The first laboratory module will provide additional navigation avionics, propulsion and [[Yaw, pitch and roll#Aircraft attitudes|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 wind]]s.
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 then moves Wnetian to Starboard-side and upcoming Mengtian module to a portside port of the CCM.<ref>{{cite news |url=https://www.nasaspaceflight.com/2021/04/china-station-construction-begins/ |title=China readies launch of Tianhe module, start of ambitious two-year station construction effort |first1=William |last1=Graham |first2=Chris |last2=Gebhardt |date=April 28, 2021 |website=NASASpaceflight.com |quote=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.}}</ref> 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.<ref>{{Cite book |last=Hong Yang |title=Manned Spacecraft Technologies |publisher=Springer |year=2020 |isbn=978-9811548970 |___location=China |pages=355}}</ref><ref>{{cite news |url=https://www.nasaspaceflight.com/2021/04/china-station-construction-begins/ |title=China readies launch of Tianhe module, start of ambitious two-year station construction effort |first1=William |last1=Graham |first2=Chris |last2=Gebhardt |date=April 28, 2021 |website=NASASpaceflight.com}}</ref>
Wentian was successfully relocated to the starboard port on 30 September 2022 at 04:44 UTC<ref>{{cite web|title=我国成功实施问天实验舱转位|url=https://news.sciencenet.cn/htmlnews/2022/9/487156.shtm#:~:text=%E5%8C%97%E4%BA%AC%E6%97%B6%E9%97%B42022%E5%B9%B49,%E8%88%B1%E6%AE%B5%E8%BD%AC%E4%BD%8D%E6%93%8D%E4%BD%9C%E3%80%82|publisher=科学新闻网|access-date=30 September 2022}}</ref> by indexing robot arm.
