Precise curvature estimation by cooperating with digital road map

This paper proposed a novel algorithm for road geometry estimation ahead of vehicle depending on present vehicle localization. In order to provide precise and robust on-coming road geometry estimation under different environmental conditions, we employ a new hybrid vehicle localization approach combining the commercial GPS and inertial sensors. In this work, road geometry (planar curvature) is initially estimated from the prevalent digital road map following the rules of road construction design and basic geometrical elements (straight line, clothoid curve and circle curve). Therefore, road trajectory between vehicle and road ahead could be calculated by flexible road model, relying on precise curvature which has been designed beforehand. In simulation test, road geometrical curve within camerapsilas view range is built by variance curvature in meters. Meanwhile, road tests show similarity between simulation results and real road scenes. This approach is also proved effectiveness and robustness under different kinds of environment conditions.