Sensor with a vibrating member in a cavity with integrated anomaly detection

摘要

The invention relates to vibrating micro-systems, and notably but not exclusively to pressure, acceleration, or angular speed micro-sensors with a resonator in an evacuated cavity.;The resonator (10) with a vibrating element is placed in an oscillating circuit controlled by a closed-loop control, the oscillating circuit supplying an oscillating signal y(t) at a resonance frequency Fp representing the measurement of a physical quantity. The resonance frequency is calculated by counting pulses over a time window. The sensor furthermore comprises means for calculating a continuity parameter Pc representing the variations in the result of the calculation of the resonance frequency over the course of the successive time windows, and means for comparing the parameter Pc with a threshold in order to deduce from this information on the degradation of the precision of the sensor.

主权项

1. A resonator measurement sensor, comprising
a resonator with a vibrating element placed in an oscillating circuit controlled by a closed-loop control, the oscillating circuit supplying an oscillating signal y(t) at a resonance frequency Fp representing the measurement of a physical quantity, and a processing circuit for calculating this resonance frequency, the processing circuit comprising means for conditioning the oscillating signal so as to produce a square-wave signal at the resonance frequency Fp, means for periodically producing a counting time window, at least one counter incremented by the square-wave signal at the resonance frequency during the counting time window, and means for calculating the resonance frequency from the content of the counter, the sensor being characterized in that it furthermore comprises means for calculating a continuity parameter Pc representing the variations in the result of the calculation of the resonance frequency over the course of successive time windows, and means for comparing the parameter Pc with a threshold in order to deduce from this information on the degradation in the precision of the sensor.