Dr.-Ing. Ulrich Römer
- Postdoctoral Researcher
- Office Hours:
by appointment
- Room: 205.2
CS 10.23 - Phone: +49 721 608-46823
- Fax: +49 721 608-46070
- ulrich roemer ∂does-not-exist.kit edu
- www.itm.kit.edu/english/dynamik/Staff_Roemer.php
Postanschrift:
Karlsruher Institut für Technologie
Institut für Technische Mechanik
Teilinstitut Dynamik/Mechatronik
Postfach 6980
76049 KarlsruheHaus- und Lieferanschrift:
KIT-Campus Süd
Institut für Technische Mechanik
Teilinstitut Dynamik/Mechatronik
Geb. 10.23 R 205.2
Kaiserstraße 10
76131 Karlsruhe
Design of bipedal robots with optimized energy efficiency in varying environments
In the development of biped robots, energy efficient locomotion via walking or running is a major research priority. Due to the limited energy storage (battery), energy efficiency significantly determines the walking distance that can be covered. Energy efficiency depends not only on the controller used for stabilizing the motion, but also on the structural design and its mechanical model parameters. Hence, the purpose of this research is to develop and apply a method to systematically optimize the structure of a bipedal robot to maximize energy efficiency in different environments.
In the first step we consider an underactuated robot model which consists of five segments. Its rigid segments are additionally connected by elastic couplings such as torsion springs. Knowing that the robot’s periodic walking or running gaits can be analyzed as limit cycles of the controlled mechanical system, its resonance frequency can be adjusted to match the current step frequency by modifying the elastic couplings. A systematic approach to achieve this matching consists in the simultaneous optimization of the elastic couplings and the controlled motion. Consequently, the robot exploits the mechanical system's natural dynamics instead of wasting energy on its suppression.
Since the optimization of the parameters essentially depends on the conditions of the environment and the gait, the focus is on how the adaptation of the robot to the current operating state can be realized. Unlike the motion, which can be continuously updated by the controller based on the measured state variables, the elastic couplings need to be optimized to achieve the best characteristics by using "compliant smart mechanics" (COSM). Between the stance and swing phases of the robot’s legs, and especially during switching processes of the movement, an optimal (force-displacement and/or force-velocity) characteristic of COSM leads to an overall high energy efficiency for a wide range of walking scenarios.
This project is being carried out jointly by two research groups: The Compliant Systems Group (FG NSYS) from the Ilmenau University of Technology (TU Ilmenau) and the Institute of Engineering Mechanics (ITM) from the Karlsruhe Institute of Technology (KIT). While the team at TU Ilmenau investigates the compliant mechanical systems and their design and implementation, the team at KIT simulates and optimizes bipedal robots with those COSM mechanisms in different environments. It is financially supported by the German Research Foundation (DFG), grant FI 1761/4-1 | ZE 714/16-1.
Project partner: Prof. L. Zentner, M. Zirkel.
Contact: Prof. A. Fidlin, Dr. U. Römer, Y. Luo
Monographs
Römer, U. J.
2019. KIT Scientific Publishing. doi:10.5445/KSP/1000089994
Publications in Journals and Conference Proceedings
Luo, Y.; Römer, U. J.; Zirkel, M.; Zentner, L.; Fidlin, A.
2024. Advances in Nonlinear Dynamics, Volume II – Proceedings of the Third International Nonlinear Dynamics Conference (NODYCON 2023). Editor: Walter Lacarbonara, 73–82, Springer Nature Switzerland. doi:10.1007/978-3-031-50639-0_7
Luo, Y.; Römer, U.; Zirkel, M.; Zentner, L.; Fidlin, A.
2024. Zehnte IFToMM D-A-CH Konferenz 2024 : 05./06. März 2024, Universität Rostock, DuEPublico. doi:10.17185/duepublico/81582
Altoé, P.; Römer, U. J.; Fidlin, A.
2023. 4. VDI-Fachtagung: Schwingungen 2023, Würzburg, 27. und 28. November 2023, 155–170, VDI Verlag. doi:10.51202/9783181024294-155
Stoychev, A. K.; Römer, U. J.
2023. Nonlinear Dynamics, 5963–6000. doi:10.1007/s11071-022-08154-3
Zirkel, M.; Luo, Y.; Römer, U. J.; Fidlin, A.; Zentner, L.
2023. Microactuators, Microsensors and Micromechanisms – MAMM 2022. Ed.: A. Pandey, 46–60, Springer International Publishing. doi:10.1007/978-3-031-20353-4_4
Marquardt, J. E.; Römer, U. J.; Nirschl, H.; Krause, M. J.
2022. Particuology. doi:10.1016/j.partic.2022.12.005
Luo, Y.; Römer, U. J.; Zentner, L.; Fidlin, A.
2022. Advances in Nonlinear Dynamics – Proceedings of the Second International Nonlinear Dynamics Conference (NODYCON 2021), Volume 2. Ed.: W. Lacarbonara, 253–262, Springer International Publishing. doi:10.1007/978-3-030-81166-2_23
Luo, Y.; Zirkel, M.; Römer, U. J.; Zentner, L.; Fidlin, A.
2021. Proceedings in applied mathematics and mechanics, 21 (1), e202100197. doi:10.1002/pamm.202100197
Luo, Y.; Römer, U. J.; Riegraf, S.; Fidlin, A.; Zirkel, M.; Zentner, L.
2021. 3. VDI-Fachtagung: Schwingungen 2021 ; Würzburg, 16. und 17. November 2021, 259–272, VDI Verlag. doi:10.51202/9783181023914-259
Luo, Y.; Römer, U. J.; Fidlin, A.
2021. Proceedings in applied mathematics and mechanics, 20 (1), e202000142. doi:10.1002/pamm.202000142
Zirkel, M.; Luo, Y.; Römer, U. J.; Fidlin, A.; Zentner, L.
2021. Microactuators, Microsensors and Micromechanisms : MAMM 2020. Ed.: L. Zentner, 58–75, Springer International Publishing. doi:10.1007/978-3-030-61652-6_6
Römer, U. J.; Fidlin, A.; Seemann, W.
2020. Mechanism and machine theory, 151, Art.-Nr.: 103906. doi:10.1016/j.mechmachtheory.2020.103906
Kern, D.; Römer, U. J.
2019. 8th GACM Colloquium on Computational Mechanics For Young Scientists From Academia and Industry, August 28th – 30th, 2019, University of Kassel, Germany Proceedings. Ed.: T. Gleim, 211–214, Kassel University Press
Römer, U. J.; Fidlin, A.; Seemann, W.
2018. Mechanism and machine theory, 128, 205–224. doi:10.1016/j.mechmachtheory.2018.05.018
Bauer, F.; Römer, U.; Fidlin, A.; Seemann, W.
2016. Multibody system dynamics, 38 (3), 227–262. doi:10.1007/s11044-016-9509-8
Römer, U. J.; Kuhs, C.; Krause, M. J.; Fidlin, A.
2016. Proceedings of the 2016 IEEE International Conference on Robotics and Automation (ICRA), Stockholm, Sweden 16-21 May 2016, 1374–1381, Institute of Electrical and Electronics Engineers (IEEE). doi:10.1109/ICRA.2016.7487271
Römer, U.; Fidlin, A.; Seemann, W.
2015. Proceedings in applied mathematics and mechanics, 15 (1), 69–70. doi:10.1002/pamm.201510025
Bauer, F.; Römer, U.; Fidlin, A.; Seemann, W.
2015. Nonlinear dynamics, 83 (3), 1275–1301. doi:10.1007/s11071-015-2402-9
Römer, U.; Fidlin, A.
2014. Proceedings in applied mathematics and mechanics, 14 (1), 81–82. doi:10.1002/pamm.201410028
Römer, U.; Bauer, F.; Fidlin, A.
2014. 17th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, CLAWAR 2014, Poznan, Poland; 21 - 23 July, 2014, 409–416, World Scientific Publishing. doi:10.1142/9789814623353_0048
Talks at Conferences and Colloquia
Stoychev, A. K.; Römer, U. J.
2023, June 20. 3. International Nonlinear Dynamics Conference (NODYCON 2023), Rome, Italy, June 18–22, 2023
Römer, U. J.
2023, May 30. 93rd Annual Meeting of the International Association of Applied Mathematics and Mechanics (GAMM 2023), Dresden, Germany, May 30–June 2, 2023
Römer, U. J.
2021, August 24. 25th International Congress of Theoretical and Applied Mechanics (ICTAM 2021), Online, August 22–27, 2021
Römer, U. J.; Seemann, W.; Fidlin, A.
2020. 6. IFToMM D-A-CH Konferenz 2020 : 27./28. Februar 2020, Campus Technik Lienz. doi:10.17185/duepublico/71212
Römer, U. J.; Fidlin, A.; Seemann, W.
2018. 89. Jahrestagung der Gesellschaft für angewandte Mathematik und Mechanik (GAMM 2018), Munich, Germany, March 19–23, 2018
Römer, U. J.; Fidlin, A.
2017. 9th European Nonlinear Oscillations Conference (ENOC 2017), Budapest, Hungary, June 25–30, 2017
Römer, U. J.; Fidlin, A.; Seemann, W.
2016. 87. Jahrestagung der Gesellschaft für angewandte Mathematik und Mechanik (GAMM 2016), Brunswick, Germany, March 7–11, 2016
Römer, U. J.; Fidlin, A.
2016. Dynamic Walking (2016), Holly, MI, USA, June 4–7, 2016
Römer, U.; Bauer, F.; Seemann, W.; Fidlin, A.
2014, May 14. 4th French-German-Japanese Conference on Humanoid and Legged Robots (2014), Heidelberg, Germany, May 12–14, 2014
| Title | Type | Date |
|---|---|---|
| Energy Efficiency Optimization of a Two-legged Robot | Thesis (B.Sc. or M.Sc.) | as of now |
| Design of a Two-legged Robot Prototype | Thesis (B.Sc. or M.Sc.) | as of now |