Automated Subsystems Control Development

This paper describes the objectives, plans, and status of the NASA-sponsored program “Automated Subsystems Control for Life Support Systems (ASCLSS).” The program objectives are to define a generic automation approach for Space Station subsystems and to demonstrate the selected automation technique by controlling and monitoring the Air Revitalization Group (ARG) of a regenerative Environmental Control and Life Support system (ECLSS). The ARG consists of three ECLSS processes: CO₂ concentrator, CO₂ reduction, and O₂ generation.

The ASCLSS automation approach consists of a hierarchy of distributed controllers implemented with 1750A microprocessors and a high speed busing network. System level, process control, and real-time operating system software will be integrated with controller hardware to demonstrate the automated control and monitoring of three ECLSS processes. The ECLSS processes will be simulated by three ARG simulators, implemented in individual personal computers. A crew man-machine interface (MMI) will be included in the automation system to develop and demonstrate the control authority allocated between the crew, the upper level system controller, and the integrated ARG process controllers.