The Impact of Urban Guide Signs on the Cost of Stochastic Equilibrium Networks Under Heterogeneous Traffic Flow

Urban guide signs provide drivers with essential information about roads, areas, key public facilities, and directions needed to reach their destinations. And analyzing the impact of guide signs at the network level and selecting reasonable placement schemes is necessary. With the advancement of IoT and autonomous driving technologies, Connected and Autonomous Vehicles (CAVs) are becoming increasingly prevalent in daily life. When analyzing the network-level impact of guide signs, it is crucial to account for the differences in route choice behavior between CAV and Human-Driven Vehicle (HDV) users due to their varying information acquisition capabilities and decision-making rationality, as well as the different impacts guide signs have on these two user groups. This study analyzes the role of urban guide signs and their impact mechanism on HDV users, proposing a diagonal matrix-based structural representation to describe the function of guide signs within the network. Numerical analysis shows that urban guide signs can influence the network costs between the signs and their guided destinations, aligning with the Bellman optimality principle observed in real-world routing processes. As the CAV penetration rate increases, the influence of guide signs on total network cost gradually diminishes. In a fully CAV-based network, guide signs have no effect on network equilibrium flow or network cost. The research findings provide a theoretical reference for the utility analysis of guide sign placement and the selection of signboard information.