刷新NAVSIM SOTA，复旦引望提出Masked Diffusion端到端自动驾驶新框架

Core Insights - The article discusses the transition in end-to-end autonomous driving from a "modular" approach to a "unified" paradigm with the rise of Vision-Language-Action (VLA) models, highlighting the limitations of existing autoregressive generation paradigms [2] - It introduces the WAM-Diff framework, which innovatively incorporates discrete masked diffusion models into VLA autonomous driving planning, addressing the challenges of single-direction temporal generation [2][6] Group 1: WAM-Diff Framework - WAM-Diff utilizes Hybrid Discrete Action Tokenization to convert continuous 2D trajectory coordinates into high-precision discrete tokens, achieving an error control within 0.005 [6] - The framework employs Masked Diffusion as its backbone, allowing for parallel prediction of all token positions, significantly enhancing inference efficiency and enabling global optimization [6] - WAM-Diff explores decoding strategies, revealing that the reverse-causal strategy outperforms others in closed-loop metrics, validating the "end-to-begin" planning logic [9][20] Group 2: Performance Metrics - In the authoritative NAVSIM benchmark, WAM-Diff achieved state-of-the-art (SOTA) scores of 91.0 PDMS in NAVSIM-v1 and 89.7 EPDMS in NAVSIM-v2, demonstrating its potential in complex autonomous driving scenarios [3][18] - The model surpassed competitors like DiffusionDrive and ReCogDrive, indicating its robustness in balancing safety and compliance in real-world driving conditions [18] Group 3: Technical Innovations - WAM-Diff integrates a Low-Rank Adaptation Mixture-of-Experts (LoRA-MoE) architecture, which includes 64 lightweight experts for dynamic routing and sparse activation, enhancing model capacity and adaptability [11] - The Group Sequence Policy Optimization (GSPO) algorithm is introduced to bridge the gap between open-loop training and closed-loop execution, optimizing trajectory sequences based on safety, compliance, and comfort metrics [14] Group 4: Conclusion - The emergence of WAM-Diff marks a significant step towards discrete, structured, and closed-loop autonomous driving planning, emphasizing the importance of both "how to generate" and "what to generate" in the VLA era [25]