A molecular-sieve-based portable life support system (PLSS) for microgravity extravehicular activity (EVA) has been designed to minimize weight, volume, and expenditures of consumables for missions with numerous EVA's. The PLSS incorporates a regenerable two-bed molecular sieve system for CO2 and humidity removal, and a regenerable nonventing thermal sink for temperature control.
The molecular-sieve-based PLSS design is modular. This approach simplifies initial manufacturing tasks, facilitates subsequent maintenance tasks, and provides the potential to tailor the PLSS to the specific environmental parameters (metabolic load, radiative environment, duration) of a given EVA excursion.
This paper presents the molecular-sieve/regenerative nonventing thermal sink PLSS design and discusses the analyses and trade studies which support the design. The modular design and its benefits are discussed, and the reduced launch weight requirements of the regenerable system are quantified.