Semantic Tracklets: An Object-Centric Representation
for Visual Multi-Agent Reinforcement Learning

University of Illinois at Urbana-Champaign (UIUC)

International Conference on Intelligent Robots and Systems (IROS), 2021




Abstract

Solving complex real-world tasks, e.g., autonomous fleet control, often involves a coordinated team of multiple agents which learn strategies from visual inputs via reinforcement learning. Many existing multi-agent reinforcement learning (MARL) algorithms however don’t scale to environments where agents operate on visual inputs. To address this issue, algorithmically, recent works have focused on non-stationarity and exploration. In contrast, we study whether scalability can also be achieved via a disentangled representation. For this, we explicitly construct an object-centric intermediate representation to characterize the states of an environment, which we refer to as ‘semantic tracklets.’ We evaluate ‘semantic tracklets’ on the visual multi-agent particle environment (VMPE) and on the challenging visual multi-agent GFootball environment. ‘Semantic tracklets’ consistently outperform baselines on VMPE, and achieve a +2.4 higher score difference than baselines on GFootball. Notably, this method is the first to successfully learn a strategy for five players in the GFootball environment using only visual data.



Videos: Qualitative results for GFootball 11 vs. 11 (N=5)

Following the visualization scheme in the main paper, we highlight the ball in yellow. The videos are best viewed in full-screen mode.
We visualize the policy learned by our approach in the GFootball 11 vs. 11 game controlling five agents.

Videos: Qualitative results for GFootball 11 vs. 11 (N=3)

We visualize the policy learned by our approach in the GFootball 11 vs. 11 game controlling three agents.


Citation

@inproceedings{semtrack-2021,
  title = {Semantic Tracklets: An Object-Centric Representation for Visual Multi-Agent Reinforcement Learning},
  author = {Iou-Jen Liu$^\ast$ and Zhongzheng Ren$^\ast$ and Raymond A. Yeh$^\ast$ and Alexander G. Schwing},
  booktitle = {IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)},
  year = {2021},
  note = {$^\ast$ equal contribution},
}

Acknowledgement

This work is supported in part by NSF under Grant #1718221, 2008387, 2045586, and MRI #1725729, UIUC, Samsung, Amazon, 3M, and Cisco Systems Inc. RY is supported by a Google Fellowship.