Patent ID: 8653813

Claim:
An apparatus comprising a magnetic field vector sensor, said magnetic field vector sensor comprising a fixed substrate extending essentially parallel to a substrate plane, a mobile support, said mobile support being mobile relative to said fixed substrate and rotatable about at least a vertical rotation axis perpendicular to said substrate plane, a magnetic field source for generating a magnetic field having a magnetic moment in a direction that is not perpendicular to said substrate plane, said magnetic field source being fixed to said mobile support with no degree-of-freedom so as to exert a mechanical torque on said mobile support about said vertical rotation axis when a magnetic field to be measured is present, said magnetic field to be measured being non-collinear with said magnetic moment, at least one transducer adapted to convert said mechanical torque exerted on said mobile support about said vertical rotation axis into a signal representative of an amplitude of a component of said magnetic field to be measured along a measurement axis contained in said substrate plane, wherein said magnetic field source comprises a magnetostrictive permanent magnet for generating said magnetic field having said magnetic moment, said magnetic moment having a direction that varies as a function of mechanical stress exerted on said magnetostrictive permanent magnet, and wherein said magnetic field vector sensor further comprises a controllable device adapted to reversibly modify said direction of said magnetic moment of said magnetic field generated by said magnetic field source, said controllable device comprising a stress generator adapted to vary said mechanical stress exerted on said magnetostrictive permanent magnet to vary said direction of said magnetic moment thereof.