A geocast solution to support CACC merging


Wouter Klein Wolterink


19 March 2010






In Cooperative Adaptive Cruise Control (CACC) the longitudinal speed of a vehicle is automatically controlled based on ad hoc communication with other vehicles. The expected main results of CACC are improved safety due to enhancement of the drivers reaction, and an overall traffic efficiency gain: CACC can anticipate better than the human driver to traffic disturbances, allowing vehicles to drive closer together. CACC vehicles must be explicitly told to make room for each other when this is necessary, for instance in a situation where a vehicle will want to merge on the highway. I will present a first approach to the design of a communication protocol needed in such a situation. The main challenge tackled here is how to reach only those vehicles that are responsible for creating a gap for a merging vehicle. A generic approach for defining the responsible vehicles is also presented.