MEMS – Magnetometer?
Hey, I don't quite understand how exactly this device works.
"The MEMS structures of the magnetometer include torsional structures, torsional beams, metal plates, a coil, and a glass substrate (Figure 1). The Lorentz force arises from the current in the coil and the external horizontal magnetic field and leads to differential displacements of the torsional structure, which can be detected with two sensor capacitors fabricated on the torsional structure. The torsion occurs along the y-axis. All directions of rotation comply with the right-hand rule."
How exactly are the cardinal directions recorded?
How exactly can one imagine the shift of the torsional structure.
Best regards
(No Ratings Yet)
Loading...
a) the magnetic field lines of the earth extend from (magnetic) pole to pole, that is quite exactly in the north-south direction – at least in our widths.
If 3 of these sensors are now arranged at a 90° angle to each other (=three axis magnetometer), the resultant can be calculated from the field strengths which the individual sensors supply and thus has the exact direction of the external magnetic field in relation to the 3-axis sensor.
b) the structure does not shift, but tries to rotate about the y-axis or to align it in the external magnetic field, similar to a compass needle. The two parts marked “torsional beam” along the y-axis represent the axis of rotation.