The objective of this research is to develop a mathematical model and control algorithm for the maintenance of the environmental system within the Controlled Environment Research Chamber (CERC) located at the National Aeronautics and Space Administration (NASA) Ames Research Center, Moffett Field, CA. The hypobaric research chamber is currently undergoing renovation as part of the Human Exploration Development Project (HEDP), an effort on behalf of NASA for advanced life support research. A broad overview of the chamber is provided which includes a physical description, preliminary system hardware and associated performance, and potential experimental uses. A mathematical model of the chamber air mass has been developed based on key energy and mass balances. Two methods of adaptive control have been implemented for the coupled control of temperature, oxygen concentration, pressure and humidity within the closed environment. Simulation testing algorithms performance have been conducted, including a step and modified ramp response. The results of the simulations indicate the adaptive methods performed well for the model presented. Further research is required in refining the chamber model for algorithm optimization and validation including the integrated of selected hardware dynamics.
http://archive.org/details/mathematicalmode00math
Lieutenant, United States Navy
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