Combined Rotation and Magnetic Field Sensor Based on Lissajous FM Technique

In this paper, a combined sensor to detect both magnetic field and rotation based on Lissajous- FM (LFM) technique is proposed. Two axes of a slightly mode-mismatched 2-DOF resonator are coupled both by Coriolis and Lorentz forces. When the sensing current is applied in proportion to the oscillation displacement, angular rate and magnetic field could be independently detected by sum and difference of the frequencies. Also, these changes are orthogonal each other, therefore, they could be further separated by the orthogonal synchronous demodulation. The principle was confirmed by the numerical simulation. The frequencies were linearly modulated by both magnetic field and angular rate.