End-to-end Reinforcement Learning for Torque Based Variable Height Hopping

Raghav Soni 1 Daniel Harnack 2 Hannah Isermann 2 Sotaro Fushimi 3 Shivesh Kumar 2 Frank Kirchner 2 4

Department of Electronics Engineering 1 German Research Center for Artificial Intelligence 2 Department of Mechanical and Systems Engineering 3 University of Bremen 4

Abstract

Legged locomotion is arguably the most suited and versatile mode to deal with natural or unstructured terrains. Intensive research into dynamic walking and running con- trollers has recently yielded great advances, both in the optimal control and reinforcement learning (RL) literature. Hopping is a challenging dynamic task involving a flight phase and has the potential to increase the traversability of legged robots. Model based control for hopping typically relies on accurate detection of different jump phases, such as lift-off or touch down, and using different controllers for each phase. In this paper, we present a end-to-end RL based torque controller that learns to implicitly detect the relevant jump phases, removing the need to provide manual heuristics for state detection. We also extend a method for simulation to reality transfer of the learned controller to contact rich dynamic tasks, resulting in successful deployment on the robot after training without parameter tuning.

Citation

@misc{Soni2023,
  author = {Soni, Raghav and Harnack, Daniel and Isermann, Hannah and Fushimi, Sotaro and Kumar, Shivesh and Kirchner, Frank},
  year = {2023},
  month = {10},
  pages = {},
  title = {End-to-end Reinforcement Learning for Torque Based Variable Height Hopping},
  doi = {}
}