Laboratory Cabin Module

Summary

The Laboratory Cabin Module (LCM) (Chinese: 实验舱) is a modular component of the Tiangong space station. Based on the Tiangong-2 experimental space module, the LCMs complete the third and final stage of Project 921, the CNSA's program to establish a permanent Chinese space station. While China's small unmanned spacecraft can provide platforms for zero gravity and exposure to space for scientific research, the LCMs offer a long term environment combined with ready access by human researchers over periods that far exceed the capabilities of Shenzhou spacecraft. Operations will be controlled from the Beijing Aerospace Command and Control Center in China.

Laboratory Cabin Module
Tiangong 2 space laboratory model.jpg
A model of Tiangong-2, the prototype for the LCMs
Module statistics
Launch date24 July 2022: Wentian
October 2022: Mengtian
Launch vehicleLong March 5B
Mass~21,500 kg (47,400 lb)
(dry mass of each LCM)
Length17.9 m (59 ft)
Diameter4.2 m (14 ft)

The first LCM Wentian (simplified Chinese: 问天; traditional Chinese: 問天; pinyin: Wèn Tiān; lit. 'Quest for the Heavens[1]') was launched into orbit on 24 July 2022. The second LCM Mengtian (simplified Chinese: 梦天; traditional Chinese: 夢天; pinyin: Mèng Tiān; lit. 'Dreaming of the Heavens[2]') is scheduled for launch in October 2022.[3]

PurposeEdit

 
Diagram of the Wentian module
 
Diagram of the Mengtian module

The first laboratory module will provide additional navigation avionics, propulsion and orientation control as backup functions for the Tianhe Core Module (TCM). Both LCMs provide a pressurized environment for researchers to conduct science experiments in freefall or zero gravity which could not be conducted on Earth for more than a few minutes. Experiments can also be placed on the outside of the modules, for exposure to the space environment, cosmic rays, vacuum, and solar winds.

The axial port of the LCMs will be fitted with rendezvous equipment and will first dock to the axial port of the CCM. A mechanical arm dubbed, as Indexing robotic arm, looking a sort of Lyappa arm used on the Mir space station moves Wentian to Starboard-side and upcoming Mengtian module to a portside port of the CCM.[4] It is different from Lyappa as it works on a different mechanism. Lyappa arm is needed to control the pitch of the spacecraft and redocking in a different plane. But the indexing robot arm is used when docking is needed in the same plane. In addition to this arm used for docking relocation, the Chinarm on Tianhe module can also be used as a backup in place of Indexing robot arm.[5][6]

 
Indexing Robot Arm on Wentian

Wentian was successfully relocated to the starboard port on 30 September 2022 at 04:44 UTC[7] by indexing robot arm.

In addition to this, both also house a small 5 m (16 ft) long robotic arm like the Chinarm as a supplemental to that arm. It is used for manipulating extravehicular payloads and their positioning accuracy is 5 times better than the Chinarm. There are standard adaptors (silver squares) on the modules to host the payloads.[8] There is also an adapter by which one of these arms can be grappled by the Chinarm it to work a single robotic arm like Orbiter Servicing Arm with Canadarms.[9]

Electrical power is provided by two steerable solar power arrays, which use photovoltaic cells to convert sunlight into electricity. Energy is stored to power the station when it passes into the Earth's shadow. Resupply ships will replenish fuel for LCM 1 for station-keeping, to counter the effects of atmospheric drag.

DimensionsEdit

The length of each module is 17.9 m. They are cylindrical with a maximum diameter of 4.2 m and an on-orbit mass of approximately 20,000 kg (44,000 lb) apiece.[10][11]

LaunchEdit

Both modules are due for launch in 2022 on Long March 5B launch vehicles from Wenchang Satellite Launch Center. Wentian is scheduled to launch on 24 July 2022, while Mengtian is scheduled to launch in October.[3] They will be inserted into a low Earth orbit with an average altitude of 393 km (244 mi) at an orbital inclination of 42 degrees, centered in the Earth's thermosphere.[10][12]

See alsoEdit

ReferencesEdit

  1. ^ "Planned space station details made public". China Daily. 2018-04-26. The two space labs, Wentian, or Quest for Heavens, and Mengtian, or Dreaming of Heavens
  2. ^ "Planned space station details made public". China Daily. 2018-04-26. The two space labs, Wentian, or Quest for Heavens, and Mengtian, or Dreaming of Heavens
  3. ^ a b Jones, Andrew (31 May 2022). "Rocket to launch China's next space station module arrives at launch center". SpaceNews. Retrieved 1 June 2022.
  4. ^ Graham, William; Gebhardt, Chris (April 28, 2021). "China readies launch of Tianhe module, start of ambitious two-year station construction effort". NASASpaceflight.com. This means the two future science modules, Wentian (“Quest for the heavens”) and Mengtian (“Dreaming of the heavens”), cannot dock directly to their planned radial port locations. [...] To account for this, each module will carry a Russian Lyappa robotic arm — like the ones used on Mir for the same purpose — to move the module from the forward port to its respective permanent location on a radial port of Tianhe's docking hub.
  5. ^ Hong Yang (2020). Manned Spacecraft Technologies. China: Springer. p. 355. ISBN 978-9811548970.
  6. ^ Graham, William; Gebhardt, Chris (April 28, 2021). "China readies launch of Tianhe module, start of ambitious two-year station construction effort". NASASpaceflight.com.
  7. ^ "我国成功实施问天实验舱转位". 科学新闻网. Retrieved 30 September 2022.
  8. ^ Twitter https://twitter.com/cnspaceflight/status/1550846854123778049. Retrieved 2022-07-23. {{cite web}}: Missing or empty |title= (help)
  9. ^ Twitter https://twitter.com/cnspaceflight/status/1543492387950931969. Retrieved 2022-07-23. {{cite web}}: Missing or empty |title= (help)
  10. ^ a b Barbosa, Rui C. (1 March 2021). "China preparing to build Tiangong station in 2021, complete by 2022". NASASpaceFlight.com. Retrieved 15 March 2021.
  11. ^ 王, 翔; 王, 为 (2021). "天宫空间站关键技术特点综述". 中国科学: 技术科学 (in Chinese). 51 (11). doi:10.1360/SST-2021-0304. Retrieved 2021-11-13.
  12. ^ David, Leonard (7 March 2011). "China Details Ambitious Space Station Goals". Space.com. Retrieved 23 February 2012.

External linksEdit

  • Chinese Space Agency website