Patent ID: 8355864
Filing Date: 2013-01-15
Classification: G01C,G06F

Abstract:
1. A map matching system, comprising: a road network storing unit for storing data expressing a road network by a position of a node as a crossing and by an arc which is a road with a crossing as a start point and an end point; a road grid dividing unit for deriving a grid obtained by the division of a region where a road network exists in a latitude direction and a longitude direction by equal spaces and correlating the grid and an arc crossing the grid; a grid road combining unit for assigning a common arc ID to a plurality of grids which are adjacent to each other and whose sets of arcs correlated are coincident and assigning an arc ID to a grid whose set of arcs correlated is different from a set of arcs of any of adjacent grids and storing information indicative of a relationship among a range of a grid derived by said road grid dividing unit, a grid ID and an arc passing the grid to a storage device; an event collecting unit for receiving event data indicative of a position and a state of a vehicle; an event grid matching unit for specifying a grid ID of a grid to which a generation position included in event data received by said event collecting unit belongs to generate information with the grid ID and the event data correlated with reference to the information stored in said storage device; an event data selecting unit for selecting, on a basis of a grid ID correlated with event data by said event grid matching unit, when the number of pieces of event data correlated is larger than a threshold value, as many pieces of event data as the threshold value and when the number of pieces of event data correlated is not more than the threshold value, selecting all the event data correlated; an event road matching unit for specifying, on a basis of each event data selected by said event data selecting unit, an arc closest to a generation position of the event data from among arcs correlated with a grid ID corresponding to the event data; and an event road storing unit for storing information indicative of a correspondence relationship between an arc specified by said event road matching unit and event data.