Software for Planning and Execution in an Autonomous System

A software system for planning and execution of actions by an autonomous spacecraft engaged in scientific exploration has been developed to satisfy requirements to (1) maintain positive resource margins and avoid short-sighted decisions in order to achieve long-term scientific and engineering goals while (2) responding quickly to changing circumstances in order to take advantage of unexpected opportunities for gathering scientific data or to recover from equipment malfunctions or adverse environmental events. The software is based on an integrated planning-and-execution architecture that supports continuous modification of a current working plan in response to continuously arriving updated information on the activities, resources, and the state of the spacecraft and its environment. After each update, its effects are propagated through current projections, which are limited in order to avoid unnecessary work. When conflicts arise in the plan as modified pursuant to the updates, iterative repair and local-search techniques are used to resolve the conflicts.