Dynamic simulation of the laboratory-scale controlled ecological life support system

There are a number of design and control issues that need to be resolved in order to make a crop growth chamber an integral part of a controlled ecological life support system (CELSS) capable of supporting life on extended space missions. A modeling and simulation effort, along with the construction of an experimental testbed, are underway at NASA Ames Research Center to explore the long-term dynamic behavior of closed-loop life support systems. One problem that has been isolated for investigation is the stability and robustness of closed-loop systems over extended periods of time. Currently a crop growth chamber is being integrated with a solid waste processor to study closure of the carbon loop. A dynamic simulation model of the system was developed to evaluate system design options and operational alternatives. The model was also used to simulate the impact of system buffer size on the dynamic behavior of conditions inside the crop growth chamber.