Method to determine the position and orientation of a mobile system, especially the line of sight in a helmet visor

Abstract

A method for determining a position and an orientation of a system that is mobile with respect to a transmitter of an electromagnetic field, the mobile system being placed in a carrier and being linked to a magnetic field sensor. The method including a first step of analytic modeling of the electromagnetic fields as a function of the coordinates of the sensor, a first field (B.sub.0) being created by the transmitter, a second field (B.sub.1) being created by the electrical currents induced in the carrier by the first field (B.sub.0), and a third field (B.sub.2) being created by the electrical currents induced in the mobile system by the first two fields (B.sub.0 +B.sub.1), the magnetic effect of each field (B.sub.0, B.sub.1, B.sub.2) being characterized independently of the effects of the other fields by the coefficients of a model thereof. The method further including a second step of real-time computation of the position and orientation of the sensor by using a current measurement of the electromagnetic field at the sensor and by using the models of the fields (B.sub.0, B.sub.1, B.sub.2) from the first step, the position and orientation of the sensor being defined from a measured field (B.sub.m) from which the third field (B.sub.2) is deduced. The method has applications in determining the position and orientation of the line of sight in a helmet visor.

Dependencies are inferred from the claim text.