Title:
NAVIGATION APPARATUS
Document Type and Number:
Japanese Patent JPH01178812
Kind Code:
A
Abstract:
PURPOSE:To correct the position coordinates of a vehicle with high accuracy by dead reckoning, by calculating a correction coefficient on the basis of the difference between the absolute coordinates of the predetermined point in the vicinity of a beacon arranged point and the position coordinates calculated by dead reckoning. CONSTITUTION:When it is judged that position code data is received from a beacon 10, the absolute coordinates of a beacon arranged point are calculated on the basis of the position code data to be replaced with the position coordinates of a dead reckoning start point. Road shape data is read from a memory apparatus 46. The output of an earth magnetism sensor 42 is taken in by a control apparatus 38 to calculate the coordinates of the present position. When it is judged that a vehicle reaches a inspection point, the coordinates of the inspection point are compared with uncorrected position coordinates to calculate error quantity. A correction coefficient is calculated on the basis of said error quantity and the position coordinates are calculated using this new correction coefficient.
Inventors:
SHIMA SUMITAKA
Application Number:
JP225388A
Publication Date:
July 17, 1989
Filing Date:
January 08, 1988
Export Citation:
Assignee:
TOYOTA MOTOR CORP
International Classes:
G01C21/00; G01S1/68; (IPC1-7): G01C21/00; G01S1/68
Domestic Patent References:
| JPS61117413A | 1986-06-04 |
Attorney, Agent or Firm:
Atsushi Nakajima (1 person outside)
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