Autonomous Robots

, Volume 33, Issue 4, pp 361–379 | Cite as

Reinforcement learning to adjust parametrized motor primitives to new situations

  • Jens KoberEmail author
  • Andreas Wilhelm
  • Erhan Oztop
  • Jan Peters


Humans manage to adapt learned movements very quickly to new situations by generalizing learned behaviors from similar situations. In contrast, robots currently often need to re-learn the complete movement. In this paper, we propose a method that learns to generalize parametrized motor plans by adapting a small set of global parameters, called meta-parameters. We employ reinforcement learning to learn the required meta-parameters to deal with the current situation, described by states. We introduce an appropriate reinforcement learning algorithm based on a kernelized version of the reward-weighted regression. To show its feasibility, we evaluate this algorithm on a toy example and compare it to several previous approaches. Subsequently, we apply the approach to three robot tasks, i.e., the generalization of throwing movements in darts, of hitting movements in table tennis, and of throwing balls where the tasks are learned on several different real physical robots, i.e., a Barrett WAM, a BioRob, the JST-ICORP/SARCOS CBi and a Kuka KR 6.


Skill learning Motor primitives Reinforcement learning Meta-parameters Policy learning 



The project receives funding from the European Community’s Seventh Framework Programme under grant agreement no. ICT-248273 GeRT. The project receives funding from the European Community’s Seventh Framework Programme under grant agreement no. ICT-270327 CompLACS. The authors thank Prof. K. Wöllhaf from the University of Applied Sciences Ravensburg-Weingarten for supporting the Kuka KR 6 experiment.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Jens Kober
    • 1
    • 2
    Email author
  • Andreas Wilhelm
    • 3
  • Erhan Oztop
    • 4
    • 5
    • 6
  • Jan Peters
    • 1
    • 2
  1. 1.MPI for Intelligent SystemsTübingenGermany
  2. 2.TU DarmstadtDarmstadtGermany
  3. 3.University of Applied Sciences Ravensburg-WeingartenWeingartenGermany
  4. 4.NICTKyotoJapan
  5. 5.ATRKyotoJapan
  6. 6.Özyeğin UniversityIstanbulTurkey

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