Life Support Goals Including High Closure and Low Mass Should Be Reconsidered Using Systems Analysis

Date

2017-07-16

Journal Title

Journal ISSN

Volume Title

Publisher

47th International Conference on Environmental Systems

Abstract

Recycling space life support systems have been built and tested since the 1960’s and have operated on the International Space Station (ISS) since the mid 2000’s. The development of space life support has been guided by a general consensus focused on two important related goals, increasing system closure and reducing launch mass. High closure is achieved by recycling crew waste products such as carbon dioxide and condensed humidity. Recycling directly reduces the mass of oxygen and water for the crew that must be launched from Earth. The launch mass of life support can be further reduced by developing recycling systems with lower hardware mass and reduced power. The life support consensus has also favored using biological systems. The goal of increasing closure using biological systems suggests that food should be grown in space and that biological processors be used for air, water, and waste recycling. The goal of reducing launch mass led to use of Equivalent System Mass (ESM) in life support advocacy and technology selection. The recent consensus assumes that the recycling systems architecture developed in the 1960’s and implemented on ISS will be used on all future long missions. NASA and other project organizations use the standard systems engineering process to guide hardware development. The systems process was used to develop ISS life support, but it has been less emphasized in planning future systems for the moon and Mars. Since such missions are far in the future, there has been less immediate need for systems engineering analysis to consider trade-offs, reliability, and Life Cycle Cost (LCC). Preliminary systems analysis suggests that the life support consensus concepts should be revised to reflect systems engineering requirements.

Description

Harry Jones, NASA Ames Research Center (ARC), USA
ICES501: Life Support Systems Engineering and Analysis
The 47th International Conference on Environmental Systems was held in South Carolina, USA on 16 July 2017 through 20 July 2017

Keywords

life support goals, closure, launch mass, systems analysis

Citation