Structured contact force optimization for kino-dynamic motion generation

Alexander Herzog, Stefan Schaal, Ludovic Righetti

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Optimal control approaches in combination with trajectory optimization have recently proven to be a promising control strategy for legged robots. Computationally efficient and robust algorithms were derived using simplified models of the contact interaction between robot and environment such as the linear inverted pendulum model (LIPM). However, as humanoid robots enter more complex environments, less restrictive models become increasingly important. As we leave the regime of linear models, we need to build dedicated solvers that can compute interaction forces together with consistent kinematic plans for the whole-body. In this paper, we address the problem of planning robot motion and interaction forces for legged robots given predefined contact surfaces. The motion generation process is decomposed into two alternating parts computing force and motion plans in coherence. We focus on the properties of the momentum computation leading to sparse optimal control formulations to be exploited by a dedicated solver. In our experiments, we demonstrate that our motion generation algorithm computes consistent contact forces and joint trajectories for our humanoid robot. We also demonstrate the favorable time complexity due to our formulation and composition of the momentum equations.

Original languageEnglish (US)
Title of host publicationIROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages2703-2710
Number of pages8
Volume2016-November
ISBN (Electronic)9781509037629
DOIs
StatePublished - Nov 28 2016
Event2016 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2016 - Daejeon, Korea, Republic of
Duration: Oct 9 2016Oct 14 2016

Other

Other2016 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2016
CountryKorea, Republic of
CityDaejeon
Period10/9/1610/14/16

Fingerprint

Robots
Momentum
Trajectories
Pendulums
Kinematics
Planning
Chemical analysis
Experiments

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Software
  • Computer Vision and Pattern Recognition
  • Computer Science Applications

Cite this

Herzog, A., Schaal, S., & Righetti, L. (2016). Structured contact force optimization for kino-dynamic motion generation. In IROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (Vol. 2016-November, pp. 2703-2710). [7759420] Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/IROS.2016.7759420

Structured contact force optimization for kino-dynamic motion generation. / Herzog, Alexander; Schaal, Stefan; Righetti, Ludovic.

IROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems. Vol. 2016-November Institute of Electrical and Electronics Engineers Inc., 2016. p. 2703-2710 7759420.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Herzog, A, Schaal, S & Righetti, L 2016, Structured contact force optimization for kino-dynamic motion generation. in IROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems. vol. 2016-November, 7759420, Institute of Electrical and Electronics Engineers Inc., pp. 2703-2710, 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2016, Daejeon, Korea, Republic of, 10/9/16. https://doi.org/10.1109/IROS.2016.7759420
Herzog A, Schaal S, Righetti L. Structured contact force optimization for kino-dynamic motion generation. In IROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems. Vol. 2016-November. Institute of Electrical and Electronics Engineers Inc. 2016. p. 2703-2710. 7759420 https://doi.org/10.1109/IROS.2016.7759420
Herzog, Alexander ; Schaal, Stefan ; Righetti, Ludovic. / Structured contact force optimization for kino-dynamic motion generation. IROS 2016 - 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems. Vol. 2016-November Institute of Electrical and Electronics Engineers Inc., 2016. pp. 2703-2710
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