safety rope can ensure a safe connection of more than 10 meters between the astronaut and the space station cabin, without hooking the space suit and interfering with the movement of the astronaut. Photo, space particles and other harsh environment tests. At the same time, taking into account the requirements of ergonomics, the product should also achieve constant force output to ensure that its retractable force does not affect the astronaut movement.
In response to the design requirements of long distance and adaptability to the space environment, the R&D team innovatively proposed an ingenious design scheme, which realizes the constant force retraction of the wire rope without the need for a motor to provide rotational torque, avoids the introduction of cables, and ensures that the astronauts can carry convenience and mobility.
At the same time, the designers choose special covering materials resistant to space radiation to protect the steel wire rope to ensure the safety of the mechanism. In order to meet the requirements of long-life use, they adopted the design scheme of the auxiliary rope pulley set to guide the wire rope row, and through a large number of tests and verifications, it was ensured that the 10-meter-long wire rope could be repeatedly and orderly wound tens of thousands of times in a narrow mechanism.
More lights, pilotage beacon for astronauts
In this mission, the astronauts can carry out extravehicular operations in a clearer and brighter environment, thanks to the two new “artifacts” brought by the instrumentation and lighting subsystem to the astronauts: the pan-tilt lighting.
The space station has planned an integrated, multi-level and multi-dimensional lighting system with multiple cabin segments and multiple degrees of freedom dynamic lighting as the main and fixed lighting as the supplement. The extravehicular pan/tilt lighting launched by the Suiwentian experimental module has the function of full coverage angle rotation. Through the multi-degree-of-freedom rotation mechanism and the design of the projection light optical system, the astronaut exit path and the illumination of the extravehicular operating point are fully guaranteed. , and become a “pilot beacon” for astronauts to walk outside the cabin.
In fact, in addition to exiting the cabin, the care of the astronauts by the instrument lighting subsystem is also reflected in every moment of space life.
Unlike the earth, space does not have the changes of day, night and seasons. Astronauts experience about 14 sunrises and sunsets every day in orbit, and the body’s biological clock is easily disrupted, which may cause sleep disorders, burnout, health damage and work efficiency to a certain extent.
Through this system, after astronauts enter the space station, they can pass through according to their personal needs.cell phoneThe app adjusts the lighting environment in the cabin and switches between sleep, work, exercise and other modes to avoid discomfort caused by a long-term monotonous environment and ensure efficient work and high-quality sleep.