Layered Planning Modeal for Distributed Schedules
Stewart Hall · SpaceOps 2012 Conference · 2012
Mission Planning systems have traditionally focused on the generation of a simple queue of time-tagged telecommands.As on-board autonomy and use of ground automation increases, schedules are increasingly complex and distributed.Schedules initiate procedures and software functions as well as discrete commands and in response to orbital position or event as well as time.From an operational perspective it is important that distributed schedules are consistent and coordinated, and that there is an integrated view of the current status of operations that synthesizes the latest available information relating to all executing schedules.A layered model for Mission Planning and Schedule Execution is proposed that is capable of supporting distributed schedules and integration with automation.The focus is on representing plans and schedules as a set of abstract items describing predicted events, spacecraft contacts, planned operations, schedulable activities and the constraints between them.Operations are tagged by a triggering event, which has an abstract ID but may also be elaborated to absolute or predicted position and time.The definition of a common model of the schedule and its dynamic update allows for development of mission independent schedule displays and schedule history.The model is layered to ensure that planning is performed on a generic view of an integrated schedule, with translation of the schedule to mission specific execution formats encapsulated at the lowest layer of integration with the spacecraft and mission control system.