Feedback from execution of a plan is used to update the plan continuously.

Continuous Activity Scheduling Planning Execution and Replanning (CASPER) is a computer program for automated planning of interdependent activities within a system subject to requirements, constraints, and limitations on resources. Now at the prototype stage of development, CASPER was conceived to enable a robotic exploratory spacecraft to perform onboard, autonomous planning and replanning of scientific observations and other functions in response to diverse unanticipated phenomena that could include unknown or changing environmental conditions, equipment failures, and errors in mathematical models used in planning. On Earth, CASPER could be adapted to use in scheduling operations of production lines and other complex systems.