23 research outputs found
Robust Commanding
In this paper we present Robust Commanding as a new method that mission planning
systems can implement to improve the reaction of the planning system to unsuccessful
commanding. This method can be used to improve upon
flexibility and reaction time
of the mission planning while maintaining a safe commanding concept that avoids gaps
in the mission timeline. The prerequisites are highlighted and the method is presented
and exemplified on the basis of commanding low-earth orbiting satellites. The necessary
commanding interfaces are discussed and an outlook for application of this method to future
satellite missions is given
Automated Planning versus Manual Operations in the context of the Link Management System for EDRS - SpaceDataHighway
The Link Management System (LMS) is the automated planning system for the EDRS (European Data Relay System) - SpaceDataHighway payloads at the German Space Operations Center (GSOC) and has been in continuous use since 2016. Recently, it has been extended to include the EDRS-C mission, scheduled to launch in 2019, besides EDRS-A. In this paper we discuss lessons learned and take-aways for multi-mission development of planning software as well as operations of automated planning systems. The interplay between automation and manual intervention in the LMS case is explained in multiple examples giving rise to suggestions for future development of automated planning systems. Furthermore, the LMS is described in the context of CCSDS. This paper builds on and extends (Gottfert et al. 2018)
The Algorithm Assembly Set of Plato
Driven by the requirements of earth observing satellite missions, the mission planning team of the German
Space Operations Center (GSOC) has improved its scheduling engine to allow automated timeline generation
for multiple interacting satellites. Whereas the past work included extensions of the modeling language and
improvements on the performance, current work focusses on the algorithm framework. In order to allow
future missions’ scheduling software to reuse generic algorithms, special attention is given to the way one can
add new sub-algorithms and combine them with existing ones.
This ePoster demonstrates the algorithm framework of GSOC’s mission planning software Plato, using its
interactive GUI Pinta. Based upon a typical multiple satellite planning problem, a priority based generic
algorithm is presented, which solves this problem. We show how this algorithm can be split up into small subalgorithms,
each of which can be used separately and all of which can be combined in arbitrary ways. We
demonstrate how this flexibility can be used to create modifications on the overall algorithm or include
mission specific sub-algorithms. Although all presented algorithms are based on simple heuristics, this
mechanism supplies a straight forward way to incorporate more sophisticated optimization algorithms.
The techniques demonstrated in this paper will be shown by means of the OnCall planning project. This
project is used by GSOC in order to schedule the on-call shift times of its staff in order to implement 24/7
support for all important satellite sub-systems
GSOC SoE-Editor 2.0 - A Generic Sequence of Events Tool
At the German Space Operations Center (GSOC) two applications had been developed for scheduling operations of Launch and Early Orbit Phases (LEOP), Commissioning Phases or special operations campaigns (e.g. software upload, special orbit maneuvers, etc.): one for low earth orbit (LEO) and one for medium (MEO) and geostationary earth orbit (GEO). The experiences of these tools were now merged with the scheduling capabilities of GSOC's generic mission planning application Pinta (Program for interactive timeline analysis), its scheduling library Plato (Planning tool) and the GSOC web based timeline display TimOnWeb
The Incremental Planning System – GSOC’s Next Generation Mission Planning Framework
The paper at hand presents the new generic framework for automated planning and scheduling in future mission planning systems developed at GSOC (German Space Operations Center). It evolved from the experiences made in past and current projects and the evaluation of internal and external requirements for upcoming projects. In customary systems such as the one used within GSOC’s TerraSAR-X/TanDEM-X mission, succeeding planning runs to combine all collected input to a consistent, conflict-free command timeline take place at fix, dedicated points in time, e.g. twice a day. In contrast and as a main difference, with the new system each new input is processed immediately and so a consistent up-to-date timeline is maintained at all times. We show that this approach provides a set of important advantages and new possibilities for spacecraft commanding and user satisfaction. For example, uplink schedules can be flexibly modified due to short-term notifications, or up-to-date, extensive information about the planning state is always available, which means that conflicts can be seen before finally submitting a new request and, if applicable, can be resolved by selecting a suggested solution scenario. The presented system constitutes a generic tool suite which is scalable in performance critical areas, which is configurable to various mission scenarios and which defines a dedicated set of interfaces, specifying the functionality that remains to be implemented by each individual project. The declared goal is that all upcoming GSOC missions will benefit from using the Incremental Planning framework in terms of cost reduction, implementation duration and system robustness
GSOCs Planning Library: History, Generic Features and Lessons Learnt
Mission Planning at GSOC started, in cooperation with other agencies, with manually triggered processes. Within the mission D-2, first experiences have been gathered with the Experiment Scheduling Program of the Marshall Space Flight Center. For succeeding missions, the interactive planning application Pinta has been developed, together with additional tools which support event calculation and automated planning using simple heuristics. A major step forward was the implementation of a fully automated planning system for TerraSAR-X, where it was in charge of the whole mission, including payload and bus. Soon this Mission Planning system had been extended to also include a second satellite and additional mission goals for the TanDEM-X mission. In preparation of a successor mission, desires of internal and external users and operators of the TerraSAR-X/TanDEM-X missions have been analyzed. Even though no successor mission for TerraSAR-X has been selected yet, the Mission Planning team evolved its planning libraries according to the outcome of this analysis and to respond to further lessons learnt, which had been gathered in different other missions throughout the years, such as FireBird, EDRS, Galileo and several LEOPs. This paper describes how GSOCs planning libraries evolved, presents the current status, and presents the current status. It discusses what generic features have proven beneficial, which features were less helpful, and describes obstacles which need to be considered in different missions. The paper concludes with an outlook on how the GSOC Mission Planning team prepares its systems for the future
Towards Generic Planning of Optical Links
The paper at hand presents our concept for upcoming space-ground optical Mission Planning systems at DLR GSOC. In cooperation with TESAT we have more than 15 years of operational experience for optical links. We have thoroughly discussed challenges and needs of optical mission planning systems to enable potential customers for deployment of full end-to-end systems. While earlier systems such as TDP-1 (Technical Demonstration Project) or EDRS (European Data Relay System) had individual requirements and interfaces, the new system is capable to consider ad-hoc additional requirements and generic interfaces. This flexibility is a big step towards our goal of a fully interoperable control center infrastructure. We show in the paper at hand how the new concept will be implemented and validated. The developed architecture is based upon the "Program for INteractive Timeline Analysis" (PINTA). PINTA enables the User in this specific use case to manually schedule links from a set of precalculated visibilities and trigger an automated link export for both optical terminals (on ground and in orbit) for their execution. At first, PINTA will be used offline for scheduling the links of the new DLR optical ground station AlmerÃa; in the frame of the Global Optical Ground Station Network (GlobeON). The subsequent development step will result in embedding these functionalities in another architecture which builds upon the new generic interfaces, replacing PINTA with the GSOC's generic Reactive Planning framework and its frontend PintaOnWeb for visual support, modification and analysis. This tool suite will allow for automatically triggered incremental planning runs immediately upon reception of new input (e.g. orbit updates, spacecraft and ground station unavailability) instead of manually initiated runs or semi-automated planning at fixed intervals. Finally, more elaborated interactions with the spacecraft and ground station operations and the prediction as well as real-time information about local weather conditions are aimed to be included into the automated planning process
Evaluating the new CCSDS mission planning and scheduling standard: how TGO and EnMAP could have benefitted from an interoperability standard for the exchange of mission planning and scheduling information
Work on the CCSDS Mission Planning and Scheduling (MPS) standard is currently nearing completion. This paper starts with providing a thorough introduction to the standard and then assesses how the upcoming MPS standard could potentially improve the interoperability of actual space missions. In this respect it will provide an evaluation of how the standard could potentially be applied in two missions currently in orbit, ESAs Mars Trace Gas Orbiter (TGO) and DLRs Earth Observation mission EnMAP. In the meantime, an additional evaluation of ESAs OPS-SAT mission has become available and has been included in the paper. As part of the analysis, first the most relevant interfaces of each mission will be described. It is then discussed how these interfaces could potentially be mapped onto CCSDS MPS service operations. Finally, it is assessed what would be the advantages of this new approach and where project-specific challenges remain. In addition, shortcoming will be identified, either with the MPS standard itself or in general with related CCSDS standards that are applicable to the mission ground segment
Ground Assisted Onboard Planning Autonomy with VAMOS
The typical ground based mission planning system for a
low earth satellite mission has one major drawback: The
reaction time to onboard detected events includes at least
the two upcoming ground station contacts.
To address this disadvantage, DLR/GSOC implements the
software experiment VAMOS as part of the FireBIRD
mission, in which mission planning autonomy will be
transferred to the spacecraft up to some extent. This paper
presents the outcome of the VAMOS design phase – a
concept of minimized onboard complexity which allows
onboard reaction to telemetry measurements and event
detection. In order to minimize risks and the computational
effort onboard a solution has been chosen that demands
relatively simple tasks of the onboard autonomy but
nevertheless will lead to maximizing the mission output
and still takes care of all potentially to be considered
resource constraints
VAMOS – Verification of Autonomous Mission Planning On-board a Spacecraft
For typical ground based mission planning systems for low earth satellite missions one major drawback can be detected: The reaction time to on-board-detected events, which includes at least two ground station contacts. To correct this, the DLR/GSOC invented VAMOS, which is an autonomous concept of minimized on-board complexity which allows on-board reaction to telemetry measurements and event detection. This experiment will be part of the FireBIRD mission and verify the gain when mission planning autonomy is transferred to the spacecraft up to some extent. This paper presents the outcome of the design phase under the given constraints. In order to minimize risks and computational effort on-board, a solution has been chosen that demands relatively simple tasks of the on-board autonomy but nevertheless will lead to maximizing the mission output and on the other hand takes care of all potentially to be considered resource constraints