Rule-Based Cooperative Lane Change Control to Avoid a Sudden Obstacle in a Multi-Lane Road

When an unexpected obstacle occupies some of the lanes on a multi-lane highway, connected vehicles (CVs) have an advantage in avoiding this obstacle cooperatively. For example, a CV that detects the obstacle first can notify the following vehicles of the obstacle using vehicle-to-vehicle (V2V) communication. In turn, the following vehicles can take action to avoid the obstacle smoothly. Ishihara et al. proposed a strategy in which vehicles that receive a message notifying them of an obstacle gradually adjust their time headway to double it if they are approaching the obstacle. Thus, vehicles in the closed lane can change lanes smoothly and safely. The usefulness of this strategy was confirmed in a simulation of a two-lane road using the traffic flow simulator SUMO. In this paper, we extend this strategy to adapt three or more lanes. In the extended scheme, each vehicle approaching the obstacle selects a lane to which it changes according to the location of the obstacle and the vehicle density in each lane obtained through V2V communication, thereby improving traffic fairness among all lanes without deteriorating ride comfort. We conducted simulations with three-lane road scenarios. The simulation results show that the proposed scheme can achieve sufficiently high traffic throughput without degrading the comfort/safety and the fairness among lanes. Videos of the simulation results are available at: https://www.youtube.com/watch?v=0sDAJOZF38I.