Navigation system

• US 8,571,789 B2
• Filed: 03/18/2008
• Issued: 10/29/2013
• Est. Priority Date: 07/04/2007
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Monde, Yasuhiro, Hayami, Katsuro, Fujii, Masatoshi, Maeda, Atsushi
• Primary Examiner(s): To, Tuan C.
• Assistant Examiner(s): Mahne, Kevin P
• Application Number:
  US12/601,732
• Publication Number:
  US 20100185390A1
• Time in Patent Office: 2,051 Days
• Field of Search: None
• US Class Current: 701/409
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices
• CPC Class Codes: G09B 29/102 using electrical means

Abstract

A navigation system includes: an angular velocity sensor 1 for detecting a change in an advancement direction of a vehicle; a vehicle azimuth calculation unit 13 for calculating a vehicle azimuth on the basis of angular velocity sensor information obtained from the angular velocity sensor; an on-board camera 2 for shooting a periphery of the vehicle; an image recognition unit 19 for recognizing an image obtained from the on-board camera; and an offset voltage correction unit 21 for performing a drift correction on the angular velocity sensor in accordance with an angle error between the vehicle azimuth calculated by the vehicle azimuth calculation unit and a vehicle azimuth determined from a white line on a road recognized by the image recognition unit.

Claims

1. A navigation system comprising:

an angular velocity sensor for detecting a change in an advancement direction of a vehicle;

a vehicle azimuth calculation unit for calculating a vehicle azimuth on the basis of angular velocity sensor information obtained from said angular velocity sensor;

a global positioning system (GPS) receiver for detecting a current position of a vehicle using the GPS;

a vehicle speed sensor for detecting rotation of a vehicle wheel;

a distance measurement unit for measuring a traveled distance on the basis of vehicle speed pulse information obtained from said vehicle speed sensor;

a map information storage unit for storing map information;

a current position calculation unit for calculating a current position on the basis of GPS information obtained from said GPS receiver, vehicle azimuth information obtained from said vehicle azimuth calculation unit, and distance information obtained from said distance measurement unit, and determining a current position of a vehicle on a map by comparing said calculated current position with said map information read from said map information storage unit;

an on-board camera for shooting a periphery of said vehicle;

an image recognition unit for recognizing an image obtained from said on-board camera; and

a road deviation determination unit for determining whether or not said vehicle has deviated from a traveling road by detecting a change in the movement of traffic other than said vehicle on a periphery of said vehicle that is recognized by said image recognition unit,

wherein said current position calculation unit further corrects said determined current position of said vehicle on the basis of a specific object recognized by said image recognition unit, and

wherein said current position calculation unit further corrects said determined current position of said vehicle on the basis of said determination by said road deviation determination unit as to whether or not said vehicle has deviated from said traveling road.

2. The navigation system according to claim 1, wherein said change in the movement of said traffic other than said vehicle on said periphery of said vehicle that is detected by said road deviation determination unit indicates a longitudinal direction flow or a lateral direction flow of said traffic in an image pattern recognized by said image recognition unit.