Proposed Asymmetric Microscopic Traffic Flow Theory

The paper presents a  microscopic asymmetric traffic flow theory based on detailed analysis of individual vehicle trajectories from the Next-Generation Simulation (NGSIM) database.  The findings clearly show the asymmetry in vehicle’s acceleration and deceleration and define five traffic phases: free flow, acceleration, deceleration, coasting, and stationary. The proposed theory provides detailed description and mechanism of phase transitions. Extensions of the basic theory address common driver behavioral characteristics such as maneuvering error and anticipation. The application of the proposed theory provides reasonable and intuitive explanations verified with experimental data on common traffic phenomena that cannot to date satisfactorily addressed by existing macroscopic or microscopic theories. These phenomena include traffic hysteresis, capacity drop, stability, relaxation after lane change, and stop-and-go traffic.