On-orbit Testing of the Advanced Closed Loop System ACLS
"The Advanced Closed-Loop System ACLS is a regenerative life support system for closed habitats. With regenerative processes the ACLS covers the life support functions of CO2 removal, Oxygen generation and CO2 Reprocessing. The ACLS Flight Model (FM) was launched to the ISS with HTV7 in September 2018 and was installed in the Destiny Module. In-Orbit Commissioning has been finalised for CO2 removal, oxygen generation and parallel CO2/O2 operation demonstrating good performance even at low CO2 levels. Further commissioning is still in process and is expected to be finalised later in 2020. During commissioning tests several unexpected problems had to be overcome mainly related to interfaces. ACLS is operated via a Ground Segment (GS) infrastructure installed at Airbus in Friedrichshafen, Germany, where also the ACLS Engineering Model is maintained and operated as ground reference model. The paper reports on the in-orbit installation, commissioning and troubleshooting of ACLS."