Abstract
This paper presents experiments with a morphology-independent, life-long strategy for online learning of locomotion gaits. The experimental platform is a quadruped robot assembled from the LocoKit modular robotic construction kit. The learning strategy applies a stochastic optimization algorithm to optimize eight open parameters of a central pattern generator based gait implementation. We observe that the strategy converges in roughly ten minutes to gaits of similar or higher velocity than a manually designed gait and that the strategy readapts in the event of failed actuators. We also optimize offline the reachable space of a foot based on a reference design but finds that the reality gap hardens the successfully transference to the physical robot. To address this limitation, in future work we plan to study co-learning of morphological and control parameters directly on physical robots.








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Acknowledgments
This work was performed as part of the “Locomorph” project funded by the EU’s Seventh Framework Programme (Future Emerging Technologies, Embodied Intelligence) and as part of the “Assemble and Animate” project funded by the Danish Council for Independent Research.
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Christensen, D.J., Larsen, J.C. & Stoy, K. Fault-tolerant gait learning and morphology optimization of a polymorphic walking robot. Evolving Systems 5, 21–32 (2014). https://doi.org/10.1007/s12530-013-9088-3
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DOI: https://doi.org/10.1007/s12530-013-9088-3