Unraveling Complex Systems: NASA Robotic Missions to a Lunar Dark
Jet Propulsion Laboratory/Caltech
Tracy Van Houten
Last modified: September 24, 2007
The design of space missions involves the composition and integration of numerous complex engineering systems by teams of engineers from a wide variety of disciplines. Such teams typically produce singular point designs for each set of requirements or assumptions—an expensive and labor-intensive process. While automated independent models exist for each of the many subsystems, the end-to-end design process is so variable, dynamic, and dependent on mission requirements, to date it has defied attempts at automating the entire procedure. This paper describes an integrated modeling approach used to produce multiple design options for space mission designs at significantly reduced cost. More than just a model to generate numerous design points, it has enabled mission designers to unravel complex system dependencies and resolve key decisions about the power subsystem. Two mission concepts for large-scale, complex, robotic missions to search for frozen water at the lunar South Pole were systematically analyzed to identify (1) which mission provided the greatest benefit; and (2) the optimal power system technology for each mission. The model of the end-to-end process was used to generate an additional ten mission designs at a fraction of the cost and time. The model was validated in follow-on sessions by the design team in a single-blind study (the model results were not revealed to the team). The approach was viewed as an effective tool for developing a “systems-level” understanding of multiple subsystem dependencies.