Mission Planning Technology

For over five decades, DLR/GSOC has been responsible for the preparation and execution of many manned and unmanned space missions. Effective and professional planning for the spacecraft as well as related on-ground activities always is an essential factor for the mission success.

Mission Planning is a highly complex process which comprises

• collecting and analyzing of information, resources and requirements
• sophisticated, intelligent and fast tools to support mission preparation as well as mission execution tasks
• planning of all onboard and related on-ground activities
• automated or interactive frequent generation of the mission timeline
• production and distribution of all necessary outputs (e.g. command sequences for the spacecraft, or ground station usage plan) and documentation

On the one hand, the experienced scientists of the GSOC Mission Planning team (DLR group RB-MIT-MIP) have developed an own generic planning framework for the optimization and coordination of all activities onboard a spacecraft. It is continuously enhanced by adopting new planning concepts to meet new requirements. This can mean updates on a short notice for already active systems by adaptations of the configuration of planning rules and constraints, but also changes in the overall design for long-term projects.
On the other hand, the Mission Planning team often develops and operates additional project-specific software components that fit the respective mission needs and together with or based on the generic components form the Mission Planning systems of these missions.

An overview of the product and service portfolio of the GSOC Mission Planning team in pdf format can be found here.

Extracted to a short video, here also a quick overview of the "Cutting-edge Software Applications for Mission Operations" of the whole Mission Technology department (RB-MIT) incl. the MIP components can be gained (published June 2021).

Filmisch aufbereitet kann man zudem hier einen knappen Überblick über die verschiedensten Software-Anwendungen der gesamten Abteilung Missionstechnologie (RB-MIT) incl. der MIP-Komponenten gewinnen. (Stand: Juni 2021)

The generic GSOC planning framework is a well-established and well-proven tool suite,

• successfully applied in manned missions like Spacelab, D-2, X-SAR/SRTM, MIR,
• equally successfully deployed during scientific satellite missions (e.g. CHAMP, GRACE 1&2, TerraSAR-X and TanDEM-X, FireBird, Eu:CROPIS, Grace-FO, EnMAP)
• successfully used within the commercial missions TDP-1, EDRS-A&-C, PAZ and SmallGEO HAG-1 (for the latter two, LEOP and commissioning activities only), and
• being applied as support components at external entities within licence contracts.

This tool suite can be configured in various ways to serve a broad range of mission requirements. Its main components currently are:

• Reactive Planning Framework - the generic planning system components, services and infrastructure
  To be prepared for the requirements of new spacecraft missions, a new Mission Planning framework has been developed and is continuously extended aiming for highly reactive planning and commanding capabilities. In this scope, a robust, scalable, extensively configurable tool suite has been established including novel persistence mechanisms which now is applied for various automated and semi-automated mission planning systems. See also "The Incremental Planning System" as well as "The EnMAP Mission Planning System" and "Replacing the TDP-1 Mission Planning System" in the list of publications.
• Plains – the novel core library for modeling and planning
  The development of an upgraded version of the PLATO library (see below) in the Scala programming language allowed for a re-design and extension of the underlying planning model, algorithmic concepts and functionalities for every new planning system developed at GSOC, inherently included in the Reactive Planning framework.
• PintaOnWeb - the novel core tool for inspection and interaction
  This aims to combine and replace our current generic tools PINTA and TimOnWeb (see below) to be prepared for the requirements of new missions and additional applications. PintaOnWeb uses novel Web development techniques and frameworks and is based on the Reactive Planning framework and the Plains library within its backend. This ensures to combine all the advantages and to provide an interactive, robust, and scalable overall Mission Planning operations tool-box.
  Furthermore, accessing the SCOTA services and also a combination with SPOTOnWeb (see SPOT) is foreseen for providing an even more user-friendly, hollistic, but freely recombinable tool suite for all kinds of future spacecraft missions and Mission Planning applications.
• SCOTA (SpaceCraft Orbit and groundTrack Analysis tool) - the most recent generation of mission analysis and event calculation software
  SCOTA supports the most commonly used orbit propagator models (SGP4, SGP8, etc.) for various mission requirements. Depending on the trajectory and attitude of the considered spacecraft, its instrument capabilities, as well as the Earth and the Sun, a variety of events needed within Mission Planning can be calculated. Examples for these events are: day/night periods, satellite visibility and target visibilities, with or without consideration of an elevation model. The software supports various output formats, including the spacecraft grountrack visualization, and can be included as a library, via its services or as a stand-alone application feature.
• SPOT (Swath Preview and Ordering Tool) – an interactive visualization and ordering tool
  SPOT is a graphical user interface provided with functions from the SCOTA library. It allows the visualization of satellite swaths for chosen maximum looking angles. The user can also apply it to calculate target visibilities of dedicated spacecraft based on the available TwoLineElements (TLEs) and pre-configured imaging modes and to display these on an interactive map. Furthermore, it prepares consistent PlanningRequests from the chosen target acquisition opportunities, which can be sent to the planning and scheduling system of the according mission and contain all necessary planning information.
  In the near future, the SPOT functionalities will be migrated to the so-called SPOTOnWeb and then generically extended.
• PLATO – an extremely fast and intelligent scheduling library
  The strengths of PLATO are the flexible and descriptive modeling capabilities and the high-performant, multi-threaded engine with extensive support for creating custom algorithms. Generic algorithms are available, which can be combined and extended using a dedicated plug-in mechanism, and thus can be used to cover the common scheduling requirements. PLATO may be used as a ‚stand-alone’ library within fully automated planning systems (current examples: TerraSAR-X and TanDEM-X, TDP-1, EDRS-A&-C), or may be invoked within semi-automated planning systems (as for most other missions operated at GSOC).
• PINTA (Program for Interactive Timeline Analysis) – an interactive planning and visualization tool
  PINTA is optimally suitable for performing the planning process, from its modelling including the definition of resources, tasks and constraints up to semi-automated time-based scheduling. With the aid of conflict indicators and resource usage visualization, furthermore an intuitive and straight-forward manual timeline modification is possible. Besides providing numerous generic and highly configurable information import and export functionalities and a plug-in mechanism for project-specific extensions, PINTA provides an interface to the mission planning database and the PLATO library as well as the SCOTA library.
• SoEEditor (Sequence of Events Editor) - a special configuration of PINTA for the preparation and support of performing the special activities that have to be planned and re-planned during the LEOP of a mission and its simulations beforehand. For the future, a migration of these functionalities to PintaOnWeb is foreseen.
• TimOnWeb (Timeline On Web) – a flexible visualization tool for the mission timeline, based on the PINTA and PLATO libraries.

This tool suite is continuously enhanced. Since 2022, for instance the InTAS-Software is developed for "Integrated Terminal and Antenna Scheduling". This builds on PintaOnWeb, Reactive Planning, Plains, SCOTA as well as our previous experience with ground station and optical link planning and cloud coverage prediction, and addresses the challenges of planning for radio frequency as well as laser communication, and communication between ground and space as well as in-between satellites.

Moreover, the GSOC Mission Planning team is also engaged in the development of Mission Planning software on the field of onboard planning autonomy:

• The goal is to make as much use of the resources given onboard a spacecraft as possible and to enable reacting to events that haven’t been known during the ground-based planning run. Such events can include cloud coverage or to the detection of interesting contents in newly acquired data. Therefore, an additional software component shall be embedded into the onboard software that performs near-real-time re-planning and re-commanding. This happens without creating conflicts on constraints or disturbing the ground-generated base command-timeline for the ‘conventional’ Earth observation mission that has to take place in parallel. To achieve this, the onboard component is assisted by respectively extended functions of the ground Mission Planning, which prepare complex calculations in advance and provide the results via tele-commands. One of the projects on this topic was the preparation of the VAMOS experiment ("Verification of Autonomous Mission planning Onboard a Spacecraft") on the BIROS satellite (part of the FireBird mission), where, on the one hand, new activities were to be prepared by virtue of on-board detected events and, on the other hand, all on-ground and on-board prepared activities were to be checked for feasibility in real-time and executed if indicated. After this could not become operational due to spacecraft issues, the next planned milestone for this topic is now the concept validation via the OBETTE experiment ("OnBoard Event-Triggered Timeline Extension") in the scope of the SeRANIS mission.

Furthermore, the GSOC Mission Planning team also works on quantum computing techniques:

• In the future, quantum computers will allow solving specific problems faster, for example combinatorial optimization problems with constraints. As many algorithmic solutions in mission planning become very calculation intensive with larger problem sizes, the GSOC Mission Planning team tries to develop modern quantum algorithms and incorporate them into operations already now. Among others, topics include scheduling of on-call plans for a large amount of mission operators, ground station scheduling of large satellite constellations and data acquisition planning for an Earth observation mission. This is done e.g. as part of the project Quantum Mission Planning Challenges, see QMPC.