@inproceedings{RensFerreinPoel2008, author = {Rens, Gavin and Ferrein, Alexander and Poel, Etienne van der}, title = {Extending DTGolog to deal with POMD-Ps}, series = {Proceedings of the Nineteenth Annual Symposium of the Pattern Recognition Association of South Africa (PRASA 2008)}, booktitle = {Proceedings of the Nineteenth Annual Symposium of the Pattern Recognition Association of South Africa (PRASA 2008)}, organization = {Pattern Recognition Association of South Africa}, pages = {49 -- 54}, year = {2008}, language = {en} } @inproceedings{HeringUlberTippkoetter2016, author = {Hering, T. and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Development of a screening system for antimicrobial surfaces}, series = {New frontiers of biotech-processes (Himmelfahrtstagung) : 02-04 May 2016, Rhein-Mosel-Halle, Koblenz/Germany}, booktitle = {New frontiers of biotech-processes (Himmelfahrtstagung) : 02-04 May 2016, Rhein-Mosel-Halle, Koblenz/Germany}, publisher = {DECHEMA}, address = {Frankfurt am Main}, pages = {129}, year = {2016}, language = {en} } @inproceedings{AlexopoulosHoffschmidtRauetal.2012, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard and Rau, Christoph and Sattler, Johannes, Christoph}, title = {Simulation of hybrid solar tower power plants}, series = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, booktitle = {30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Solar Energy Society}, pages = {4044 -- 4050}, year = {2012}, language = {en} } @inproceedings{StaatBallmann1989, author = {Staat, Manfred and Ballmann, J.}, title = {Fundamental aspects of numerical methods for the propagation of multi-dimensional nonlinear waves in solids}, series = {Nonlinear hyperbolic equations : theory, computations methods, and applications ; proceedings of the 2nd International Conference on Nonlinear Hyperbolic Problems, Aachen}, booktitle = {Nonlinear hyperbolic equations : theory, computations methods, and applications ; proceedings of the 2nd International Conference on Nonlinear Hyperbolic Problems, Aachen}, pages = {574 -- 588}, year = {1989}, abstract = {The nonlinear scalar constitutive equations of gases lead to a change in sound speed from point to point as would be found in linear inhomogeneous (and time dependent) media. The nonlinear tensor constitutive equations of solids introduce the additional local effect of solution dependent anisotropy. The speed of a wave passing through a point changes with propagation direction and its rays are inclined to the front. It is an open question whether the widely used operator splitting techniques achieve a dimensional splitting with physically reasonable results for these multi-dimensional problems. May be this is the main reason why the theoretical and numerical investigations of multi-dimensional wave propagation in nonlinear solids are so far behind gas dynamics. We hope to promote the subject a little by a discussion of some fundamental aspects of the solution of the equations of nonlinear elastodynamics. We use methods of characteristics because they only integrate mathematically exact equations which have a direct physical interpretation.}, subject = {Nichtlineare Welle}, language = {en} } @inproceedings{ViehmannLimpertHofmannetal.2023, author = {Viehmann, Tarik and Limpert, Nicolas and Hofmann, Till and Henning, Mike and Ferrein, Alexander and Lakemeyer, Gerhard}, title = {Winning the RoboCup logistics league with visual servoing and centralized goal reasoning}, series = {RoboCup 2022: Robot World Cup XXV}, booktitle = {RoboCup 2022: Robot World Cup XXV}, editor = {Eguchi, Amy and Lau, Nuno and Paetzel-Pr{\"u}smann, Maike and Wanichanon, Thanapat}, publisher = {Springer}, address = {Cham}, isbn = {978-3-031-28468-7 (Print)}, doi = {https://doi.org/10.1007/978-3-031-28469-4_25}, pages = {300 -- 312}, year = {2023}, abstract = {The RoboCup Logistics League (RCLL) is a robotics competition in a production logistics scenario in the context of a Smart Factory. In the competition, a team of three robots needs to assemble products to fulfill various orders that are requested online during the game. This year, the Carologistics team was able to win the competition with a new approach to multi-agent coordination as well as significant changes to the robot's perception unit and a pragmatic network setup using the cellular network instead of WiFi. In this paper, we describe the major components of our approach with a focus on the changes compared to the last physical competition in 2019.}, language = {en} } @inproceedings{TranMatthiesStavroulakisetal.2018, author = {Tran, Ngoc Trinh and Matthies, Hermann G. and Stavroulakis, Georgios Eleftherios and Staat, Manfred}, title = {Direct plastic structural design by chance constrained programming}, series = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, booktitle = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, pages = {12 Seiten}, year = {2018}, abstract = {We propose a stochastic programming method to analyse limit and shakedown of structures under random strength with lognormal distribution. In this investigation a dual chance constrained programming algorithm is developed to calculate simultaneously both the upper and lower bounds of the plastic collapse limit or the shakedown limit. The edge-based smoothed finite element method (ES-FEM) using three-node linear triangular elements is used.}, language = {en} } @inproceedings{FingerBraunBil2018, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Case studies in initial sizing for hybrid-electric general aviation aircraft}, series = {2018 AIAA/IEEE Electric Aircraft Technologies Symposium, Cincinnati, Ohio}, booktitle = {2018 AIAA/IEEE Electric Aircraft Technologies Symposium, Cincinnati, Ohio}, doi = {10.2514/6.2018-5005}, year = {2018}, language = {en} } @inproceedings{DachwaldBaturkinCoverstoneetal.2005, author = {Dachwald, Bernd and Baturkin, Volodymyr and Coverstone, Victoria and Diedrich, Ben and Garbe, Gregory and G{\"o}rlich, Marianne and Leipold, Manfred and Lura, Franz and Macdonald, Malcolm and McInnes, Colin and Mengali, Giovanni and Quarta, Alessandro and Rios-Reyes, Leonel and Scheeres, Daniel J. and Seboldt, Wolfgang and Wie, Bong}, title = {Potential effects of optical solar sail degredation on trajectory design}, series = {AAS/AIAA Astrodynamics Specialist}, booktitle = {AAS/AIAA Astrodynamics Specialist}, pages = {1 -- 23}, year = {2005}, abstract = {The optical properties of the thin metalized polymer films that are projected for solar sails are assumed to be affected by the erosive effects of the space environment. Their degradation behavior in the real space environment, however, is to a considerable degree indefinite, because initial ground test results are controversial and relevant inspace tests have not been made so far. The standard optical solar sail models that are currently used for trajectory design do not take optical degradation into account, hence its potential effects on trajectory design have not been investigated so far. Nevertheless, optical degradation is important for high-fidelity solar sail mission design, because it decreases both the magnitude of the solar radiation pressure force acting on the sail and also the sail control authority. Therefore, we propose a simple parametric optical solar sail degradation model that describes the variation of the sail film's optical coefficients with time, depending on the sail film's environmental history, i.e., the radiation dose. The primary intention of our model is not to describe the exact behavior of specific film-coating combinations in the real space environment, but to provide a more general parametric framework for describing the general optical degradation behavior of solar sails. Using our model, the effects of different optical degradation behaviors on trajectory design are investigated for various exemplary missions.}, language = {en} } @inproceedings{Staat2012, author = {Staat, Manfred}, title = {Limit and shakedown analysis under uncertainty}, series = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)}, booktitle = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)}, pages = {837 -- 861}, year = {2012}, language = {de} } @inproceedings{NikolovskiLimpertNessauetal.2023, author = {Nikolovski, Gjorgji and Limpert, Nicolas and Nessau, Hendrik and Reke, Michael and Ferrein, Alexander}, title = {Model-predictive control with parallelised optimisation for the navigation of autonomous mining vehicles}, series = {2023 IEEE Intelligent Vehicles Symposium (IV)}, booktitle = {2023 IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, isbn = {979-8-3503-4691-6 (Online)}, doi = {10.1109/IV55152.2023.10186806}, pages = {6 Seiten}, year = {2023}, abstract = {The work in modern open-pit and underground mines requires the transportation of large amounts of resources between fixed points. The navigation to these fixed points is a repetitive task that can be automated. The challenge in automating the navigation of vehicles commonly used in mines is the systemic properties of such vehicles. Many mining vehicles, such as the one we have used in the research for this paper, use steering systems with an articulated joint bending the vehicle's drive axis to change its course and a hydraulic drive system to actuate axial drive components or the movements of tippers if available. To address the difficulties of controlling such a vehicle, we present a model-predictive approach for controlling the vehicle. While the control optimisation based on a parallel error minimisation of the predicted state has already been established in the past, we provide insight into the design and implementation of an MPC for an articulated mining vehicle and show the results of real-world experiments in an open-pit mine environment.}, language = {en} }