Overview of the ISS Columbus module avionics

The European module Columbus of the International Space Station (ISS) includes a number of systems that makes it to a certain extent a stand-alone spacecraft, though all of them are interfaced with the ISS systems and exchange telemetry and data with the station and the ground segments. In particular, the Columbus includes a Command and Data Handling System (C&DHS) a Communication and Tracking System (C&TS), an Electrical Power System (EPS), an Environmental Control and Life Support System (ECLSS), a Thermal Control System (TCS). The only functions that are not carried out by Columbus systems are Attitude Determination and Control (ADC) and Guidance, Navigation and Control (GNC). The C&DHS in Columbus is called Data Management System (DMS) and the C&TS is simply called Communication System (COMMS). This paper describes in detail these two strictly astrionics systems on-board the Columbus. The DMS is one of the most important systems in Columbus module because it interfaces with every other system in the module as well as the ISS. As the “brain” of the module, the DMS monitors all aspects of its operations and distributes payload and systems data to the crew and to personnel on Earth via Tracking and Data Relay Satellites (TDRS). The architectures of the two systems and of their hardware interfaces are also presented. The DMS hardware includes data processors, control and monitoring processors, crew interface computers, data acquisition and distribution networks and interfaces to systems and payloads. The DMS architecture is structured in two layers: a vital layer and a nominal layer. Safety critical functions are carried out by the vital layer, which features a caution and warning system. An overview of software functions is finally presented.