<p>Although decades of experience in human spaceflight have produced and refined a wealth of operational knowledge, the unique challenges posed to long-term extraterrestrial surface habitats will require new approaches to mission design. The key objectives of this thesis are to develop an understanding of 1) how to use simulation to study these habitats and 2) how to make contingency plans for these habitats under complex, changing conditions. In order to accurately represent the challenges posed, we identify the common qualities of mission architectures that are likely to be present in near-future habitats. These qualities are used to formulate sample crew schedules that contribute to developing realistic models for meaningful research. We discuss the development of such models and demonstrate the suitability of simulation to enable the design and study of resilient space habitats. Simulation can be used as a tool to understand the challenges and consequences associated with decision making, as well as the importance of resilient design choices in a hazard-prone environment. We then identify aspects of vulnerability in space habitat mission operations, the subfactors that influence changes in habitat vulnerability, and the effects of each identified category of vulnerability. These ‘vulnerability factors’ are subsystem availability, environmental conditions, safety control options, and recent events. Each vulnerability factor has several subfactors that influence its change during a mission.</p> <p><br></p> <p>The set of vulnerability factors is significant because each captures some category of behavior in surface habitats that changes over time and impacts the likelihood or consequences of risks to the habitat. We use these vulnerability factors to formulate six research questions which can be addressed via simulation-based research. A simulation set plan is developed to highlight the significant concepts at play in each research question. Finally, we conduct trials and analyses of these questions via simulation by injecting faults into a modular coupled virtual testbed for space habitats. The results of the simulations are used to develop lists of key implications for each vulnerability factor in practice. In addition, the lessons learned over the course of simulation set design and the usage of the simulation tool are discussed to support future simulation-based research efforts. We conclude by summarizing the major findings and potential for future work in the area.</p>

<p>  </p> <p>In the wake of the first Artemis launch, humanity is more focused on space exploration and travel than it has been in the half a century since the Space Race. This time, it’s not enough just to touch down on the Moon; we want to build sustainable homes on the Moon and on Mars. The goal of long-term extra-terrestrial habitation begs the question: how do we design habitats that can protect human life so far from Earth?</p> <p><br></p> <p>The Resilient Extra-Terrestrial Habitat Institute (RETHi) has been operating for four years now building a foundation of ideologies and tools to help answer that question. The institute has developed a control-theoretic approach to habitat resilience based on a state-trigger analysis, a database of potential hazards to a habitat, metrics for resilience quantification, and simulation platforms for design verification.</p> <p><br></p> <p>The combination of these developments allows for the proposition of a resilience-oriented habitat design process. The process takes the shape of a typical systems vee and is tailored to the needs of an extra-terrestrial habitat and the tools available through RETHi. The process proposes a way to build resilience into the requirements development and design verification of extra-terrestrial habitats at three system levels. The result of this study is a discussion on how we design, evaluate, and select safety mechanisms for extra-terrestrial habitats.</p> <p><br></p> <p>Safety mechanisms are selected by simulating the habitat’s response to a disruption when equipped with one safety mechanism at a time and quantifying the habitat’s resilience. Then, the resilience of the habitats with different mechanisms are compared, illuminating the best option. Simulations for each mechanism are performed under a variety of circumstances, changing the time of day and intensity of the disruption as well as the type of repair agent carrying out the mechanism to capture the habitat’s behavior as totally as possible.</p> <p><br></p> <p>This analysis shows how different safety mechanisms performances compare and provides a basis for making design decisions.</p>