@inproceedings{WeissAbanteribaEsch2007,
  author    = {Weiss, Alexander and Abanteriba, Sylvester and Esch, Thomas},
  title     = {Investigation of Flow Separation Inside a Conical Rocket Nozzle With the Aid of an Annular Cross Flow},
  series = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B},
  booktitle = {Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B},
  publisher = {American Society of Mechanical Engineers (ASME)},
  address   = {New York},
  isbn      = {0-7918-4288-6},
  doi       = {10.1115/FEDSM2007-37387},
  pages     = {1861 -- 1871},
  year      = {2007},
  abstract  = {Flow separation is a phenomenon that occurs in all kinds of supersonic nozzles sometimes during run-up and shut-down operations. Especially in expansion nozzles of rocket engines with large area ratio, flow separation can trigger strong side loads that can damage the structure of the nozzle. The investigation presented in this paper seeks to establish measures that may be applied to alter the point of flow separation. In order to achieve this, a supersonic nozzle was placed at the exit plane of the conical nozzle. This resulted in the generation of cross flow surrounding the core jet flow from the conical nozzle. Due to the entrainment of the gas stream from the conical nozzle the pressure in its exit plane was found to be lower than that of the ambient. A Cold gas instead of hot combustion gases was used as the working fluid. A mathematical simulation of the concept was validated by experiment. Measurements confirmed the simulation results that due to the introduction of a second nozzle the pressure in the separated region of the conical nozzle was significantly reduced. It was also established that the boundary layer separation inside the conical nozzle was delayed thus allowing an increased degree of overexpansion. The condition established by the pressure measurements was also demonstrated qualitatively using transparent nozzle configurations.},
  language  = {en}
}
@inproceedings{HuthElsenHartwigetal.2006,
  author    = {Huth, Thomas and Elsen, Olaf and Hartwig, Christoph and Esch, Thomas},
  title     = {Innovative modular valve trains for 2015 - logistic benefits by EMVT},
  series = {IFAC Proceedings Volumes, Volume 39, Issue 3},
  booktitle = {IFAC Proceedings Volumes, Volume 39, Issue 3},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.3182/20060517-3-FR-2903.00172},
  pages     = {315 -- 320},
  year      = {2006},
  abstract  = {In this paper the way to a 5-day-car with respect to a modular valve train systems for spark ignited combustion engines is shown. The necessary product diversity is shift from mechanical or physical components to software components. Therefore, significant improvements of logistic indicators are expected and shown. The working principle of a camless cylinder head with respect to an electromagnetical valve train (EMVT) is explained and it is demonstrated that shifting physical diversity to software is feasible. The future design of combustion engine systems including customisation can be supported by a set of assistance tools which is shown exemplary.},
  language  = {en}
}
@inproceedings{FunkeBeckmannStefanetal.2023,
  author    = {Funke, Harald and Beckmann, Nils and Stefan, Lukas and Keinz, Jan},
  title     = {Hydrogen combustor integration study for a medium range aircraft engine using the dry-low NOx "Micromix" combustion principle},
  series = {Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine.},
  booktitle = {Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine.},
  publisher = {ASME},
  address   = {New York},
  isbn      = {978-0-7918-8693-9},
  doi       = {10.1115/GT2023-102370},
  pages     = {12 Seiten},
  year      = {2023},
  abstract  = {The feasibility study presents results of a hydrogen combustor integration for a Medium-Range aircraft engine using the Dry-Low-NOₓ Micromix combustion principle. Based on a simplified Airbus A320-type flight mission, a thermodynamic performance model of a kerosene and a hydrogen-powered V2530-A5 engine is used to derive the thermodynamic combustor boundary conditions. A new combustor design using the Dry-Low NOx Micromix principle is investigated by slice model CFD simulations of a single Micromix injector for design and off-design operation of the engine. Combustion characteristics show typical Micromix flame shapes and good combustion efficiencies for all flight mission operating points. Nitric oxide emissions are significant below ICAO CAEP/8 limits. For comparison of the Emission Index (EI) for NOₓ emissions between kerosene and hydrogen operation, an energy (kerosene) equivalent Emission Index is used. A full 15° sector model CFD simulation of the combustion chamber with multiple Micromix injectors including inflow homogenization and dilution and cooling air flows investigates the combustor integration effects, resulting NOₓ emission and radial temperature distributions at the combustor outlet. The results show that the integration of a Micromix hydrogen combustor in actual aircraft engines is feasible and offers, besides CO₂ free combustion, a significant reduction of NOₓ emissions compared to kerosene operation.},
  language  = {en}
}
@inproceedings{GehlerOberBloebaumDachwald2009,
  author    = {Gehler, M. and Ober-Bl{\"o}baum, S. and Dachwald, Bernd},
  title     = {Application of discrete mechanics and optimal control to spacecraft in non-keplerian motion around small solar system bodies},
  series = {Procceedings of the 60th International Astronautical Congress},
  booktitle = {Procceedings of the 60th International Astronautical Congress},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {978-161567908-9},
  pages     = {1360 -- 1371},
  year      = {2009},
  abstract  = {Prolonged operations close to small solar system bodies require a sophisticated control logic to minimize propellant mass and maximize operational efficiency. A control logic based on Discrete Mechanics and Optimal Control (DMOC) is proposed and applied to both conventionally propelled and solar sail spacecraft operating at an arbitrarily shaped asteroid in the class of Itokawa. As an example, stand-off inertial hovering is considered, recently identified as a challenging part of the Marco Polo mission. The approach is easily extended to stand-off orbits. We show that DMOC is applicable to spacecraft control at small objects, in particular with regard to the fact that the changes in gravity are exploited by the algorithm to optimally control the spacecraft position. Furthermore, we provide some remarks on promising developments.},
  language  = {en}
}
@inproceedings{DachwaldWurm2009,
  author    = {Dachwald, Bernd and Wurm, P.},
  title     = {Design concept and modeling of an advanced solar photon thruster},
  series = {Advances in the Astronautical Sciences},
  booktitle = {Advances in the Astronautical Sciences},
  publisher = {American Astronautical Society},
  address   = {San Diego, Calif.},
  isbn      = {978-087703554-1},
  issn      = {00653438},
  pages     = {723 -- 740},
  year      = {2009},
  abstract  = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), holds the potential of providing significant performance advantages over the flat solar sail. Previous SPT design concepts, however, do not consider shadowing effects and multiple reflections of highly concentrated solar radiation that would inevitably destroy the gossamer sail film. In this paper, we propose a novel advanced SPT (ASPT) design concept that does not suffer from these oversimplifications. We present the equations that describe the thrust force acting on such a sail system and compare its performance with respect to the conventional flat solar sail.},
  language  = {en}
}
@inproceedings{DachwaldWurm2009,
  author    = {Dachwald, Bernd and Wurm, P.},
  title     = {Mission analysis for an advanced solar photon thruster},
  series = {60th International Astronautical Congress 2009, IAC 2009},
  volume    = {8},
  booktitle = {60th International Astronautical Congress 2009, IAC 2009},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {978-161567908-9},
  pages     = {6838 -- 6851},
  year      = {2009},
  abstract  = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a solar sail design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT). This model does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. We present the equations that describe the force, which acts on the ASPT. After a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: An Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large orbital eccentricity change is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2mm/s2. Our results show that a SPT is not superior to the flat solar sail unless very idealistic assumptions are made.},
  language  = {en}
}
@inproceedings{MulsowHuelsenGuetzlaffetal.2023,
  author    = {Mulsow, Niklas A. and H{\"u}lsen, Benjamin and G{\"u}tzlaff, Joel and Spies, Leon and Bresser, Andreas and Dabrowski, Adam and Czupalla, Markus and Kirchner, Frank},
  title     = {Concept and design of an autonomous micro rover for long term lunar exploration},
  series = {Proceedings of the 74th International Astronautical Congress},
  booktitle = {Proceedings of the 74th International Astronautical Congress},
  publisher = {dfki},
  address   = {Saarbr{\"u}cken},
  pages     = {13 Seiten},
  year      = {2023},
  abstract  = {Research on robotic lunar exploration has seen a broad revival, especially since the Google Lunar X-Prize increasingly brought private endeavors into play. This development is supported by national agencies with the aim of enabling long-term lunar infrastructure for in-situ operations and the establishment of a moon village. One challenge for effective exploration missions is developing a compact and lightweight robotic rover to reduce launch costs and open the possibility for secondary payload options. Existing micro rovers for exploration missions are clearly limited by their design for one day of sunlight and their low level of autonomy. For expanding the potential mission applications and range of use, an extension of lifetime could be reached by surviving the lunar night and providing a higher level of autonomy. To address this objective, the paper presents a system design concept for a lightweight micro rover with long-term mission duration capabilities, derived from a multi-day lunar mission scenario at equatorial regions. Technical solution approaches are described, analyzed, and evaluated, with emphasis put on the harmonization of hardware selection due to a strictly limited budget in dimensions and power.},
  language  = {en}
}
@inproceedings{HuelsenMulsowDabrowskietal.2023,
  author    = {H{\"u}lsen, Benjamin and Mulsow, Niklas A. and Dabrowski, Adam and Brinkmann, Wiebke and G{\"u}tzlaff, Joel and Spies, Leon and Czupalla, Markus and Kirchner, Frank},
  title     = {Towards an autonomous micro rover with night survivability for lunar exploration},
  series = {Proceedings of the 74th International Astronautical Congress},
  booktitle = {Proceedings of the 74th International Astronautical Congress},
  publisher = {dfki},
  pages     = {12 Seiten},
  year      = {2023},
  abstract  = {In Europe, efforts are underway to develop key technologies that can be used to explore the Moon and to exploit the resources available. This includes technologies for in-situ resource utilization (ISRU), facilitating the possibility of a future Moon Village. The Moon is the next step for humans and robots to exploit the use of available resources for longer term missions, but also for further exploration of the solar system. A challenge for effective exploration missions is to achieve a compact and lightweight robot to reduce launch costs and open up the possibility of secondary payload options. Current micro rover concepts are primarily designed to last for one day of solar illumination and show a low level of autonomy. Extending the lifetime of the system by enabling survival of the lunar night and implementing a high level of autonomy will significantly increase potential mission applications and the operational range. As a reference mission, the deployment of a micro rover in the equatorial region of the Moon is being considered. An overview of mission parameters and a detailed example mission sequence is given in this paper. The mission parameters are based on an in-depth study of current space agency roadmaps, scientific goals, and upcoming flight opportunities. Furthermore, concepts of the ongoing international micro rover developments are analyzed along with technology solutions identified for survival of lunar nights and a high system autonomy. The results provide a basis of a concise requirements set-up to allow dedicated system developments and qualification measures in the future.},
  language  = {en}
}
@inproceedings{WildCzupallaFoerstner2021,
  author    = {Wild, Dominik and Czupalla, Markus and F{\"o}rstner, Roger},
  title     = {Modeling, prediction and test of additive manufactured integral structures with embedded lattice and phase change material applying Infused Thermal Solutions (ITS)},
  series = {ICES104: Advances in Thermal Control Technology},
  booktitle = {ICES104: Advances in Thermal Control Technology},
  publisher = {Texas Tech University},
  address   = {Lubbock, Tex.},
  pages     = {12 Seiten},
  year      = {2021},
  abstract  = {Infused Thermal Solutions (ITS) introduces a method for passive thermal control to stabilize structural components thermally without active heating and cooling systems, but with phase change material (PCM) for thermal energy storage (TES), in combination with lattice - both embedded in additive manufactured functional structures. In this ITS follow-on paper a thermal model approach and associated predictions are presented, related on the ITS functional breadboards developed at FH Aachen. Predictive TES by PCM is provided by a specially developed ITS PCM subroutine, which is applicable in ESATAN. The subroutine is based on the latent heat storage (LHS) method to numerically embed thermo-physical PCM behavior. Furthermore, a modeling approach is introduced to numerically consider the virtual PCM/lattice nodes within the macro-encapsulated PCM voids of the double wall ITS design. Related on these virtual nodes, in-plane and out-of-plane conductive links are defined. The recent additive manufactured ITS breadboard series are thermally cycled in the thermal vacuum chamber, both with and without embedded PCM. Related on breadboard hardware tests, measurement results are compared with predictions and are subsequently correlated. The results of specific simulations and measurements are presented. Recent predictive results of star tracker analyses are also presented in ICES-2021-106, based on this ITS PCM subroutine.},
  language  = {en}
}
@inproceedings{KohlbergerWildKasperetal.2021,
  author    = {Kohlberger, David-Sharif and Wild, Dominik and Kasper, Stefan and Czupalla, Markus},
  title     = {Modeling and analyses of a thermal passively stabilized LEO/GEO star tracker with embedded phase change material applying the Infused Thermal Solutions (ITS) method},
  series = {ICES202: Satellite, Payload, and Instrument Thermal Control},
  booktitle = {ICES202: Satellite, Payload, and Instrument Thermal Control},
  publisher = {Texas Tech University},
  address   = {Lubbock, Tex.},
  pages     = {12 Seiten},
  year      = {2021},
  abstract  = {Phase change materials offer a way of storing excess heat and releasing it when it is needed. They can be utilized as a method to control thermal behavior without the need for additional energy. This work focuses on exploring the potential of using phase change materials to passively control the thermal behavior of a star tracker by infusing it with a fitting phase change material. Based on the numerical model of the star trackers thermal behavior using ESATAN-TMS without implemented phase change material, a fitting phase change material for selected orbits is chosen and implemented in the thermal model. The altered thermal behavior of the numerical model after the implementation is analyzed for different amounts of the chosen phase change materials using an ESATAN-based subroutine developed by the FH Aachen. The PCM-modelling-subroutine is explained in the paper ICES-2021-110. The results show that an increasing amount of phase change material increasingly damps temperature oscillations. Using an integral part structure some of the mass increase can be compensated.},
  language  = {en}
}
@inproceedings{VeettilRakshitSchopenetal.2022,
  author    = {Veettil, Yadu Krishna Morassery and Rakshit, Shantam and Schopen, Oliver and Kemper, Hans and Esch, Thomas and Shabani, Bahman},
  title     = {Automated Control System Strategies to Ensure Safety of PEM Fuel Cells Using Kalman Filters},
  series = {Proceedings of the 7th International Conference and Exhibition on Sustainable Energy and Advanced Materials (ICE-SEAM 2021), Melaka, Malaysia},
  booktitle = {Proceedings of the 7th International Conference and Exhibition on Sustainable Energy and Advanced Materials (ICE-SEAM 2021), Melaka, Malaysia},
  editor    = {Bin Abdollah, Mohd Fadzli and Amiruddin, Hilmi and Singh, Amrik Singh Phuman and Munir, Fudhail Abdul and Ibrahim, Asriana},
  publisher = {Springer Nature},
  address   = {Singapore},
  isbn      = {978-981-19-3178-9},
  issn      = {2195-4356},
  doi       = {10.1007/978-981-19-3179-6_55},
  pages     = {296 -- 299},
  year      = {2022},
  abstract  = {Having well-defined control strategies for fuel cells, that can efficiently detect errors and take corrective action is critically important for safety in all applications, and especially so in aviation. The algorithms not only ensure operator safety by monitoring the fuel cell and connected components, but also contribute to extending the health of the fuel cell, its durability and safe operation over its lifetime. While sensors are used to provide peripheral data surrounding the fuel cell, the internal states of the fuel cell cannot be directly measured. To overcome this restriction, Kalman Filter has been implemented as an internal state observer. Other safety conditions are evaluated using real-time data from every connected sensor and corrective actions automatically take place to ensure safety. The algorithms discussed in this paper have been validated thorough Model-in-the-Loop (MiL) tests as well as practical validation at a dedicated test bench.},
  language  = {en}
}
@inproceedings{SchopenKemperEsch2021,
  author    = {Schopen, Oliver and Kemper, Hans and Esch, Thomas},
  title     = {Development of a comparison methodology and evaluation matrix for electrically driven compressors in ICE and FC},
  series = {Proceedings of the 1st UNITED - Southeast Asia Automotive Interest Group (SAIG) International Conference},
  booktitle = {Proceedings of the 1st UNITED - Southeast Asia Automotive Interest Group (SAIG) International Conference},
  publisher = {FH Joanneum},
  address   = {Graz},
  isbn      = {978-3-902103-94-9},
  pages     = {45 -- 46},
  year      = {2021},
  abstract  = {In addition to electromobility and alternative drive systems, a focus is set on electrically driven compressors (EDC), with a high potential for increasing the efficiency of internal combustion engines (ICE) and fuel cells [01]. The primary objective is to increase the ICE torque, provided independently of the ICE speed by compressing the intake air and consequently the ICE filling level supported by the compressor. For operation independent from the ICE speed, the EDC compressor is decoupled from the turbine by using an electric compressor motor (CM) instead of the turbine. ICE performances can be increased by the use of EDC where individual compressor parameters are adapted to the respective application area [02] [03]. This task contains great challenges, increased by demands with regard to pollutant reduction while maintaining constant performance and reduced fuel consumption. The FH-Aachen is equipped with an EDC test bench which enables EDC-investigations in various configurations and operating modes. Characteristic properties of different compressors can be determined, which build the basis for a comparison methodology. Subject of this project is the development of a comparison methodology for EDC with an associated evaluation method and a defined overall evaluation method. For the application of this comparison methodology, corresponding series of measurements are carried out on the EDC test bench using an appropriate test device.},
  language  = {en}
}
@inproceedings{SchopenShabaniEschetal.2022,
  author    = {Schopen, Oliver and Shabani, Bahman and Esch, Thomas and Kemper, Hans and Shah, Neel},
  title     = {Quantitative evaluation of health management designs for fuel cell systems in transport vehicles},
  series = {2nd UNITED-SAIG International Conference Proceedings},
  booktitle = {2nd UNITED-SAIG International Conference Proceedings},
  editor    = {Rahim, S.A. and As'arry, A. and Zuhri, M.Y.M. and Harmin, M.Y. and Rezali, K.A.M. and Hairuddin, A.A.},
  pages     = {1 -- 3},
  year      = {2022},
  abstract  = {Focusing on transport vehicles, mainly with regard to aviation applications, this paper presents compilation and subsequent quantitative evaluation of methods aimed at building an optimum integrated health management solution for fuel cell systems. The methods are divided into two different main types and compiled in a related scheme. Furthermore, different methods are analysed and evaluated based on parameters specific to the aviation context of this study. Finally, the most suitable method for use in fuel cell health management systems is identified and its performance and suitability is quantified.},
  language  = {en}
}
@inproceedings{StarkRiepingEsch2023,
  author    = {Stark, Ralf and Rieping, Carla and Esch, Thomas},
  title     = {The impact of guide tubes on flow separation in rocket nozzles},
  series = {Aerospace Europe Conference 2023 - 10th EUCASS - 9th CEAS},
  booktitle = {Aerospace Europe Conference 2023 - 10th EUCASS - 9th CEAS},
  pages     = {8 Seiten},
  year      = {2023},
  abstract  = {Rocket engine test facilities and launch pads are typically equipped with a guide tube. Its purpose is to ensure the controlled and safe routing of the hot exhaust gases. In addition, the guide tube induces a suction that effects the nozzle flow, namely the flow separation during transient start-up and shut-down of the engine. A cold flow subscale nozzle in combination with a set of guide tubes was studied experimentally to determine the main influencing parameters.},
  language  = {en}
}
@inproceedings{BergmannGraebenerWildetal.2019,
  author    = {Bergmann, Kevin and Gr{\"a}bener, Josefine and Wild, Dominik and Ulfers, H. and Czupalla, Markus},
  title     = {Study on thermal stabilization of a GEO-stationary telescope baffling system by integral application of phase change material},
  series = {International Conference on Environmental Systems},
  booktitle = {International Conference on Environmental Systems},
  pages     = {1 -- 14},
  year      = {2019},
  abstract  = {The utilization of phase change material (PCM) for latent heat storage and thermal control of spacecraft has been demonstrated in the past in few missions only. One limiting factor was the fact that all concepts developed so far envisioned the PCM to be applied as an additional capacitor, encapsulated in its own housing, leading to mass, efficiency and accommodation challenges. Recently, the application of PCM within the scan cavity of a GEOS type satellite has been suggested, in order to tackle thermal issues due to direct sun intrusion (Choi, M., 2014). However, the application of PCM in such complex mechanical structures is extremely challenging. A new concept to tackle this issue is currently under development at the FH Aachen University of Applied Sciences. The concept "Infused Thermal Solutions (ITS)" is based on the idea to 3D print metallic structures in their regular functional shape, but double walled with internal lattice support structures, allowing the infusion of a PCM layer directly into the voids and eliminating the need for additional parts and interfaces. Together with OHB System, FH Aachen theoretically studied the application of this technology to the Meteosat Third Generation (MTG) Infra-Red Sounder (IRS) instrument. The study focuses on the scan cavity and entrance baffling assembly (EBA) of the IRS. It consists of thermal analyses, 3D-redesign and bread boarding of a scaled and PCM infused EBA version. In the thermal design of the alternative EBA, PCM was applied directly into the EBA, simulating the worst hot case sun intrusion of the mission. By applying 4kg of PCM (to a 60kg baffle) the EBA temperature excursions during sun intrusion were limited from 140K to 30K, leading to a significant thermo-opto-elastic performance gain. This paper introduces the ITS concept development status.},
  language  = {en}
}
@inproceedings{MayntzKeimerDahmannetal.2022,
  author    = {Mayntz, Joscha and Keimer, Jona and Dahmann, Peter and Hille, Sebastian and Stumpf, Eike and Fisher, Alex and Dorrington, Graham},
  title     = {Electrical Drive and Regeneration in General Aviation Flight with Propellers},
  series = {Deutscher Luft- und Raumfahrtkongress 2020},
  booktitle = {Deutscher Luft- und Raumfahrtkongress 2020},
  publisher = {DGLR},
  address   = {Bonn},
  doi       = {10.25967/530100},
  pages     = {8 Seiten},
  year      = {2022},
  abstract  = {Electric flight has the potential for a more sustainable and energy-saving way of aviation compared to fossil fuel aviation. The electric motor can be used as a generator inflight to regenerate energy during descent. Three different approaches to regenerating with electric propeller powertrains are proposed in this paper. The powertrain is to be set up in a wind tunnel to determine the propeller efficiency in both working modes as well as the noise emissions. Furthermore, the planned flight tests are discussed. In preparation for these tests, a yaw stability analysis is performed with the result that the aeroplane is controllable during flight and in the most critical failure case. The paper shows the potential for inflight regeneration and addresses the research gaps in the dual role of electric powertrains for propulsion and regeneration of general aviation aircraft.},
  language  = {en}
}
@inproceedings{SchildtMarzoccaBraunetal.2019,
  author    = {Schildt, Philipp and Marzocca, Pier and Braun, Carsten and Dahmann, Peter and Keimer, Jona},
  title     = {Effects of atmospheric excitation on vibration based condition monitoring methods for hybrid-electric aircraft propulsion systems},
  series = {AIAC 2018: 18th Australian International Aerospace Congress: HUMS - 11th Defence Science and Technology (DST) International Conference on Health and Usage Monitoring (HUMS 2019): ISSFD - 27th International Symposium on Space Flight Dynamics (ISSFD)},
  booktitle = {AIAC 2018: 18th Australian International Aerospace Congress: HUMS - 11th Defence Science and Technology (DST) International Conference on Health and Usage Monitoring (HUMS 2019): ISSFD - 27th International Symposium on Space Flight Dynamics (ISSFD)},
  isbn      = {9781925627213},
  pages     = {923 -- 928},
  year      = {2019},
  language  = {en}
}