PLEXIL (Plan Execution Interchange Language) is an open source technology for automation, created and currently in development by NASA.
PLEXIL is a programming language for representing plans for automation.
PLEXIL is used in automation technologies such as the NASA K10 rover, Mars Curiosity rover's percussion drill, Deep Space Habitat and Habitat Demonstration Unit, Edison Demonstration of Smallsat Networks, LADEE, Autonomy Operating System (AOS) and procedure automation for the International Space Station.
PLEXIL has been used to demonstrate automation technologies targeted at future NASA space missions.
The binaries and documentation are widely available as BSD licensed open source from SourceForge.net.