Resilience evaluation of the environmental control and life support system of a spacecraft for deep space travel

Abstract

In deep space manned travels, the crew life will be totally dependent on the environment control and life support system of the spacecraft. A life-support system for manned missions is a set of technologies to regenerate the basic life-support elements, such as oxygen and water, which makes resilience a paramount feature of this system. The resilience of a complex engineered system is the ability of the system to withstand failures, continue operating and recover from those failures with minimum disruption. Resilient design is a new design framework on which the main goal is to quantify system resilience upfront in order to guide the design team during the conceptual design stage. In this article, we present a tool that combines a rule-based approach with a Monte Carlo-based approach to evaluate the resilience of a proposed environment control and life support system designed for deep space travel. Based on the results found, we explore a few design alternatives in order to increase system resilience.

Terraform Sustainability Assessment Framework for Bioregenerative Life Support Systems

“…The noted challenges in quantifying a measure of resilience are that 1) one must identify the multitude of disruption scenarios specific to the design of the system in question and necessarily apply a probabilistic scoring system to a limited set of classes of disruptions, and 2) given the inherent limited life of engineered systems, resilience will degrade over time, thus further constraining the time frame of scoring (Haimes 2009). The two challenges have been addressed specifically for ECLSSs using a Generalized Resilient Design Framework (GRDF) that limits disturbances to the failure of parts within the system; approximates all part failures to happen with equal, low probabilities; and considers such resilience only within a maximum, useful lifetime period during which the probability of any given part failing does not change (Matelli and Goebel 2018). The generalized resilient design framework for quantifying resilience can be applied to any ECLSS.…”

“…It is noteworthy to consider the assumption that BLSS is inherently more sustainable than ECLSS due to the presence of bioregenerative components. For any given functional objective and the best available ECLSS and BLSS technologies that can be selected to meet the objective, sustainability will be affected by the engineered resilience of the non-regenerative parts of the system (Haimes 2009;Matelli and Goebel 2018) and the particular supply chains needed for the given technology to provision maintenance materials, repair parts, and consumable materials. The expectation is that sustainability is heavily weighted by both ECLSS/BLSS design and supply chain performance under load, and the risk mitigations, and adaptive management plans prepared for the common and unique disturbance points.…”