Cross-domain Imitation from Observations

    •  Raychaudhuri, D.S., van Baar, J., Paul, S., Roy-Chowdhury, A.K., "Cross-domain Imitation from Observations", International Conference on Machine Learning (ICML), June 2021.
      BibTeX TR2021-074 PDF
      • @inproceedings{Raychaudhuri2021jun,
      • author = {Raychaudhuri, Dripta S. and van Baar, Jeroen and Paul, Sujoy and Roy-Chowdhury, Amit K.},
      • title = {Cross-domain Imitation from Observations},
      • booktitle = {International Conference on Machine Learning (ICML)},
      • year = 2021,
      • month = jun,
      • url = {}
      • }
  • Research Areas:

    Artificial Intelligence, Machine Learning


Imitation learning seeks to circumvent the difficulty in designing proper reward functions for training agents by utilizing expert behavior. With environments modeled as Markov Decision Processes (MDP), most of the existing imitation algorithms are contingent on the availability of expert demonstrations in the same MDP as the one in which a new imitation policy is to be learned. In this paper, we study how to imitate tasks when discrepancies exist between the expert and agent MDP. These discrepancies across domains could include differing dynamics, viewpoint, or morphology; we present a novel framework to learn correspondences across such domains. Importantly, in contrast to prior works, we use unpaired and unaligned trajectories containing only states in the expert domain, to learn this correspondence. We utilize a cycle-consistency constraint on both the state space and a domain agnostic latent space to accomplish this. In addition, we enforce consistency on the temporal position of states via a normalized position estimator function, to align the trajectories across the two domains. Once this correspondence is found, we can directly transfer the demonstrations on one domain to the other and use it for imitation. Experiments across a wide variety of challenging domains demonstrate the efficacy of our approach.