🤖 AI Summary
Online signature verification typically relies on shallow temporal coordinate and pressure features, failing to capture the underlying biomechanical motion mechanisms of signers. To address this, we propose the first physics-consistent modeling framework grounded in Lagrangian mechanics, unifying 2D handwriting dynamics with 3D robotic arm kinematics to yield interpretable dynamic representations of signing behavior. We innovatively introduce the Lagrangian equation into biometric verification, designing both generative and discriminative temporal models under physical constraints, and integrating physics-guided neural embeddings with online time-series alignment. Evaluated on SigComp2024 and DeepSignDB benchmarks, our method achieves an 18.7% reduction in equal error rate (EER), significantly enhancing robustness against replay and imitation attacks. With inference latency under 35 ms, it satisfies real-time verification requirements.