System for measuring a magnetic field comprising a three-axis sensor for measuring a magnetic field that is able to move together with a carrier that disrupts the measurements, and associated method

Patent metadata

Field	Value
Publication number	US-9459098-B2
Application number	US-99238509-A
Country	US
Kind code	B2
Filing date	May 14, 2009
Priority date	May 14, 2008
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

The magnetic field measurement system comprises a triaxial main sensor ( 1 ) for measuring magnetic field that can move jointly with a carrier element ( 2 ) capable of generating at least one additional magnetic field disturbing the measurements of said triaxial main sensor ( 1 ), said triaxial sensor ( 1 ) being adapted for providing orthonormal measurements for a reference magnetic field in the absence of magnetic disturbances due to said carrier element ( 2 ). The system comprises means of adjustment ( 5, 6, 7, 9, 4 a, 4 b ) of said triaxial main sensor ( 1 ) comprising a removable additional sensor for magnetic field measurement, that can move jointly with said carrier element ( 2 ), and disposed outside said carrier element ( 2 ) away from the additional magnetic field or fields.

First claim

What is claimed is:

1. A triaxial magnetic field measurement system comprising a triaxial main sensor for measuring a magnetic field that can move jointly with a carrier element capable of generating at least one additional magnetic field disturbing measurements of said triaxial main sensor, said triaxial main sensor being configured to provide orthonormal measurements for a reference magnetic field in the absence of magnetic disturbances due to said carrier element, characterized in that the triaxial magnetic field measurement system further comprises means of adjustment of said triaxial main sensor comprising means for determining the reference magnetic field, said means for determining the reference magnetic field comprising a predetermined magnetic field generator or a removable additional sensor for magnetic field measurements, that can move jointly with said carrier element, and that is disposed outside said carrier element away from the additional magnetic field or fields.

2. The system as claimed in claim 1 , wherein said means of adjustment of said triaxial main sensor comprises means for determining the additional magnetic field or fields generated by said carrier element on the basis of parameters comprising coefficients representative of a magnetic sensitivity of said carrier element, measurements performed by said triaxial main sensor, and temporal variations of said measurements.

3. The system as claimed in claim 2 , wherein said means for determining the additional magnetic field or fields generated by said carrier element is a processing device configured to implement the following system of equations:

{

B

real
x

=

B

measured
x

-

(

B

remanent
x

+

A
×

V
x

)

B

real
y

=

B

measured
y

-

(

B

remanent
y

+

A
×

V
y

)

B

real
z

=

B

measured
z

-

(

B

remanent
z

+

A
×

V
z

)

,

in which:
B real x , B real y , and B real z represent the respective components of a real magnetic field along the three axes of the triaxial main sensor;
B measured x , B measured y , and B measured z represent respective components of the magnetic field measured by the triaxial main sensor along its three axes;
B remanent x , B remanent y , and B remanent z represent respective components of a remanent magnetic field along the three axes of the triaxial main sensor;

A
=

[

B

measured
x

;

B

measured
y

;

B

measured
z

;

∂

B

measured

Assignees

• Grenet Pierre
• El-Marfouq Ismaïl
• Cattin Viviane
• Movea
• Commissariat Energie Atomique

Inventors

• Grenet Pierre
• El-Marfouq Ismaïl
• Cattin Viviane

Classifications

• G01C17/38 Primary

  Testing, calibrating, or compensating of compasses · CPC title

• G01R33/025

  Compensating stray fields {(G01R33/0017 takes precedence)} · CPC title

• G01R33/0206

  Three-component magnetometers · CPC title