Model-free Reinforcement Learning for Robust Locomotion using Demonstrations from Trajectory Optimization

Model-free Reinforcement Learning for Robust Locomotion using Demonstrations from Trajectory Optimization

M. Bogdanovic, M. Khadiv, L. Righetti

Frontiers in Robotics and AI, 2022.

[Full text]

We present a general, two-stage reinforcement learning approach to create robust policies that can be deployed on real robots without any additional training using a single demonstration generated by trajectory optimization. The demonstration is used in the first stage as a starting point to facilitate initial exploration. In the second stage, the relevant task reward is optimized directly and a policy robust to environment uncertainties is computed. We demonstrate and examine in detail the performance and robustness of our approach on highly dynamic hopping and bounding tasks on a quadruped robot.
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Hopping task

Variety of behavior from a single demonstration

Robustness to ground configurations not explicitly trained for

Robustness to external perturbations without explicit training for it

Bounding task

Variety of behavior from a single demonstration

Robustness to ground configurations not explicitly trained for

Robustness to external perturbations without explicit training for it