Abstract:

Focusing on the issue of mixed traffic flow composed of autonomous vehicular platoons and human-driven vehicles， and considering the inherent dynamics of vehicular platoon and the coupling with traffic flow， this work aims to investigate the property of mixed traffic flow when accounting for the actual dynamics of vehicular platoon. A model describing the relationship between the randomization probability of platoon and the variables dominating platoon dynamics including time headway and platoon size is proposed. Then a cellular automata （CA） mixed traffic flow model mixed with vehicular platoon and human-driven vehicles under open boundary condition is established. It is demonstrated from numerical simulations that the new model taking account the platoon inherent dynamics presented in this work， can reveal more particular phenomena of mixed traffic flow which cannot be reflected by the existing models. The characteristics of mixed traffic flow when considering the inherent dynamics of vehicular platoon is generally considerably affected by the typical features of platoon such as time headway， platoon size. Also， with the variations of vehicle density， more complex or even nonlinear relationship phenomenon has been observed. Generally， the effects of time headway and platoon size on mixed traffic flow are twofold， and increasing platoon penetration and platoon size can obviously improve the property of mixed traffic flow， and this advantage is more obvious in relatively high vehicle density scenarios to enhance the travelling capability.

Key words: transportation planning and management, intelligent transportation, vehicular platoon, cellular automata, mixed traffic flow