Patent ID: 8103448
Filing Date: 2012-01-24
Classification: G01C

Abstract:
1. A new road information storage apparatus for use in a vehicle comprising: a road map data retrieval unit that retrieves a first set of road map data; a current position detector that detects a current position of the vehicle; a current position determiner that determines that the current position of the vehicle belongs to none of plural roads in the first set of road map data based on positional information of the plural roads; a data size estimator that estimates an incremental data size of a second set of road map data based on structure information of a new road when the new road that is defined as a set of vehicle positions that are determined not to be belonging to any of the plural roads in the first set of the road map data by the current position determiner is added to the second set of road map data; and a storage unit that stores positional information of the new road together with the incremental data size regarding the new road estimated by the data size estimator, wherein the data size estimator estimates the incremental data size in proportion to a length of the new road, a content of the first set of road map data is identical to a content of the second set of road map data, the data size estimator determines a relationship between a length of a specific road in the first set of road map data and a data size of the specific road in the first set of road map data, and a data size estimator that estimates an incremental data size of a second set of road map data based on structure information of a new road when the new road that is defined as a set of vehicle positions that are determined not to be belonging to any of the plural roads in the first set of the road map data by the current position determiner is added to the second set of road map data; and a storage unit that stores positional information of the new road together with the incremental data size regarding the new road estimated by the data size estimator, wherein the data size estimator estimates the incremental data size regarding the new road in proportion to a number of intersections included in the new road, a content of the first set of road map data is identical to a content of the second set of road map data, the data size estimator determines a relationship between the number of intersections in the first set of road map data and a data size of the intersections in the first set of road map data, and the data size estimator estimates the incremental data size based on the determined relationship and the number of intersections in the new road.