Stability of Vehicular Admission Control Schemes in Urban Traffic Networks Under Modeling Uncertainty

Traffic congestion in urban transportation networks causes significant environmental and socioeconomic impacts. Vehicular admission control (VAC) mitigates congestion by regulating vehicle entry over space and time using information and communication technologies. Despite extensive development, the stability of VAC schemes under modeling uncertainty remains under-explored. This work investigates the stability properties of a class of decentralized VAC schemes under modelling uncertainty. We consider large-scale, heterogeneous urban traffic networks characterised by nonlinear dynamics and concave macroscopic fundamental diagrams with bounded uncertainty between flow, density, and speed. In this context, we examine a broad class of decentralized VAC dynamics, described by general nonlinear forms. Using passivity theory, we derive scalable, locally verifiable conditions on the design of VAC schemes, that enable stability guarantees in the presence of modelling uncertainty. Examples are presented to illustrate the applicability of the proposed design framework. Numerical simulations on 6 and 20-region systems validate the analytical results and confirm their practical relevance.