Flying a satellite by a robot - First Experiences of the Automation of Station Keeping Maneuvers of a Geostationary Satellite

Kurzfassung

In 2019, the second geostationary node of the European Data Relay System (EDRS), also known as SpaceDataHighway, was successfully deployed into orbit. Considering that the control box of this EDRS-C satellite is confined to a sector of 0.05 degrees, rather than the standard 0.1 degrees, the frequency of required station-keeping maneuvers exceeds that of typical geostationary missions. To address these intensified operational activities, the EDRS control center harnesses the advanced capabilities of the ground system to automate operations. This functionality has been integrated into the ground system from the beginning of its design, because the substantial amount of commands necessary to establish up to 400 optical inter-satellite links daily surpasses the capacities of traditional manual operation systems. Consequently, an automated system had already been implemented that requires human intervention solely in instances of anomalies in either ground processing or the space segments. Building upon this automated system for payload operations and the pre-existing manual station-keeping procedures, an innovative methodology has been devised to execute maneuvers autonomously. This approach remains anchored in human-readable Flight Operations Procedures (FOPs), which is essential for maintaining situational awareness should any issues arise during execution. In the absence of issues, the concept foresees only periodic monitoring at specific points in the timeline by the operator. Following its implementation, the automated process underwent a six-month period of rigorous monitoring to attain validation. This extensive validation phase was required to identify very minor timing issues that are negligible when a human operator executes a procedure but pose a significant risk of stumbling for an automated system. Using the knowledge gained from the validation period, the automated FOPs were refined to address these minor issues, and the flight operations team received training to manage potential problems during automated execution. With only minor issues detected during validation, the approach has transitioned to operational status and is in routine use ever since. This paper delineates the design of the existing automated system within the Satellite Control Center (SCC) used to automate Station Keeping Maneuvers (SKM). In addition, the implementation and validation process is detailed, and the first 12 months of operational use are evaluated with respect to reliability and efficiency. With the station-keeping maneuvers of EDRS-C executed in a classical manual way for the first four years of operations, a comparison between the two methodologies is elaborated. This novel approach represents not only a significant innovative leap in systems for operational automatizing but also in optimizing the limited time of the operator. Therefore, the paper does not only focus on technical aspects but examine the operational advantages and challenges of this methodology for the control centers staff as well.