ASAP: Autonomy through on-board planning

Usually a satellite is entirely controlled from ground. Its tasks are planned in advance by a satellite operations team using specialized scheduling software. When the orbiting satellite enters the transmission range of the ground station, communication is possible, and a newly generated plan (if required) can be uploaded and executed in due time. Although this approach is well-established and has been used for decades, it has some major drawbacks. It binds resources (e.g. personal staff, communication links, etc.) and prohibits fast reactions to transient events, due to the required change of the currently active plan. In the traditional approach, the changes can only be achieved by transmitting a new plan from the ground station to the satellite. This communication imposes time delays which are not acceptable for fast reactions and responses. A way to overcome this problem is to equip the satellite with an autonomous decision-making system which is able to alter the operation plan onboard the satellite. The department of Computer Science VIII of the University of Wuerzburg is currently developing such a system named ASAP and will present it in this paper. The focus lies on the interaction between ASAP and the OnBoard-Computer of the satellite.