T2SG: Traffic Topology Scene Graph for Topology Reasoning in Autonomous Driving

TL;DR

This paper introduces T2SG, a novel scene graph for traffic topology in autonomous driving, generated by TopoFormer, which improves scene understanding and reasoning accuracy in traffic environments.

Contribution

The paper proposes a new Traffic Topology Scene Graph and a one-stage TopoFormer model with innovative layers for better traffic scene representation.

Findings

Outperforms existing methods on T2SG generation

Achieves 46.3 OLS on OpenLane-V2 benchmark

Enhances traffic topology reasoning in downstream tasks

Abstract

Understanding the traffic scenes and then generating high-definition (HD) maps present significant challenges in autonomous driving. In this paper, we defined a novel Traffic Topology Scene Graph, a unified scene graph explicitly modeling the lane, controlled and guided by different road signals (e.g., right turn), and topology relationships among them, which is always ignored by previous high-definition (HD) mapping methods. For the generation of T2SG, we propose TopoFormer, a novel one-stage Topology Scene Graph TransFormer with two newly designed layers. Specifically, TopoFormer incorporates a Lane Aggregation Layer (LAL) that leverages the geometric distance among the centerline of lanes to guide the aggregation of global information. Furthermore, we proposed a Counterfactual Intervention Layer (CIL) to model the reasonable road structure ( e.g., intersection, straight) among lanes under counterfactual intervention. Then the generated T2SG can provide a more accurate and explainable description of the topological structure in traffic scenes. Experimental results demonstrate that TopoFormer outperforms existing methods on the T2SG generation task, and the generated T2SG significantly enhances traffic topology reasoning in downstream tasks, achieving a state-of-the-art performance of 46.3 OLS on the OpenLane-V2 benchmark. We will release our source code and model.