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International Space Station life support hardware is controlled mainly from the ground by executing standard operating procedures. While some on-board software exists for safety purposes, most commands are sent from ECLSS ground controllers to achieve mission objectives. This will prove unwieldy for extended operations with increasing time delays. This paper presents a new approach to encoding standard operating procedures that provides a path to greater autonomy in life support operations. Software tools will allow for adjustable automation of procedures from either the ground or on-board. The Cascade Distiller System (CDS) being tested at NASA Johnson Space Center is used as an example system.

This paper describes the re-engineering of the hardware and software organization of an autonomous control system for advanced water recovery technology development. The hardware changes from large standing racks of VERSAModuleEurocard (VME) computers and I/O cards to a set of small, modular controllers embedded in the hardware of the controlled systems. Additionally, the paper describes the redesign of an existing intelligent control architecture, known as 3T, that since 1995 has provided autonomous 24/7 controls to several long-duration life-support systems in ground tests at JSC. The software is recast from a vertical, message-passing architecture to a distributed system which can populate the embedded hardware controllers in many alternative arrangements. Additional controllers allow for automatically migrating control codes when the original controllers fail.

A Lunar habitat will require a level of automation that is much greater than previous human space missions. The complexity of the habitat, the distance (and time delay) between the habitat and ground controllers and the fact that the habitat may be uncrewed for periods of time all point towards increased automation of the habitat. NASA JSC is developing an integrated testbed for exploring operational concepts for a Lunar habitat that includes significant automation. The testbed allows for early investigation of the hardware and software design decisions and their impacts on operating a Lunar habitat. The testbed also allows for investigation into the robustness of different automation concepts with respect to failures and perturbations of the system. The testbed consists of both dynamic simulations of habitat systems and some physical hardware-in-the-loop.

In past papers we have described the design and development of a distributed version of 3T, the three-layered AI control system. In this paper we report on its efficacy in the control and management of a cascade distiller system (CDS) for wastewater recovery. In current lunar habitat design studies, distillation is the centerpiece of water recovery, and the CDS is one of the leading technologies being investigated to fill this role. With 3T, the CDS runs autonomously and continuously, but with the option of human intervention in parts or all of the system. We will describe the final hardware and software design, the major operating and recovery procedures and recount how 3T accommodated the specialized processing requirements of the year long CDS readiness test.