Autonomous control in a dense vehicle environment

Method for operating vehicle in autonomous / semi-autonomous mode, receives a first data set from a sensor (e.g. radar / lidar / image data) located on the vehicle, and a second data set from at least one sensor on at least one second vehicle (i.e. inter vehicle communication, V2V), and uses both data sets to identify a road feature (e.g. lanes of travel, road curvature / slope / condition, highway entrance ramp, obstacles, weather condition, a third vehicle). An autonomous vehicle action may also be determined (e.g. braking, acceleration, lane change, change in lead vehicle distance). A virtual map may be constructed of the surrounding environment, including the identified feature(s). Data may be sent as a dedicated short range communications (DSRC) message. A system having a processor and memory is also claimed.