Validating Human Performance Models of the Future Orion Crew Exploration Vehicle

NASA's Orion Crew Exploration Vehicle (CEV) will provide transportation for crew and cargo to and from destinations in support of the Constellation Architecture Design Reference Missions. Discrete Event Simulation (DES) modeling is one of the design methods NASA employs to estimate crew performance in the CEV. During the early development of the CEV, NASA and its prime Orion contractor Lockheed Martin (LM) sought out an effective, low-cost method for developing and validating human performance DES models. This paper focuses on the method developed while creating a DES model for the Rendezvous, Proximity Operations, and Docking (RPOD) phase to the International Space Station. Our approach to validation was to attack the problem from several fronts. First, we began the development of the model early in the CEV design stage. Second, we adhered to NASA's modeling and simulation development standards. Third, we involved the stakeholders, NASA astronauts, subject matter experts, and NASA's modeling and simulation development community throughout. Fourth, we applied standard and repeatable methods to ensure the model's accuracy. Lastly, we applied the data from a separate human-in-the-loop RPOD simulation, which provided us an additional means to estimate the validity of the model. The results showed that a majority of the DES model was an accurate representation of the current CEV design.