Method for calibrating magnetometers of an object

Method for calibrating magnetometers of an object moving in an ambient magnetic field, the method comprising:

• (a) acquiring
• by the magnetometers, at least three measured components of the magnetic field around the magnetometers, and
• by inertial measurement means which are secured to the object, an angular velocity of the object;
• (c) determining, by data processing means, values of at least one calibration parameter of the magnetometers minimising an expression defined by estimated components of the magnetic field and at least one magnetic equation relating to the angular velocity of the object,
• the estimated components of the magnetic field being a function of the measured components of the magnetic field as well as of calibration parameters of the magnetometers, and
• the at least one magnetic equation assuming that the magnetic field is uniform and stationary around the magnetic measurement means;
• wherein the magnetic equation is of the form M+−ω×M, where M is the vector of the components of the magnetic field, and ω the angular velocity, said expression being a function of M(estimation)+ωgyro(estimation)×M(estimation).