US 12,235,125 B2
Map data and map data generation method
Michiharu Yamamoto, Tokai (JP); and Hitoshi Aoyama, Tokai (JP)
Assigned to AICHI STEEL CORPORATION, Tokai (JP)
Appl. No. 17/778,020
Filed by Aichi Steel Corporation, Tokai (JP)
PCT Filed Nov. 20, 2020, PCT No. PCT/JP2020/043478
§ 371(c)(1), (2) Date May 19, 2022,
PCT Pub. No. WO2021/100866, PCT Pub. Date May 27, 2021.
Claims priority of application No. 2019-211865 (JP), filed on Nov. 22, 2019.
Prior Publication US 2022/0412769 A1, Dec. 29, 2022
Int. Cl. G01C 21/00 (2006.01); B60W 60/00 (2020.01); G08G 1/042 (2006.01)
CPC G01C 21/3815 (2020.08) [B60W 60/001 (2020.02); G01C 21/3841 (2020.08); G01C 21/3878 (2020.08); G08G 1/042 (2013.01); B60W 2556/40 (2020.02)] 20 Claims
OG exemplary drawing
 
1. A map data generation method of generating map data to be used by a vehicle which can measure magnetism acting from a road surface of a traveling road to estimate an own vehicle position, the method comprising processes of:
providing a structure map M1 representing at least a road structure and a road-surface magnetic distribution M2 in a blank state in which magnetic data is not associated therewith, the structure map M1 and the road-surface magnetic distribution M2 being associated with each other via position data indicating absolute positions to make respective positions in the road-surface magnetic distribution M2 uniquely correspond to respective positions in the structure map M1, thereby forming a layer data structure in which the structure map M1 and the road-surface magnetic distribution M2 mutually face each other,
acquiring a position of a measuring vehicle which includes a magnetic sensor;
measuring magnetic data on the road surface with the magnetic sensor; and
associating the magnetic data measured with the magnetic sensor with a point on the road-surface magnetic distribution M2 corresponding to the position of the measuring vehicle in a sequential manner as the measuring vehicle travels on the road surface, to make the road-surface magnetic distribution M2 represent a distribution of the magnetic data in a two-dimensional area on the road surface.