Urban Traffic Light Control via Active Multi-Agent Communication and Supply-Demand Modeling

Urban traffic light control is an important and challenging real-world problem. By regarding intersections as agents, most of the reinforcement learning-based methods generate agents' actions independently. They can cause action conflict and result in overflow or road resource waste in adjacent intersections. Recently, some collaborative methods have alleviated the above problems by extending the observable surroundings of agents, which can be considered inactive cross-agent communication methods. However, when agents act synchronously in these works, the perceived action value is biased, and the information exchanged is insufficient. In this work, we first propose a novel Multi-agent Communication and Action Rectification (MaCAR) framework. It enables active communication between agents by considering the impact of synchronous actions of agents. Another fundamental problem of traffic light control is the balance between traffic demand and road supply capacity. To fully describe the relation between traffic demand and road supply capacity (Supply-Demand modeling, SD), we further model and forecast the Supply-Demand relation to facilitating the effectiveness of the model's action. The experiments show that our model outperforms state-of-the-art methods on both synthetic and real-world datasets. Combining the SD with MaCAR, SD-MaCAR can further boost the traffic light control performance even in traffic accident scenarios.