Magnetic azimuth sensor compensation apparatus for vehicle navigation system and method thereof
First Claim
1. A vehicle-mounted navigation apparatus comprising:
- a magnetic azimuth sensor for establishing first azimuth data by detecting magnetic field of the earth;
a distance sensor establishing distance data indicative of a moving distance of a vehicle;
means for calculating first position data indicative of a calculated present position of said vehicle by using said magnetic azimuth sensor and said distance sensor;
means for calculating biased center data of said magnetic azimuth sensor based on said first position data;
a global positioning system establishing second position data indicative of an actual present position of said vehicle;
means for calculating second azimuth data indicating an azimuth of said vehicle by using said biased center data and said second position data established by said global positioning system;
means for comparing said first position data and said second position data; and
means for establishing compensation data for compensating said biased center data based on said second azimuth data and said first position data to obtain new center data of said magnetic azimuth sensor when said first position data and said second position data are not substantially equal.
0 Assignments
0 Petitions
Accused Products
Abstract
A motor vehicle-mounted navigation apparatus comprising an input section adapted for inputting data based on GPS positioning, an azimuth sensor and distance sensor adapted for establishing independent navigation signal input sections for inputting data relating to a present position of motor vehicle and an azimuth thereof based on self-determining type navigation. The motor vehicle-mounted navigation apparatus further includes a control unit for determining the present position of the motor vehicle based on the obtained data through the input sections as described above, whereby error correction for the azimuth sensor is implemented by feeding back an output signal the control unit.
59 Citations
24 Claims
-
1. A vehicle-mounted navigation apparatus comprising:
-
a magnetic azimuth sensor for establishing first azimuth data by detecting magnetic field of the earth; a distance sensor establishing distance data indicative of a moving distance of a vehicle; means for calculating first position data indicative of a calculated present position of said vehicle by using said magnetic azimuth sensor and said distance sensor; means for calculating biased center data of said magnetic azimuth sensor based on said first position data; a global positioning system establishing second position data indicative of an actual present position of said vehicle; means for calculating second azimuth data indicating an azimuth of said vehicle by using said biased center data and said second position data established by said global positioning system; means for comparing said first position data and said second position data; and means for establishing compensation data for compensating said biased center data based on said second azimuth data and said first position data to obtain new center data of said magnetic azimuth sensor when said first position data and said second position data are not substantially equal. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of compensating a navigation system having a magnetic azimuth sensor for detecting magnetic field of the earth and a global positioning system, comprising the steps of:
-
(a) establishing first azimuth data by said magnetic azimuth sensor; (b) establishing distance data indicative of a moving distance of a vehicle; (c) calculating first position data indicative of a calculated present position of said vehicle by using said first azimuth data and said distance data; (d) calculating biased center data of said magnetic azimuth sensor based on said first position data; (e) establishing second position data indicative of an actual present position of said vehicle by said global positioning system; (f) calculating second azimuth data indicating an azimuth of said vehicle by using said biased center data and said second position data established by said step (e); (g) comparing said first position data and said second position data; and (h) establishing compensation data for compensating said biased center data based on said second azimuth data and said first position data to obtain new center data of said magnetic azimuth sensor when said first position data and said second position data are not substantially equal. - View Dependent Claims (8, 9, 10, 11)
-
-
12. A vehicle-mounted navigation apparatus comprising:
-
a magnetic azimuth sensor for establishing azimuth data by detecting earth'"'"'s magnetism; a distance sensor for establishing distance data indicative of a moving distance of a vehicle; means for calculating first position data indicative of a calculated present position of said vehicle by using said magnetic azimuth sensor and said distance sensor; means for calculating biased center data of said magnetic azimuth sensor based on said first position data; a global positioning system establishing second position data indicative of an actual present position of said vehicle; means for determining whether the second position data established by said global positioning system is within a predetermined range of said biased center data; means for calculating second azimuth data indicating an azimuth of the vehicle from said second position data and said biased center data when said first position data is within a predetermined range; means for comparing said second azimuth data with said first position data; means for outputting said first position data when said second position data and said first position data are substantially equal; correcting means for correcting a magnetization error introduced in said first position data caused in a magnetic environment by calculating new center data of said magnetic azimuth sensor from said first position data and said second azimuth data; and means for outputting said new center data of said magnetic azimuth sensor if the new center data is within a dynamic range of said magnetic azimuth sensor, and applying a correcting voltage to said new center data if the new center data is outside said dynamic range of said magnetic azimuth sensor so that the new center data is kept within said dynamic range. - View Dependent Claims (13, 14, 15, 16, 17)
-
-
18. A method of compensating a navigation system having a magnetic azimuth sensor for detecting magnetic field of the earth and a global position system, comprising the steps of:
-
(a) establishing magnetic azimuth data by said magnetic azimuth sensor; (b) establishing distance data indicative of a moving distance of a vehicle; (c) calculating first position data indicative of a calculated present position of said vehicle by using said magnetic azimuth data and said distance data; (d) calculating biased center data of said magnetic azimuth sensor based on said first position data; (e) establishing second position data indicative of an actual present position of said vehicle by said global positioning sensor; (f) determining whether the second position data established by said step (e) is within a predetermined range of said biased center data; (g) calculating said second azimuth data indicating an azimuth of the vehicle from said second position data and said biased center data when said first position data is within a predetermined range; (h) comparing said second azimuth data with said first position data; (i) outputting said first position data when said second position data and said first position data are substantially equal; (j) correcting a magnetization error introduced in said first position data caused in a magnetic environment by calculating new center data of said magnetic azimuth sensor from said first position data, and said second azimuth data; and (k) outputting said new center data of said magnetic azimuth sensor if the new center data is within a dynamic range of said magnetic azimuth sensor, and applying a correcting voltage to said new center data if the new center data is outside said dynamic range of said magnetic azimuth sensor so that the new center data is kept within said dynamic range. - View Dependent Claims (19, 20, 21, 22)
-
-
23. A vehicle-mounted navigation apparatus comprising:
-
a magnetic azimuth sensor for establishing first azimuth data by detecting magnetic field of the earth; distance sensor for establishing distance data indicative of a moving distance of a vehicle; means for calculating first position data indicative of a calculated present position of said vehicle by using said magnetic azimuth sensor and said distance sensor; means for calculating biased center data of said magnetic azimuth sensor based on said first position data; a global positioning system establishing second position data indicative of an actual present position of said vehicle; means for calculating second azimuth data indicating an azimuth of said vehicle by using said biased center data and said second position data established by said global positioning system; means for comparing said first position data and said second position data; means for establishing compensation data for compensation said biased center data based on said second azimuth data and said first position data when said first position data and said second position data are not substantially equal; and means for providing said compensation data to said magnetic azimuth sensor to compensate said first azimuth data of said magnetic azimuth sensor.
-
-
24. A method of compensating a navigation system having a magnetic azimuth sensor for detecting magnetic field of the earth and a global positioning system, comprising the steps of;
-
(a) establishing first azimuth data by said magnetic azimuth sensor; (b) establishing distance data indicative of a moving distance of a vehicle; (c) calculating first position data indicative of a calculated present position of said vehicle by using said first azimuth data and said distance data; (d) calculating biased center data of said magnetic azimuth sensor based on said first position data; (e) establishing second position data indicative of an actual present position of said vehicle by said global positioning system (f) calculating second azimuth data indicating an azimuth of said vehicle by using said biased center data and said second position data established by said step (c); (g) comparing said first position data and said second position data; (h) establishing compensation data for compensating said biased center data based on said second azimuth data and said first position data when said first position data and said second position data are not substantially equal; and (i) providing said compensation data to said magnetic azimuth sensor to compensate an output signal of said magnetic azimuth sensor.
-
Specification