Integrating virtual obstacle into variable speed limit control for highways in connected traffic environments

Abstract

Variable speed limits (VSL), as a global control mechanism, present challenges in accurately regulating traffic flow on highway local road segments. This paper incorporates a novel virtual obstacle (VO) control into VSL with time-varying control sections in a connected environment to balance global and local traffic management. VO control dynamically creates, adjusts, and removes virtual obstacles to form controllable artificial bottlenecks. A highway traffic flow network model is first developed based on a link queue model, considering the effects of VSL and VO. Variable link length describes the time-varying VSL control section and VO position. Then, a multi-objective function is introduced within the model predictive control framework. An improved genetic algorithm is employed to optimize speed limits and control sections of the VSL, as well as the position and width of the VO. Experimental results indicate that the proposed coordinated control method effectively alleviates congestion compared to the VSL control.