Astronauts install expansion pump set to complete extravehicular rescue verification
Similar to the first mission of Shenzhou XIV, one of the major tasks of this mission is to install the load expansion pump set. But unlike the last thermal expansion pump set, this expansion pump set mainly serves the extravehicular load.
Su Nan, the overall chief designer of the extravehicular mission machinery of the Space Station of the Fifth Academy of Aerospace Science and Technology Group: There are many experimental load devices outside the cabin, which will generate heat, so some coolant circuits are needed to take away the heat. The pump set is installed on the fluid circuit. The last installation was used for the platform equipment of the space station, and this installation circuit is specially used for the experimental load outside the cabin.
In addition to installing the expansion pump set, the most important thing for astronauts is to complete the first extravehicular rescue verification of the space station.
Su Nan, overall chief designer of the extravehicular mission machinery of the Space Station of the Fifth Academy of Aerospace Science and Technology Group: We designated an armrest as a simulated rescue position in the working cabin, and then two astronauts climbed over, one of them lost his working ability, and the other astronaut transported him back to the cabin. This is mainly a security issue. We can ensure that the astronauts are safely transferred back to the airlock.
How to determine the time for astronauts to leave the cabin?
The first time the Shenzhou XIV astronaut left the cabin was at 6: 00 p.m. in September of 1 year, and the second time was at 1 point in the afternoon of1year. What factors should be considered when choosing the opportunity to leave the cabin?
Wang: Deputy Chief Engineer of Beijing Aerospace TT&C Center: We made an optimization and improvement. In the past, the radiation impact of the Atlantic radiation belt on astronauts' extravehicular activities was mainly considered, so this optimization improved the evaluation method. In the past, it was to calculate the interval time directly passing through the radiation zone. This time, the cumulative amount of radiation received throughout the day was used as a reference for evaluation.
The adjusted exit window also fully considers the rest habits of astronauts and ground teams. After the extravehicular activity, astronauts can get a full rest without staying up late. In addition, the choice of this time window should also consider the space safety and communication safety during the astronauts' extravehicular activities.
Wang, deputy chief engineer of Beijing Aerospace Control Center: collision warning of space debris should be considered, and collision warning cannot be generated, which will affect the safety of the assembly. Second, we should consider the influence of the weather. If there is bad weather such as heavy rainfall, the relay measurement and control resources are unavailable, which leads to the failure to provide heaven and earth measurement and control links and image and voice transmission normally.
In order to successfully complete the construction task of this year's space station, the date of the second extravehicular activity of Shenzhou 14 is basically determined before the first extravehicular activity. With the expansion of the application scope of the space station, the time arrangement of astronauts' extravehicular activities will be more flexible.
Wang Chunhui, deputy chief designer of the astronaut system of China Astronaut Center: A crew has to perform several missions of extravehicular activities, mainly according to the requirements of the mission, and then there will be installation tasks, because new loads or new equipment require astronauts to leave the cabin to complete the installation of extravehicular products. With the extension of the operation time of the space station, some equipment needs regular maintenance by astronauts and also needs to leave the cabin. According to the planning of the whole space station, we will make arrangements then.