EXPRESS Racks

Astronaut James D. Halsell, Jr., mission commander, checks on an experiment in the Astro-Planet Generic Bioprocessing Apparatus onboard the Earth-orbiting Space Shuttle Columbia, 2017. The Microgravity Sciences Laboratory (MSL-1) had just completed the first one-third of its manifest time frame. The image was recorded with an Electronic Still Camera (ESC) and later downlinked to ground controllers in Houston, Texas.

Credits: NASA

Joel Hardy, Vincent Vidaurri, and Nancy Hallmark in the Mission Operations Laboratory, Laboratory Training Complex (LTC), MSFC building 4663, undergoing EXPRESS Rack training, 2014.

Credits: NASA

EXpedite the PRocessing of Experiments to the Space Station (EXPRESS) Racks are multipurpose payload rack systems that support and store research experiments aboard the International Space Station (ISS). The EXPRESS Racks enable simple integration of multiple payloads with standard interfaces that can accommodate up to ten small payloads, resulting in a total operation capability of eighty experiments. The EXPRESS Rack facilities are comprised of several subsystems that enable operations: Rack Interface Controller (RIC), EXPRESS Memory Unit (EMU), Payload Ethernet Hub/Bridge (PEHB), EXPRESS Laptop Computer (ELC), EXPRESS Rack Thermal System, and the Solid State Power Controller Module (SSPCM). These Racks are integral to securing and operating equipment and experiments in the Space Station’s low gravity, or microgravity, environment.

The EXPRESS Racks can support science experiments of any discipline and provide stowage, power, data, command and control, video, water cooling, air cooling, vacuum exhaust, and nitrogen supplies to the payloads. Payloads within the Racks can operate independently of one another. Each research facility is housed in an International Standard Payload Rack (ISPR), a container that serves as the facility’s exterior shell. Facility experiments can be directly controlled by the ISS crew or remotely controlled by the Payload Rack Officer (PRO) at the Payloads Operations Integration Center (POIC) at Marshall Space Flight Center.

The first EXPRESS Rack was successfully tested in 1997 during the STS-94 mission with a focus to evaluate Microgravity Science Laboratory-1 payload facilities. Two EXPRESS Rack experiments on this mission were activated fourteen hours into flight and operated until the fifteenth day of the mission, proving the system’s ability to support payload operations. EXPRESS Racks 1 and 2 launched to the ISS on STS-100 in April 2001; Racks 4 and 5 on STS-105 in August 2001; Rack 3 on STS-111 in June 2002; Rack 6 on STS-126 in November 2008; Rack 7 on STS-131 in April 2010; and Rack 8 on STS-133 in February 2011.

Resources

https://www.nasa.gov/mission_pages/station/research/experiments/608.html

https://www.nasa.gov/centers/marshall/news/background/facts/expressrack.html

https://www.nasa.gov/centers/marshall/news/background/facts/expressracks3.html

https://www.nasa.gov/centers/marshall/news/background/facts/express4_5.html