Process for compensating the magnetic disturbances in the determination of a magnetic heading, and devices for carrying out this process
First Claim
1. A device for compensating the magnetic disturbances influencing the measurements of a device which determines a magnetic heading on board a land vehicle comprising a magnetometer for furnishing analog voltages proportional to the components of the disturbed magnetic field of the earth, along reference axes of the magnetometer, a memory of a computer module associated with the magnetometer for receiving so-called compensation coefficients, which make it possible to correct the information delivered by the magnetometer to obtain the real heading, wherein the device further comprises:
- means for identifying a closed plane geometrical figure described by an end of a first vector Hhp indicative of the disturbed magnetic field when the vehicle rotates on itself through 360°
on a horizontal plane;
means for transforming this closed geometrical figure into a circle of any radius centered on the origin of the reference axes of the magnetometer and representing the locus of an end of a second vector Hh representative of the non-disturbed magnetic field, andmeans for calculating the coefficients serving to define the correspondence between all the points of said closed geometrical figure and their homologues on said circle.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention relates to a process for compensating the magnetic disturbances influencing the measurements of a device for determining the magnetic heading, mounted on a land vehicle or aircraft, comprising a magnetometer furnishing analog voltages proportional to the components of the disturbed magnetic field of the earth along its reference axes. It is admitted that the locus of the end of the vector indicative of the field is an ellipse for a land vehicle and an ellipsoid for an aircraft, of which identification from the analog voltages and transformation into a circle or sphere centered at O, origin of the axes of the magnetometer, enable correction coefficients to be calculated which are introduced into the memory of a computer unit associated with the magnetometer in order to define at any instant a vector making with a reference axis of the magnetometer an angle corresponding to the real magnetic heading of the vehicle or of the aircraft.
-
Citations
15 Claims
-
1. A device for compensating the magnetic disturbances influencing the measurements of a device which determines a magnetic heading on board a land vehicle comprising a magnetometer for furnishing analog voltages proportional to the components of the disturbed magnetic field of the earth, along reference axes of the magnetometer, a memory of a computer module associated with the magnetometer for receiving so-called compensation coefficients, which make it possible to correct the information delivered by the magnetometer to obtain the real heading, wherein the device further comprises:
-
means for identifying a closed plane geometrical figure described by an end of a first vector Hhp indicative of the disturbed magnetic field when the vehicle rotates on itself through 360°
on a horizontal plane;means for transforming this closed geometrical figure into a circle of any radius centered on the origin of the reference axes of the magnetometer and representing the locus of an end of a second vector Hh representative of the non-disturbed magnetic field, and means for calculating the coefficients serving to define the correspondence between all the points of said closed geometrical figure and their homologues on said circle. - View Dependent Claims (2, 3, 4, 9, 10, 11, 12, 13, 14, 15)
-
-
5. A device for compensating the magnetic disturbances influencing the measurements of a device which determines a magnetic heading on board an aircraft comprising a magnetometer for furnishing analog voltages proportional to the components of the disturbed magnetic field of the earth along reference axes of the magnetometer, a memory of a computer module associated with the magnetometer for receiving so-called compensation coefficients which make it possible to correct the information delivered by the magnetometer to obtain the real heading, and further comprising:
-
means for examining the evolution of the module of the disturbed magnetic field of the earth in space, assuming that the module of the earth'"'"'s field is constant between two successive measurements, means for computing in iterative manner the compensation coefficients enabling the evolution of the module of the earth'"'"'s magnetic field to be returned from an ellipsoid to a theoretical sphere centered on the axes of the magnetometer, in order to define the correspondence between the disturbed measurements and the real measurements. - View Dependent Claims (6, 7, 8)
-
Specification