US Patent 8219298 Lane change assist system

A lane change assist system is comprised of a host vehicle state detecting device that detects a host vehicle traveling condition, a surrounding vehicle detecting device that detects other vehicle located around the host vehicle, a lane detecting device that detects a lane around the host vehicle, and a processing unit. The processing unit is arranged to set a target lane, to determine a period of a lane change assist, to set a predicted period for an evaluation of a lane change to the target lane based on a prediction, to obtain an appropriate speed range during the predicted period for each gap, and to select a target vehicle speed from the appropriate speed range.