Scaled Automated Pressure Regulation System for Analog Moon and Mars Habitat

Abstract

As humans look to travel off-world, sealed habitats will be essential for life support in long-duration missions. Previous closed ecosystem experiments have ranged from closed-loop habitats sustaining a single individual (NASA�s Biohome) to large scale self-contained systems designed to support a full crew (Biosphere 2, Lunar Palace 1).

To date, human-in-the-loop, closed ecosystem studies have focused on either mechanical life support or bio regeneration for extended space missions. The Space Analog for the Moon and Mars (SAM) at Biosphere 2 aims to meld these two approaches. SAM will consist of the historic Test Module greenhouse connected to a crew quarters and airlocks, surrounded by a simulated Mars yard.

Any sealed chamber must be prepared for potential interior cabin pressure loss and be able to compensate for changing external pressures where an external atmosphere exists, especially in the case of inflatables. The Test Module includes an existing analog pressure regulating system. The added crew quarters will require an independent pressure regulating system. A team of six engineering students at the University of Arizona is working with the executive team at SAM and Biosphere 2 to design and prototype the Automated Pressure Regulation System (APRS) for the SAM crew quarters. The goal of the system is to maintain a positive pressure in relation to the outside environment, preventing potential biocontaminants from entering. The APRS is a semi-closed system, drawing from an internal air source and external air resupply. To verify the APRS design, a 1:10 scaled model of the overall system and crew quarters are being constructed.

The APRS consists of four subsystems: a compressor system, scaled crew quarter module with a utility wall, sensor subassembly, and GUI subassembly. This paper will discuss the overall mechanical system, software design, and test validation procedures proposed for the APRS.