Scene-Aware Explainable Multimodal Trajectory Prediction
Pei Liu, Haipeng Liu, Xingyu Liu, Yiqun Li, Junlan Chen, Yangfan He, Jun Ma
TL;DR
The paper addresses the need for joint reasoning across interacting agents and explainability in autonomous driving trajectory prediction. It introduces DMTP, a conditional diffusion‑based, multimodal framework with a Shapley‑value–based explainability module that provides global and scene‑level insights into feature importance. Through Waymo Open Motion Dataset experiments, DMTP achieves superior predictive accuracy while revealing interpretable input influences that align with human driving intuition. The work demonstrates both improved performance and practical interpretability, and makes the code openly available for reuse.
Abstract
Advancements in intelligent technologies have significantly improved navigation in complex traffic environments by enhancing environment perception and trajectory prediction for automated vehicles. However, current research often overlooks the joint reasoning of scenario agents and lacks explainability in trajectory prediction models, limiting their practical use in real-world situations. To address this, we introduce the Explainable Conditional Diffusion-based Multimodal Trajectory Prediction (DMTP) model, which is designed to elucidate the environmental factors influencing predictions and reveal the underlying mechanisms. Our model integrates a modified conditional diffusion approach to capture multimodal trajectory patterns and employs a revised Shapley Value model to assess the significance of global and scenario-specific features. Experiments using the Waymo Open Motion Dataset demonstrate that our explainable model excels in identifying critical inputs and significantly outperforms baseline models in accuracy. Moreover, the factors identified align with the human driving experience, underscoring the model's effectiveness in learning accurate predictions. Code is available in our open-source repository: https://github.com/ocean-luna/Explainable-Prediction.
