Incorporating High-Speed, Optimizing Scheduling into NASA's EUROPA Planning Architecture

This paper describes an effort investigating improvements possible to NASA’s EUROPA planning system development toolset through the addition of high-speed, high-quality scheduling algorithms. We determined that such additions were beneficial, feasible, and could be readily taken advantage of by planning system developers. We designed two different integration mechanisms (re-implementation of scheduling algorithms within EUROPA and interfacing an existing c++ library of scheduling algorithms to EUROPA), determined that there were advantages to each approach. We prototyped the reimplementation integration option and showed its benefits with two prototypes – one directed toward International Space Station (ISS) Extravehicular Activity (EVA) planning (that showed significantly better results in less time than EUROPA operating alone) and one directed toward automatic Score ISS crew scheduling that was able to quickly, automatically schedule with realistic data while obeying a large number of hard and soft constraints. (No automatic Score ISS scheduling capability currently exists.) Finally, we added the scheduling-enhanced EUROPA prototype to an independently-developed EUROPA application, which allowed it to finish planning and find an optimal schedule in under 4 minutes instead of not returning at all after 80 minutes.