Think Deep and Fast: Learning Neural Nonlinear Opinion Dynamics from Inverse Dynamic Games for Split-Second Interactions
Haimin Hu, Jaime Fernández Fisac, Naomi Ehrich Leonard, Deepak Gopinath, Jonathan DeCastro, Guy Rosman
TL;DR
The paper tackles the challenge of rapid, safe decision-making in non-cooperative multi-agent settings where deadlocks can occur. It introduces Neural Nonlinear Opinion Dynamics (Neural NOD) learned from inverse dynamic games, enabling online tuning of game costs via opinion-state dynamics. The approach combines a neural parameterization that maps states to time-varying cost weights with an offline training pipeline that differentiates through a forward game solver, plus analytical conditions for indecision-breaking through a pitchfork bifurcation. Empirical results in autonomous racing show Neural NOD outperforms state-of-the-art data-driven inverse game baselines on synthetic and human data, achieving safer and more decisive overtakes and demonstrating practical potential for fast, interpretable, and robust multi-agent planning.
Abstract
Non-cooperative interactions commonly occur in multi-agent scenarios such as car racing, where an ego vehicle can choose to overtake the rival, or stay behind it until a safe overtaking "corridor" opens. While an expert human can do well at making such time-sensitive decisions, autonomous agents are incapable of rapidly reasoning about complex, potentially conflicting options, leading to suboptimal behaviors such as deadlocks. Recently, the nonlinear opinion dynamics (NOD) model has proven to exhibit fast opinion formation and avoidance of decision deadlocks. However, NOD modeling parameters are oftentimes assumed fixed, limiting their applicability in complex and dynamic environments. It remains an open challenge to determine such parameters automatically and adaptively, accounting for the ever-changing environment. In this work, we propose for the first time a learning-based and game-theoretic approach to synthesize a Neural NOD model from expert demonstrations, given as a dataset containing (possibly incomplete) state and action trajectories of interacting agents. We demonstrate Neural NOD's ability to make fast and deadlock-free decisions in a simulated autonomous racing example. We find that Neural NOD consistently outperforms the state-of-the-art data-driven inverse game baseline in terms of safety and overtaking performance.
