M.Sc. Andreas Maurer

• 6U+ CubeSat SONATE2: Operation of an Optical AI Payload in Low Earth Orbit. Herbst, Tobias; Balagurin, Oleksii; Greiner, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Schwarz, Tobias. In 75th International Astronautical Congress (IAC). 2024.
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  Optical payloads and other instruments can generate large amounts of data. Data acquisition is often limited by downlink capabilities, especially in the context of space exploration, as the NASA deep space network is said to be at capacity, for example. Intelligent onboard data processing can decrease the amount of data that has to be transferred to Earth. The Nanosatellite SONATE-2, developed and operated at the University of Würzburg, tackles this problem by demonstrating artificial intelligence technologies in a low Earth orbit. SONATE-2's AI payload has specialized hardware, featuring an NVIDIA Jetson NX System on Module (SoM) with a 6-Core ARM CPU and an NVIDIA Volta architecture GPU with Tensor cores that can infer and train neural networks. This SoM enables data processing using pre-trained models on the ground and training neural networks onboard. The Linux operating system of the AI Payload allows for the use of standard libraries, like CUDA, CudNN, or TensorFlow. The 6U+ CubeSat SONATE-2 was launched with the Transporter 10 Mission by Space X into a sun-synchronous orbit in March 2024. This work presents the results of the first months of operation of the SONATE-2 Nanosatellite. The primary mission objective is to demonstrate AI technologies in space, including anomaly detection, image segmentation, and object detection using four cameras, two in the visible spectrum and two in the near-infrared. This work focuses on the technical challenges and presents the methods used to operate the AI Payload in space. In addition, we give an overview of our experiences with managing the payload, including the thermal and power considerations. A brief outlook on the planned experiments within the mission duration of one year is presented.

  @inproceedings{herbst2024cubesat, abstract = {Optical payloads and other instruments can generate large amounts of data. Data acquisition is often limited by downlink capabilities, especially in the context of space exploration, as the NASA deep space network is said to be at capacity, for example. Intelligent onboard data processing can decrease the amount of data that has to be transferred to Earth. The Nanosatellite SONATE-2, developed and operated at the University of Würzburg, tackles this problem by demonstrating artificial intelligence technologies in a low Earth orbit. SONATE-2's AI payload has specialized hardware, featuring an NVIDIA Jetson NX System on Module (SoM) with a 6-Core ARM CPU and an NVIDIA Volta architecture GPU with Tensor cores that can infer and train neural networks. This SoM enables data processing using pre-trained models on the ground and training neural networks onboard. The Linux operating system of the AI Payload allows for the use of standard libraries, like CUDA, CudNN, or TensorFlow. The 6U+ CubeSat SONATE-2 was launched with the Transporter 10 Mission by Space X into a sun-synchronous orbit in March 2024. This work presents the results of the first months of operation of the SONATE-2 Nanosatellite. The primary mission objective is to demonstrate AI technologies in space, including anomaly detection, image segmentation, and object detection using four cameras, two in the visible spectrum and two in the near-infrared. This work focuses on the technical challenges and presents the methods used to operate the AI Payload in space. In addition, we give an overview of our experiences with managing the payload, including the thermal and power considerations. A brief outlook on the planned experiments within the mission duration of one year is presented.}, author = {Herbst, Tobias and Balagurin, Oleksii and Greiner, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Schwarz, Tobias}, booktitle = {75th International Astronautical Congress (IAC)}, keywords = {ai}, title = {6U+ CubeSat SONATE2: Operation of an Optical AI Payload in Low Earth Orbit}, year = 2024 }
• In-Orbit Validierung des MultiView-Sternsensors auf dem SONATE-2 CubeSat. Neumann, Tobias; Balagurin, Oleksii; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Riegler, Clemens; Schwarz, Tobias. In Deutscher Luft- und Raumfahrtkongress. Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Hamburg, 2024.
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  Es wurde ein mehrköpfiger Sternsensor für CubeSats für den Einsatz im sog. TunaCanSlot konzipiert. Der Sensor zeichnet sich durch die gegebene Redundanz auf Grund der Verwendung einer Vielzahl an Sensorköpfen trotz des geringen Bauvolumens aus. Im Falle eines Ausfalls oder bei fehlenden Messdaten werden die Sensoren autonom umgeschaltet, die so die Verfügbarkeit der Lagedaten erhöht. Der MultiViewSternsensor wurde an Bord des SONATE2 Nanosatelliten Anfang März 2024 in die Erdumlaufbahn gebracht. Neben anderen Subsystemen als Technologiedemonstration, wurde der Sensor während der Missionslaufzeit in Betrieb genommen und bereits mehreren Tests unterzogen. Damit wird die Raumfahrttauglichkeit sowie der Einsatz im LowEarth Orbit nachgewiesen. In diesem Paper werden die für die Validierung benötigten Aspekte dargestellt. Wichtig sind die Überprüfungen sowohl der Grundfunktionen als Subsystem gegenüber dem Satelliten, als auch der Messprozesse der Sensorköpfe selbst. Die bisherigen Ergebnisse der InOrbitTests werden in Verbindung mit den dargestellten Validierungsaspekten präsentiert. Sie bestätigen die Funktion des Konzeptes und bilden bereits eine gute Grundlage für die in Aussicht gestellte Validierung auf TRL 9.

  @inproceedings{neumann2024inorbit, abstract = {Es wurde ein mehrköpfiger Sternsensor für CubeSats für den Einsatz im sog. TunaCanSlot konzipiert. Der Sensor zeichnet sich durch die gegebene Redundanz auf Grund der Verwendung einer Vielzahl an Sensorköpfen trotz des geringen Bauvolumens aus. Im Falle eines Ausfalls oder bei fehlenden Messdaten werden die Sensoren autonom umgeschaltet, die so die Verfügbarkeit der Lagedaten erhöht. Der MultiViewSternsensor wurde an Bord des SONATE2 Nanosatelliten Anfang März 2024 in die Erdumlaufbahn gebracht. Neben anderen Subsystemen als Technologiedemonstration, wurde der Sensor während der Missionslaufzeit in Betrieb genommen und bereits mehreren Tests unterzogen. Damit wird die Raumfahrttauglichkeit sowie der Einsatz im LowEarth Orbit nachgewiesen. In diesem Paper werden die für die Validierung benötigten Aspekte dargestellt. Wichtig sind die Überprüfungen sowohl der Grundfunktionen als Subsystem gegenüber dem Satelliten, als auch der Messprozesse der Sensorköpfe selbst. Die bisherigen Ergebnisse der InOrbitTests werden in Verbindung mit den dargestellten Validierungsaspekten präsentiert. Sie bestätigen die Funktion des Konzeptes und bilden bereits eine gute Grundlage für die in Aussicht gestellte Validierung auf TRL 9.}, address = {Hamburg}, author = {Neumann, Tobias and Balagurin, Oleksii and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Riegler, Clemens and Schwarz, Tobias}, booktitle = {Deutscher Luft- und Raumfahrtkongress}, keywords = {cubesat}, publisher = {Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, title = {In-Orbit Validierung des MultiView-Sternsensors auf dem SONATE-2 CubeSat}, year = 2024 }
• Novel On-Board Data Processing Strategies on Nanosatellite SONATE-2. Maurer, Andreas; Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Schwarz, Tobias. In Small Satellites, System & Services Symposium (4S). Palma de Mallorca, Spain, 2024.
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  Reliable on-board data handling is the backbone of every successful satellite mission. New scientific experiments can only be validated, and results obtained, if the recorded scientific data reaches the ground completely and correctly. For this, several special techniques were applied during the implementation of the SONATE-2 mission. Generic communication protocols were defined between all payloads, subsystems, and the On-board data handling (OBDH) of SONATE-2 to reduce the overall complexity of the data management system. With the help of these protocols, the development effort could be reduced, and the data transfers simplified. In addition, this allowed the communication interfaces to be simulated and quickly tested during development with a desktop computer using an OBDH-Simulator.

  @conference{maurerandreas2024novel, abstract = {Reliable on-board data handling is the backbone of every successful satellite mission. New scientific experiments can only be validated, and results obtained, if the recorded scientific data reaches the ground completely and correctly. For this, several special techniques were applied during the implementation of the SONATE-2 mission. Generic communication protocols were defined between all payloads, subsystems, and the On-board data handling (OBDH) of SONATE-2 to reduce the overall complexity of the data management system. With the help of these protocols, the development effort could be reduced, and the data transfers simplified. In addition, this allowed the communication interfaces to be simulated and quickly tested during development with a desktop computer using an OBDH-Simulator.}, address = {Palma de Mallorca, Spain}, author = {Maurer, Andreas and Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Schwarz, Tobias}, booktitle = {Small Satellites, System & Services Symposium (4S)}, keywords = {obdh}, title = {Novel On-Board Data Processing Strategies on Nanosatellite SONATE-2}, year = 2024 }
• Early Results and In-Flight Experience of the 6U-Mission SONATE-2. Schwarz, Tobias; Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas. In Small Satellites, System & Services Symposium (4S). Palma de Mallorca, Spain, 2024.
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  SONATE-2 is a 6U+ CubeSat for technology demonstration developed at the University of Würzburg. It was launched on SpaceX' Transporter-10 mission into a 527x505 km Sun synchronous orbit on March 4, 2024.

  @inproceedings{schwarzEARLYRESULTSINFLIGHT2024, abstract = {SONATE-2 is a 6U+ CubeSat for technology demonstration developed at the University of Würzburg. It was launched on SpaceX' Transporter-10 mission into a 527x505 km Sun synchronous orbit on March 4, 2024.}, address = {Palma de Mallorca, Spain}, author = {Schwarz, Tobias and Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas}, booktitle = {Small Satellites, System & Services Symposium (4S)}, keywords = {results}, title = {Early Results and In-Flight Experience of the 6U-Mission SONATE-2}, year = 2024 }
• Erste Flugergebnisse der Satellitenmission SONATE-2. Balagurin, O.; Greiner, T.; Herbst, T.; Kaiser, T.; Kayal, H.; Männel, J.; Maurer, A.; Neumann, T.; Riegler, C.; Schwarz, T. In Deutscher Luft- und Raumfahrtkongress. Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Hamburg, 2024.
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  SONATE-2 ist eine Technologiedemonstrationsmission im 6U -CubeSat-Format, deren Hauptziel es ist, neuartige Methoden der künstlichen Intelligenz für den Einsatz auf Nanosatelliten im Orbit zu verifizieren. Nach etwa drei Jahren Entwicklungszeit wurde der SONATE-2-Satellit Anfang März 2024 durch eine Falcon-9-Rakete in den Low Earth Orbit befördert und wird seitdem vom eigenen Missionskontrollzentrum der Uni-versität Würzburg betrieben. Dieses Paper fasst die Ergebnisse der ersten fünf Monate des Satellitenbe-triebs zusammen.

  @inproceedings{https://doi.org/10.25967/630218, abstract = {SONATE-2 ist eine Technologiedemonstrationsmission im 6U -CubeSat-Format, deren Hauptziel es ist, neuartige Methoden der künstlichen Intelligenz für den Einsatz auf Nanosatelliten im Orbit zu verifizieren. Nach etwa drei Jahren Entwicklungszeit wurde der SONATE-2-Satellit Anfang März 2024 durch eine Falcon-9-Rakete in den Low Earth Orbit befördert und wird seitdem vom eigenen Missionskontrollzentrum der Uni-versität Würzburg betrieben. Dieses Paper fasst die Ergebnisse der ersten fünf Monate des Satellitenbe-triebs zusammen.}, address = {Hamburg}, author = {Balagurin, O. and Greiner, T. and Herbst, T. and Kaiser, T. and Kayal, H. and Männel, J. and Maurer, A. and Neumann, T. and Riegler, C. and Schwarz, T.}, booktitle = {Deutscher Luft- und Raumfahrtkongress}, keywords = {cubesat}, publisher = {Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, title = {Erste Flugergebnisse der Satellitenmission SONATE-2}, year = 2024 }

• SONATE-2 – Using Artificial Intelligence for In-Orbit Image Processing and Anomaly Detection. Greiner, Tobias; Balagurin, Oleksii; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Schwarz, Tobias. In 14th IAA Symposium on Small Satellites for Earth Observation. Berlin, 2023.
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  @inproceedings{greiner2023sonate2, address = {Berlin}, author = {Greiner, Tobias and Balagurin, Oleksii and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Schwarz, Tobias}, booktitle = {14th IAA Symposium on Small Satellites for Earth Observation}, keywords = {ai}, title = {SONATE-2 – Using Artificial Intelligence for In-Orbit Image Processing and Anomaly Detection}, year = 2023 }
• SONATE-2 – A Technology Demonstration Mission of Artificial Intelligence for Image Processing and Anomaly Detection. Greiner, Tobias; Balagurin, Oleksii; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Schwarz, Tobias. In 16th Pico- and Nano-Satellite Workshop. Würzburg, Germany, 2023.
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  @conference{greiner2023sonate2, address = {Würzburg, Germany}, author = {Greiner, Tobias and Balagurin, Oleksii and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Schwarz, Tobias}, booktitle = {16th Pico- and Nano-Satellite Workshop}, keywords = {ai}, title = {SONATE-2 – A Technology Demonstration Mission of Artificial Intelligence for Image Processing and Anomaly Detection}, year = 2023 }
• Attitude-independent calibration of magnetometers in orbit using Particle Swarm Optimization. Kaiser, Tobias; Thois, Dominik; Balagurin, Oleksii; Greiner, Tobias; Kayal, Hakan; Schwarz, Tobias; Maurer, Andreas; Herbst, Tobias; Riegler, Clemens. In 14th IAA Symposium on Small Satellites for Earth Observation. 2023.
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  SONATE-2 is an upcoming CubeSat for AI applications in space. The payload includes widefield and nearfield cameras to take images of the Earth and perform tasks like image segmentation and anomaly detection. The Attitude Determination and Control System (ADCS) is designed to provide accurate pointing for these tasks. In addition, a propulsion system and a star sensor will be validated in orbit. In normal operations, the magnetic field vector and the sun vector are measured to determine the CubeSat attitude via the TRIAD or QUEST method. The harsh space environment subjects the sensors to disturbances, and it is expected that the calibration parameters will change over time. The magnetometers will be recalibrated in orbit using Particle Swarm Optimization (PSO). The algorithm records the predicted and measured magnetic field vectors from hundreds of points in time and minimises the error between their magnitude by changing the calibration parameters. This calibration was tested at the JMU Würzburg on demonstrator hardware for the ADCS and a set of Helmholtz coils simulating the Earth Magnetic Field. The resulting calibration parameters were only slightly less accurate than those found by calibrating the magnetometer in the laboratory. The calibration algorithm will be optimized further and then implemented on SONATE-2.

  @inproceedings{noauthororeditorattitudeindependent, abstract = {SONATE-2 is an upcoming CubeSat for AI applications in space. The payload includes widefield and nearfield cameras to take images of the Earth and perform tasks like image segmentation and anomaly detection. The Attitude Determination and Control System (ADCS) is designed to provide accurate pointing for these tasks. In addition, a propulsion system and a star sensor will be validated in orbit. In normal operations, the magnetic field vector and the sun vector are measured to determine the CubeSat attitude via the TRIAD or QUEST method. The harsh space environment subjects the sensors to disturbances, and it is expected that the calibration parameters will change over time. The magnetometers will be recalibrated in orbit using Particle Swarm Optimization (PSO). The algorithm records the predicted and measured magnetic field vectors from hundreds of points in time and minimises the error between their magnitude by changing the calibration parameters. This calibration was tested at the JMU Würzburg on demonstrator hardware for the ADCS and a set of Helmholtz coils simulating the Earth Magnetic Field. The resulting calibration parameters were only slightly less accurate than those found by calibrating the magnetometer in the laboratory. The calibration algorithm will be optimized further and then implemented on SONATE-2.}, author = {Kaiser, Tobias and Thois, Dominik and Balagurin, Oleksii and Greiner, Tobias and Kayal, Hakan and Schwarz, Tobias and Maurer, Andreas and Herbst, Tobias and Riegler, Clemens}, booktitle = {14th IAA Symposium on Small Satellites for Earth Observation}, keywords = {adcs}, title = {Attitude-independent calibration of magnetometers in orbit using Particle Swarm Optimization}, year = 2023 }

• SONATE-2 - A Technology Demonstration Mission for Artificial Intelligence. Greiner, Tobias; Balagurin, Oleksii; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Neumann, Tobias; Riegler, Clemens; Schwarz, Tobias. In Small Satellites, System & Services Symposium (4S), G. Tobias, B. Oleksii, H. Tobias, K. Tobias, K. Hakan, M. Andreas, N. Tobias, R. Clemens, S. Tobias (eds.). Vilamoura, Portugal, 2022.
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  The increasing amount of data produced by sensors, combined with low download rates, are a challenge for nanosatellites. On-board data processing and classification can be used to reduce the amount of data that needs to be downloaded. This edge computing approach has become more and more present in various terrestrial applications and embedded devices. Recent missions have used artificial intelligence (AI) models, pre-trained on the ground, for on-board image analysis. The SONATE-2 mission expands on this approach by also introducing on-board training capabilities, enabling new applications including on-board model generation and improvement.

  @inproceedings{greiner2022sonate2, abstract = {The increasing amount of data produced by sensors, combined with low download rates, are a challenge for nanosatellites. On-board data processing and classification can be used to reduce the amount of data that needs to be downloaded. This edge computing approach has become more and more present in various terrestrial applications and embedded devices. Recent missions have used artificial intelligence (AI) models, pre-trained on the ground, for on-board image analysis. The SONATE-2 mission expands on this approach by also introducing on-board training capabilities, enabling new applications including on-board model generation and improvement.}, address = {Vilamoura, Portugal}, author = {Greiner, Tobias and Balagurin, Oleksii and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Neumann, Tobias and Riegler, Clemens and Schwarz, Tobias}, booktitle = {Small Satellites, System & Services Symposium (4S)}, editor = {Tobias, Greiner and Oleksii, Balagurin and Tobias, Herbst and Tobias, Kaiser and Hakan, Kayal and Andreas, Maurer and Tobias, Neumann and Clemens, Riegler and Tobias, Schwarz}, keywords = {ai}, title = {SONATE-2 - A Technology Demonstration Mission for Artificial Intelligence}, year = 2022 }
• In-Flight Experience and Operations of the 3U-Mission SONATE. Schwarz, Tobias; Balagurin, Oleksii; Greiner, Tobias; Kayal, Hakan; Maurer, Andreas. In Small Satellites, System & Services Symposium (4S). Vilamoura, Portugal, 2022.
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  SONATE was a 3U-CubeSat for technology demonstration developed at the University of Würzburg, primarily for the in-orbit verification of the autonomous payloads ASAP-L and ADIA-L, as well as other smaller payloads like star sensors and reaction wheels. On July 5, 2019, it was successfully launched on a Russian Soyuz rocket into a 530 km Sun synchronous orbit. The mission ended after one year of operations. During its operation, SONATE has been commanded and telemetry was received almost daily on two or three passes over the university’s ground station.

  @inproceedings{noauthororeditorinflight, abstract = {SONATE was a 3U-CubeSat for technology demonstration developed at the University of Würzburg, primarily for the in-orbit verification of the autonomous payloads ASAP-L and ADIA-L, as well as other smaller payloads like star sensors and reaction wheels. On July 5, 2019, it was successfully launched on a Russian Soyuz rocket into a 530 km Sun synchronous orbit. The mission ended after one year of operations. During its operation, SONATE has been commanded and telemetry was received almost daily on two or three passes over the university’s ground station.}, address = {Vilamoura, Portugal}, author = {Schwarz, Tobias and Balagurin, Oleksii and Greiner, Tobias and Kayal, Hakan and Maurer, Andreas}, booktitle = {Small Satellites, System & Services Symposium (4S)}, keywords = {results}, title = {In-Flight Experience and Operations of the 3U-Mission SONATE}, year = 2022 }
• Hardware and Software Redundancy Concepts on-board of SONATE-2. Maurer, Andreas; Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Riegler, Clemens; Schwarz, Tobias. Vol. IAC 2022 congress proceedings, p. 11. International Astronautical Federation (IAF), 100 Avenue de Suffren 75015 Paris, France, 2022.
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  SONATE-2 is a 6U-CubeSat, which main mission goal is the in-orbit demonstration of a newly developed AI processing platform. Experiments running on this platform include lightening detection, image segmentation and anomaly detection in images taken by the satellite. Thereby, on-board training of neural networks for AI based image processing applications will be demonstrated. Secondary mission objectives include the verification of AOCS components, tests of the ADCS’s target-pointing capabilities and the operation of an amateur radio payload. The SONATE-2 satellite is planned to be launched into a SSO in Q1 2024. par In satellites, redundancy plays a key role due to the lack of hardware-based maintenance availability, but also because of the harsh space environment. Therefore, SONATE-2 consists of two fully redundant 5V and 12V busses which supply the satellite’s subsystems and payloads with the required amount of power. Redundant subsystems are connected to one of the two power busses. In case of a power failure on one of the two busses, the redundant component supplied by the other bus is then still operational. par A key element of the design of SONATE-2 is hardware-based redundancy of the communication subsystem, the ADCS, the OBDH and the AI payload. Each of these subsystems is included multiple times on-board. SONATE-2’s communication subsystem consists of two VHF-, two UHF- and two S-Band transceivers and antennas. The ADCS includes two processing computers and a total of four three-axis magnetometers, four three-axis gyroscopes, six reaction wheel, six magnetorquer and 12 sun sensors. On-board data handling tasks are executed by one of four available OBDH computers. The decision which OBDH is executing the telecommand processing and housekeeping tasks is determined by a software-based role arbitration. Furthermore, the AI-payload which consists of a Nvidia Jetson Xavier NX and four cameras is integrated in the satellite twice. par Each of these subsystems have further built-in software-based redundancy concepts, including fault detection, isolation, and recovery algorithms as well as redundant saved configurations. This paper gives a brief overview of the SONATE-2 mission with the focus on the built-in hardware and software redundancy concepts of the satellite bus and the payloads on SONATE-2.

  @conference{maurer2022hardware, abstract = {SONATE-2 is a 6U-CubeSat, which main mission goal is the in-orbit demonstration of a newly developed AI processing platform. Experiments running on this platform include lightening detection, image segmentation and anomaly detection in images taken by the satellite. Thereby, on-board training of neural networks for AI based image processing applications will be demonstrated. Secondary mission objectives include the verification of AOCS components, tests of the ADCS’s target-pointing capabilities and the operation of an amateur radio payload. The SONATE-2 satellite is planned to be launched into a SSO in Q1 2024. \par In satellites, redundancy plays a key role due to the lack of hardware-based maintenance availability, but also because of the harsh space environment. Therefore, SONATE-2 consists of two fully redundant 5V and 12V busses which supply the satellite’s subsystems and payloads with the required amount of power. Redundant subsystems are connected to one of the two power busses. In case of a power failure on one of the two busses, the redundant component supplied by the other bus is then still operational. \par A key element of the design of SONATE-2 is hardware-based redundancy of the communication subsystem, the ADCS, the OBDH and the AI payload. Each of these subsystems is included multiple times on-board. SONATE-2’s communication subsystem consists of two VHF-, two UHF- and two S-Band transceivers and antennas. The ADCS includes two processing computers and a total of four three-axis magnetometers, four three-axis gyroscopes, six reaction wheel, six magnetorquer and 12 sun sensors. On-board data handling tasks are executed by one of four available OBDH computers. The decision which OBDH is executing the telecommand processing and housekeeping tasks is determined by a software-based role arbitration. Furthermore, the AI-payload which consists of a Nvidia Jetson Xavier NX and four cameras is integrated in the satellite twice. \par Each of these subsystems have further built-in software-based redundancy concepts, including fault detection, isolation, and recovery algorithms as well as redundant saved configurations. This paper gives a brief overview of the SONATE-2 mission with the focus on the built-in hardware and software redundancy concepts of the satellite bus and the payloads on SONATE-2.}, address = {100 Avenue de Suffren 75015 Paris, France}, author = {Maurer, Andreas and Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Riegler, Clemens and Schwarz, Tobias}, keywords = {redundancy}, month = {09}, pages = 11, publisher = {International Astronautical Federation (IAF)}, title = {Hardware and Software Redundancy Concepts on-board of SONATE-2}, volume = {IAC 2022 congress proceedings}, year = 2022 }
• Testing the NVIDIA Jetson Xavier NX Module for the SONATE-2 Nano Satellite Mission. Herbst, Tobias; Balagurin, Oleksii; Greiner, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Riegler, Clemens; Schwarz, Tobias. Vol. IAC 2022 congress proceedings, p. 7. International Astronautical Federation (IAF), 100 Avenue de Suffren 75015 Paris, France, 2022.
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  SONATE-2 is a 6U+, LEO CubeSat mission, which will demonstrate the feasibility of in-orbit image processing using neural networks. These networks shall also be trained on-board. Therefore, a powerful computational unit with a small form factor and low power consumption is needed. One possible candidate, the NVIDIA Jetson Xavier NX is analysed and tested for a possible use in this mission. Thus, thermal vacuum chamber tests, total ionizing radiation dose tests, single event effect tests and vibration tests were performed to expose the module to conditions equivalent to space environment present in LEO. The module has been Total Ionizing Dose (TID) tested with a Co-60 source at a dose of 10,krad. Single Event Effect (SEE) testing has been done with protons at energy levels of 30, 50 and 68 MeV. In addition to that, vibration tests have been conducted on acceptance level for a launch with a Soyuz-2 rocket for a containerized CubeSat. The thermal-vacuum tests included an outgassing test and a thermal cycling test with 5 cycles from -30\($^\circ$\)C to 90\($^\circ$\)C. After the TID tests, the vibration tests and the thermal tests, no damage to the module could be detected. During the outgassing test, a total mass loss of at least 0.08,% was measured. During the SEE tests, two single event effects occurred, of which one caused the device to reboot and another one caused a memory error in the modules eMMC memory. Thus, it is recommended to implement a redundancy strategy for the content of the eMMC memory and operate the device, such that spontaneous reboots do not lead to critical failures.

  @conference{noauthororeditor, abstract = {SONATE-2 is a 6U+, LEO CubeSat mission, which will demonstrate the feasibility of in-orbit image processing using neural networks. These networks shall also be trained on-board. Therefore, a powerful computational unit with a small form factor and low power consumption is needed. One possible candidate, the NVIDIA Jetson Xavier NX is analysed and tested for a possible use in this mission. Thus, thermal vacuum chamber tests, total ionizing radiation dose tests, single event effect tests and vibration tests were performed to expose the module to conditions equivalent to space environment present in LEO. The module has been Total Ionizing Dose (TID) tested with a Co-60 source at a dose of 10\,krad. Single Event Effect (SEE) testing has been done with protons at energy levels of 30, 50 and 68 MeV. In addition to that, vibration tests have been conducted on acceptance level for a launch with a Soyuz-2 rocket for a containerized CubeSat. The thermal-vacuum tests included an outgassing test and a thermal cycling test with 5 cycles from -30$^\circ$C to 90$^\circ$C. After the TID tests, the vibration tests and the thermal tests, no damage to the module could be detected. During the outgassing test, a total mass loss of at least 0.08\,\% was measured. During the SEE tests, two single event effects occurred, of which one caused the device to reboot and another one caused a memory error in the modules eMMC memory. Thus, it is recommended to implement a redundancy strategy for the content of the eMMC memory and operate the device, such that spontaneous reboots do not lead to critical failures.}, address = {100 Avenue de Suffren 75015 Paris, France}, author = {Herbst, Tobias and Balagurin, Oleksii and Greiner, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Riegler, Clemens and Schwarz, Tobias}, keywords = {ai}, pages = 7, publisher = {International Astronautical Federation (IAF)}, title = {Testing the NVIDIA Jetson Xavier NX Module for the SONATE-2 Nano Satellite Mission}, volume = {IAC 2022 congress proceedings}, year = 2022 }
• SONATE-2 Nanosatellitenmission für Künstliche Intelligenz und Höhere Autonomie. Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Riegler, Clemens; Schwarz, Tobias. In Proceedings DLRK 2022. Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn, 2022.
  • [ BibTeX ]
  @conference{balagurin2022sonate2, address = {Bonn}, author = {Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Riegler, Clemens and Schwarz, Tobias}, booktitle = {Proceedings DLRK 2022}, keywords = {ai}, month = 11, publisher = {Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, title = {SONATE-2 Nanosatellitenmission für Künstliche Intelligenz und Höhere Autonomie}, year = 2022 }
• MultiView: Koordinierter Sternsensorverbund im TunaCan-Format für CubeSats. Neumann, T.; Balagurin, O.; Baldsiefen, D.; Gerling, T.; Kaiser, T.; Kayal, H.; Maurer, A.; Riegler, C.; Schwarz, T. In Proceedings DLRK 2022, p. 7. Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn, 2022.
  • [ Abstract ]
  • [ BibTeX ]
  • [ URL ]
  • [ DOI ]
  Der Zusammenschluss mehrerer miniaturisierter Sternsensoren bietet in der richtigen Konfiguration eine stark erhöhte Verfügbarkeit an genauen Lagedaten. Das begrenzte Bauvolumen auf einem CubeSat stellt dabei eine Herausforderung dar. Die Verwendung des TunaCan-Slots, verbunden mit dem Einsatz der gegebenen hohen Sensorredundanz, ermöglicht allerdings die Realisierung eines solchen Verbundes, während die Anforderungen im Rahmen einer CubeSat-Mission bleiben. Die internen Komponenten müssen selbständig miteinander arbeiten, um die funktionale Redundanz zu bewerkstelligen. Dazu zählt sowohl die Software als auch die entsprechend entworfene Elektronik. In diesem Paper wird solch ein Konzept ausgearbeitet und die Implementierung aufgeführt. Die interne Arbeitsweise zur Redundanzsteuerung und der Datenverarbeitung wird erläutert und die Validierung zum Einsatz im Orbit in Aussicht gestellt.

  @inproceedings{neumann2022multiview, abstract = {Der Zusammenschluss mehrerer miniaturisierter Sternsensoren bietet in der richtigen Konfiguration eine stark erhöhte Verfügbarkeit an genauen Lagedaten. Das begrenzte Bauvolumen auf einem CubeSat stellt dabei eine Herausforderung dar. Die Verwendung des TunaCan-Slots, verbunden mit dem Einsatz der gegebenen hohen Sensorredundanz, ermöglicht allerdings die Realisierung eines solchen Verbundes, während die Anforderungen im Rahmen einer CubeSat-Mission bleiben. Die internen Komponenten müssen selbständig miteinander arbeiten, um die funktionale Redundanz zu bewerkstelligen. Dazu zählt sowohl die Software als auch die entsprechend entworfene Elektronik. In diesem Paper wird solch ein Konzept ausgearbeitet und die Implementierung aufgeführt. Die interne Arbeitsweise zur Redundanzsteuerung und der Datenverarbeitung wird erläutert und die Validierung zum Einsatz im Orbit in Aussicht gestellt.}, address = {Bonn}, author = {Neumann, T. and Balagurin, O. and Baldsiefen, D. and Gerling, T. and Kaiser, T. and Kayal, H. and Maurer, A. and Riegler, C. and Schwarz, T.}, booktitle = {Proceedings DLRK 2022}, keywords = {MultiView}, month = 11, pages = 7, publisher = {Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, title = {MultiView: Koordinierter Sternsensorverbund im TunaCan-Format für CubeSats}, year = 2022 }

• Entwicklung und Betrieb eines Technologieerprobungssatelliten für hochautonome Nutzlasten. Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Schwarz, Tobias. In Deutscher Luft- und Raumfahrtkongress (DLRK) 2021. Bremen, 2021.
  • [ BibTeX ]
  @conference{balagurinentwicklung, address = {Bremen}, author = {Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Schwarz, Tobias}, booktitle = {Deutscher Luft- und Raumfahrtkongress (DLRK) 2021}, keywords = {cubesat}, month = {09}, title = {Entwicklung und Betrieb eines Technologieerprobungssatelliten für hochautonome Nutzlasten}, year = 2021 }
• Development and operation of a technology testing satellite for highly autonomous payloads and artificial intelligence. Balagurin, Oleksii; Greiner, Tobias; Herbst, Tobias; Kaiser, Tobias; Kayal, Hakan; Maurer, Andreas; Neumann, Tobias; Riegler, Clemens; Schwarz, Tobias. In 14th Pico- and Nano-Satellite Workshop. Würzburg, Germany, 2021.
  • [ BibTeX ]
  @conference{noauthororeditor2021development, address = {Würzburg, Germany}, author = {Balagurin, Oleksii and Greiner, Tobias and Herbst, Tobias and Kaiser, Tobias and Kayal, Hakan and Maurer, Andreas and Neumann, Tobias and Riegler, Clemens and Schwarz, Tobias}, booktitle = {14th Pico- and Nano-Satellite Workshop}, keywords = {ai}, month = {09}, title = {Development and operation of a technology testing satellite for highly autonomous payloads and artificial intelligence}, year = 2021 }

• Methods for Multisensory Detection of Light Phenomena on the Moon as a Payload Concept for a Nanosatellite Mission. Technical Report (Master thesis), . Maurer, Andreas. Master thesis. Luleå University of Technology, Julius-Maximillians-Universität Würzburg, 2020.
  • [ Abstract ]
  • [ BibTeX ]
  • [ URL ]
  For 500 years transient light phenomena (TLP) have been observed on the lunar surface by ground-based observers. The actual physical reason for most of these events is today still unknown. Current plans of NASA and SpaceX to send astronauts back to the Moon and already successful deep-space CubeSat mission will allow in the future research nanosatellite missions to the cislunar space. This thesis presents a new hardware and software concept for a future payload on such a nanosatellite. The main task was to develop and implement a high-performance image processing algorithm which task is to detect short brightening flashes on the lunar surface. Based on a review of historic reported phenomena, possible explanation theories for these phenomena and currently active and planed ground- or space-based observatories possible reference scenarios were analyzed. From the presented scenarios one, the detection of brightening events was chosen and requirements for this scenario stated. Afterwards, possible detectors, processing computers and image processing algorithms were researched and compared regarding the specified requirements. This analysis of available algorithm was used to develop a new high-performance detection algorithm to detect transient brightening events on the Moon. The implementation of this algorithm running on the processor and the internal GPU of a MacMini achieved a framerate of 55 FPS by processing images with a resolution of 4.2 megapixel. Its functionality and performance was verified on the remote telescope operated by the Chair of Space Technology of the University of Würzburg. Furthermore, the developed algorithm was also successfully ported on the Nvidia Jetson Nano and its performance compared with a FPGA based image processing algorithm. The results were used to chose a FPGA as the main processing computer of the payload. This concept uses two backside illuminated CMOS image sensor connected to a single FPGA. On the FPGA the developed image processing algorithm should be implemented. Further work is required to realize the proposed concept in building the actual hardware and porting the developed algorithm onto this platform.

  @mastersthesis{maurer2020methods, abstract = {For 500 years transient light phenomena (TLP) have been observed on the lunar surface by ground-based observers. The actual physical reason for most of these events is today still unknown. Current plans of NASA and SpaceX to send astronauts back to the Moon and already successful deep-space CubeSat mission will allow in the future research nanosatellite missions to the cislunar space. This thesis presents a new hardware and software concept for a future payload on such a nanosatellite. The main task was to develop and implement a high-performance image processing algorithm which task is to detect short brightening flashes on the lunar surface. Based on a review of historic reported phenomena, possible explanation theories for these phenomena and currently active and planed ground- or space-based observatories possible reference scenarios were analyzed. From the presented scenarios one, the detection of brightening events was chosen and requirements for this scenario stated. Afterwards, possible detectors, processing computers and image processing algorithms were researched and compared regarding the specified requirements. This analysis of available algorithm was used to develop a new high-performance detection algorithm to detect transient brightening events on the Moon. The implementation of this algorithm running on the processor and the internal GPU of a MacMini achieved a framerate of 55 FPS by processing images with a resolution of 4.2 megapixel. Its functionality and performance was verified on the remote telescope operated by the Chair of Space Technology of the University of Würzburg. Furthermore, the developed algorithm was also successfully ported on the Nvidia Jetson Nano and its performance compared with a FPGA based image processing algorithm. The results were used to chose a FPGA as the main processing computer of the payload. This concept uses two backside illuminated CMOS image sensor connected to a single FPGA. On the FPGA the developed image processing algorithm should be implemented. Further work is required to realize the proposed concept in building the actual hardware and porting the developed algorithm onto this platform.}, author = {Maurer, Andreas}, institution = {Luleå University of Technology, Julius-Maximilians-Universität of Würzburg}, keywords = {masterthesis}, school = {Luleå University of Technology, Julius-Maximillians-Universität Würzburg}, title = {Methods for Multisensory Detection of Light Phenomena on the Moon as a Payload Concept for a Nanosatellite Mission}, year = 2020 }

• 3U satellite bus SONATE for technology demonstration of autonomous payloads,. Balagurin, Oleksii; Baumann, Tom; Greiner, Tobias; Kayal, Hakan; Maurer, Andreas; Rapp, Thomas; Schwarz, Tobias. In Proceedings of the 12th Symposium on Small Satellites for Earth Observation, Vol. 2, R. Sandau, K. Brieß, E. Gill (eds.), pp. 297–301. International Academy of Astronautics (IAA), 6 rue Galilée, Po Box 1268-16, 75766 Paris Cedex 16, France, 2019.
  • [ Abstract ]
  • [ BibTeX ]
  • [ URL ]
  SONATE is a technology demonstration mission specially designed for two particular highly autonomous payloads. These two payloads can plan and act independently of the ground segment. In order to support this autonomous operation a satellite bus with particular features was created. The main focus of this paper concentrates on the OBDH and the power generation and distribution subsystem, because the OBDH interacts strongly with the payload’s autonomous functionalities. In addition, large amounts of observation image data will be handled by the OBDH. Since the required scheduling and diagnostic algorithms are very computationally intensive, the processing electronics of the payloads consume electric power in the range of several watts. The whole satellite system was manufactured and qualified. This paper will conclude with the results of the qualification tests.

  @inproceedings{balagurin2019satellite, abstract = {SONATE is a technology demonstration mission specially designed for two particular highly autonomous payloads. These two payloads can plan and act independently of the ground segment. In order to support this autonomous operation a satellite bus with particular features was created. The main focus of this paper concentrates on the OBDH and the power generation and distribution subsystem, because the OBDH interacts strongly with the payload’s autonomous functionalities. In addition, large amounts of observation image data will be handled by the OBDH. Since the required scheduling and diagnostic algorithms are very computationally intensive, the processing electronics of the payloads consume electric power in the range of several watts. The whole satellite system was manufactured and qualified. This paper will conclude with the results of the qualification tests.}, address = {6 rue Galilée, Po Box 1268-16, 75766 Paris Cedex 16, France}, author = {Balagurin, Oleksii and Baumann, Tom and Greiner, Tobias and Kayal, Hakan and Maurer, Andreas and Rapp, Thomas and Schwarz, Tobias}, booktitle = {Proceedings of the 12th Symposium on Small Satellites for Earth Observation}, editor = {Sandau, Rainer and Brieß, Klaus and Gill, Eberhard}, keywords = {cubesat}, number = 11, pages = {297-301}, publisher = {International Academy of Astronautics (IAA)}, title = {3U satellite bus SONATE for technology demonstration of autonomous payloads,}, volume = 2, year = 2019 }
• On Improving an Embedded Solution for the ASAP Autonomous Planning System. Krainovic, Anselm; Balagurin, Oleksii; Kayal, Hakan; Maurer, Andreas. Vol. IAC 2019 congress proceedings. International Astronautical Federation (IAF), 100 Avenue de Suffren 75015 Paris, France, 2019.
  • [ Abstract ]
  • [ BibTeX ]
  • [ URL ]
  ASAP is an autonomous sensor and planning system developed at the Professorship of Space Technology at the University of Würzburg. The main components have been integrated into the SONATE nanosatellite, which is scheduled for launch in 2019. Equipped with a highspeed optical sensor, ASAP allows the detection and classification of transient events, like meteors entering the Earth’s atmosphere. The planning system is a highly configurable component providing higher autonomy by generating command lists based on the actual satellite state. This allows fast reactions to events, which would not be possible in the classical mission operations. ASAP currently uses FPGA technology. It enables the image processing to work at very high framerates, whereas it limits the available computational resources and frequency of the softcore processor the planning system runs on. Moreover, the scheduling unit of the planning system uses a branch and bound algorithm, whereat each iteration consists of solving a linear program using the Simplex algorithm. Due to the complexity of the algorithm, scheduling is computationally quite expensive. In the scope of this paper we present a possible alternative novel approach to overcome the above limitations by implementing the planning system on a dedicated microcontroller, and more importantly, by developing an improved scheduling algorithm. To do so, we consider sparse matrices as efficient data structures, LU factorizations, revised simplex algorithms and further mathematical concepts. We are closing by evaluating the improvements on the basis of the general concept, as well as typical use case scenarios, and by discussing further possibilities to improve the planning system for an autonomous mission operation.

  @conference{krainovic2019improving, abstract = {ASAP is an autonomous sensor and planning system developed at the Professorship of Space Technology at the University of Würzburg. The main components have been integrated into the SONATE nanosatellite, which is scheduled for launch in 2019. Equipped with a highspeed optical sensor, ASAP allows the detection and classification of transient events, like meteors entering the Earth’s atmosphere. The planning system is a highly configurable component providing higher autonomy by generating command lists based on the actual satellite state. This allows fast reactions to events, which would not be possible in the classical mission operations. ASAP currently uses FPGA technology. It enables the image processing to work at very high framerates, whereas it limits the available computational resources and frequency of the softcore processor the planning system runs on. Moreover, the scheduling unit of the planning system uses a branch and bound algorithm, whereat each iteration consists of solving a linear program using the Simplex algorithm. Due to the complexity of the algorithm, scheduling is computationally quite expensive. In the scope of this paper we present a possible alternative novel approach to overcome the above limitations by implementing the planning system on a dedicated microcontroller, and more importantly, by developing an improved scheduling algorithm. To do so, we consider sparse matrices as efficient data structures, LU factorizations, revised simplex algorithms and further mathematical concepts. We are closing by evaluating the improvements on the basis of the general concept, as well as typical use case scenarios, and by discussing further possibilities to improve the planning system for an autonomous mission operation.}, address = {100 Avenue de Suffren 75015 Paris, France}, author = {Krainovic, Anselm and Balagurin, Oleksii and Kayal, Hakan and Maurer, Andreas}, keywords = {asap}, publisher = {International Astronautical Federation (IAF)}, title = {On Improving an Embedded Solution for the ASAP Autonomous Planning System}, volume = {IAC 2019 congress proceedings}, year = 2019 }
• CMOS Based High Accuracy Miniaturized Digital Sun Sensor with Optimized Error Compensation on SONATE. Baumann, Tom; Balagurin, Oleksii; Kayal, Hakan; Krainovic, Anselm; Luechtrath, Ludwig; Maurer, Andreas. Vol. IAC 2019 Congress Proceedings. International Astronautical Federation (IAF), 100 Avenue de Suffren 75015 Paris, France, 2019.
  • [ Abstract ]
  • [ BibTeX ]
  • [ URL ]
  This paper presents the design, the error compensation methods and satellite integration of a newly developed high accuracy miniature digital two-axis sun sensor, which will be used in the attitude determination and control system of SONATE, a nanosatellite mission developed at the University of Wuerzburg, scheduled for launch in 2019. Nanosatellite missions are putting difficult constraints on its subsystems in terms of size, power consumption and cost, whilst still demanding high performance. The developed sun sensor has been specifically designed to meet these requirements: Low cost is being achieved by the use of commercial grade components, which also provide high computing performance and small sizes. High accuracy is being achieved by compensating errors in the measurements of a CMOS based imaging sensor by the means of an optimized error compensation method, which also takes into account errors caused by optical refraction. The paper also discusses the integration and testing of the hardware in SONATE as well as the calibration techniques used to achieve a high accuracy in-system performance after the AIT phase. We were able to reduce the physical dimensions of the sensor to 25x14x3mm. Measurement results show that the developed sun sensor achieves an angular accuracy of better than 0.4 degrees with a field-of-view greater than +-50 degrees. The optimized error compensation method effectively reduces major error factors and significantly improves accuracy. Radiation and environmental testing have already successfully verified space suitability of the sensor; in orbit testing will validate the design.

  @conference{baumann2019based, abstract = {This paper presents the design, the error compensation methods and satellite integration of a newly developed high accuracy miniature digital two-axis sun sensor, which will be used in the attitude determination and control system of SONATE, a nanosatellite mission developed at the University of Wuerzburg, scheduled for launch in 2019. Nanosatellite missions are putting difficult constraints on its subsystems in terms of size, power consumption and cost, whilst still demanding high performance. The developed sun sensor has been specifically designed to meet these requirements: Low cost is being achieved by the use of commercial grade components, which also provide high computing performance and small sizes. High accuracy is being achieved by compensating errors in the measurements of a CMOS based imaging sensor by the means of an optimized error compensation method, which also takes into account errors caused by optical refraction. The paper also discusses the integration and testing of the hardware in SONATE as well as the calibration techniques used to achieve a high accuracy in-system performance after the AIT phase. We were able to reduce the physical dimensions of the sensor to 25x14x3mm. Measurement results show that the developed sun sensor achieves an angular accuracy of better than 0.4 degrees with a field-of-view greater than +-50 degrees. The optimized error compensation method effectively reduces major error factors and significantly improves accuracy. Radiation and environmental testing have already successfully verified space suitability of the sensor; in orbit testing will validate the design.}, address = {100 Avenue de Suffren 75015 Paris, France}, author = {Baumann, Tom and Balagurin, Oleksii and Kayal, Hakan and Krainovic, Anselm and Luechtrath, Ludwig and Maurer, Andreas}, keywords = {adcs}, publisher = {International Astronautical Federation (IAF)}, title = {CMOS Based High Accuracy Miniaturized Digital Sun Sensor with Optimized Error Compensation on SONATE}, volume = {IAC 2019 Congress Proceedings}, year = 2019 }