Chaotic jam and phase transitions in heterogeneous lattice model integrating the delay characteristics difference with passing effect under autonomous and human-driven vehicles environment

Abstract

In heterogeneous traffic flow, the response delay of different types' vehicles varies. Accordingly, a heterogeneous lattice model is created for the mixed traffic flows including autonomous vehicles and human-driven vehicles accounting for the delay difference characteristics with the passing effect. The neutral stability condition is acquired from the linear stability analysis, which shows that the stability region of the system significantly decreases with the increase of the passing effect, the proportion of regular vehicles and the reaction time coefficient. The kink-antikink solution of the modified Korteweg-de Vries equation is inferred via nonlinear analysis. The jamming transitions occur between the kink jam and no jam regions with lower passing effect. When the passing effect increases to a critical value, a chaotic jam region appears between the kink jam and no jam regions. And the chaotic jam region further expands with higher passing effect. Moreover, simulation experiments indicate that traffic stability gets better with the delayed time falling down in heterogeneous traffic flow. Also, the impact factors of chaos phenomenon, including the passing effect, the delayed time and proportion of regular vehicles, are investigated in heterogeneous lattice model through Poincaré phase diagram and Lyapunov exponent.