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Complexity Evaluation of an Environmental Control and Life-Support System Based on Directed and Undirected Structural
Kaichun Yang1, Chunxin Yang1, Han Yang1
1School of Aeronautical Science and Engineering, Beihang University, Beijing 100191, China.
Entropy (Basel, Switzerland)
|September 28, 2021
Summary
Environmental control and life-support systems (ECLSS) are crucial for astronauts. This study evaluates ECLSS complexity using structural entropy, finding system structure changes have minimal impact on overall complexity for future spaceflights.
Area of Science:
- Space exploration engineering
- Systems engineering
- Life support systems
Background:
- Manned space missions require sophisticated Environmental Control and Life-Support Systems (ECLSS) to sustain astronaut life.
- ECLSS are complex hierarchical systems comprising subsystems, components, and individual machines.
- System-level conceptual design and performance evaluation are critical for effective ECLSS development.
Purpose of the Study:
- To present a top-level scheme for ECLSS, focusing on atmosphere revitalization, water, and waste management subsystems.
- To propose two ECLSS design schemes prioritizing enhanced closure and reduced power consumption.
- To quantitatively evaluate ECLSS complexity using the structural entropy method (SEM).
Main Methods:
- Utilized the structural entropy method (SEM) to calculate the system order degree for top-level ECLSS complexity assessment.
- Applied both directed and undirected SEM to analyze system complexity and identify differing evaluation rules.
- Investigated the impact of technological substitutions on overall system complexity.
Main Results:
- The structural entropy method (SEM) was employed to quantitatively assess the complexity of the top-level ECLSS design.
- Directed and undirected SEM analyses revealed distinct patterns in system complexity evaluation.
- Results indicate that modifications to individual technologies within the ECLSS structure do not significantly alter overall system complexity.
Conclusions:
- The proposed top-level ECLSS scheme and complexity evaluation provide valuable insights for future space mission life support.
- Understanding ECLSS complexity through SEM supports informed design decisions and technological integration.
- This research offers technical guidance for developing more robust and efficient life-support systems for long-duration manned spaceflights.
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