One of those pieces of cargo is a new 'robot hotel' that will provide a protected parking space for mission-critical robots at the ISS when they're not in use.
Its first residents will be two robots created to detect leaks from the station, which are capable of "sniffing" out the presence of gases such as ammonia. The robots use mass spectrometers to "sniff out" gases like ammonia leaking out from the space station.
Two RELL units are on board the station right now: the first RELL launched in 2015, and a second RELL was launched as a backup earlier this year.
RELL units take an extended amount of time to be deployed. The robots have been previously used and stored inside the ISS, but since space inside the ship is the most optimal spot for storing, its better for work-flow and ease of storing to have them outside the station. Once outside the station, those detectors now need to wait 12 hours in space to clear itself of water vapor and other gases from inside the station. This way, the deployment will only depend on the availability of Dextre, which can then easily locate the tool.
NASA plans on employing RiTS and RELL systems on the Lunar Gateway and human habitats on other planets.
Scheduled to lift off at 12:51 p.m. from Cape Canaveral Air Force Station Launch Complex 40, SpaceX is sending its Falcon 9 rocket to the International Space Station with science experiments, crew supplies and hardware onboard as part of NASA's Commercial Resupply Services program.