A Habitability Index for Assessing and Monitoring ECLSS Robustness, v1.0



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2024 International Conference on Environmnetal Systems


Human exploration of deep space will require Environmental Control and Life Support Systems (ECLSS) of greater robustness as mission duration and distance from Earth increase. As crews travel to distant unexplored environments, designers need heightened confidence in life support availability under increasing levels of uncertainty and risk. This paper is the third in a series addressing the topic of robust ECLSS design. The first paper defined ECLSS robustness and discussed distinctions between robustness, reliability, resilience, and survivability. The second paper reviewed several potential methods for quantifying robustness and proposed an ECLSS robustness metric for use in design evaluation and improvement. In this third paper, we specifically define the key performance characteristic of ECLSS, the habitability index, as a utility function of all contributing environmental factors controlled by the ECLSS. Marginal utility functions for CO2 concentration, O2 concentration, food quality, water quality, etc. are defined based on published exposure limits or other recommended values for a healthy human crew. This paper provides functions and baseline values for habitability index calculating durin ECLSS design or real time habitat health monitoring.


Christine Escobar, Space Lab Technologies, LLC, USA
James Nabity, University of Colorado Boulder, USA
ICES506: Human Exploration Beyond Low Earth Orbit: Missions and Technologies
The 53rd International Conference on Environmental Systems was held in Louisville, Kentucky, USA, on 21 July 2024 through 25 July 2024.


habitability, robustness, ECLSS, utility function