| 摘要 |
PROBLEM TO BE SOLVED: To provide a present position calculation device capable of calculating a correct present position. SOLUTION: Concerning a road wherein each road after being branched is extended approximately in parallel mutually, a branch link corresponding to a branched part is constituted so that a coefficientαvalue is reduced as much as a prescribed ratio when calculating an error cost value ec of a display candidate point belonging to the branch link. Consequently, since the value of a term of an azimuth differenceΔθof the error cost value ec is reduced, an influence exerted from the azimuth differenceΔθon the error cost value ec and an accumulated error cost es can be reduced. Hereby, since a value of reliability trst can be prevented from being reduced unfairly even when an extension azimuth of a lane on a branched/joined part is different greatly from a link azimuth of the branched link, the correct present position of a vehicle can be calculated by suppressing wrong determination of a wrong display candidate point as the present position of the vehicle. COPYRIGHT: (C)2008,JPO&INPIT |
