Sensor control method

Patent metadata

Field	Value
Publication number	US-11834329-B2
Application number	US-202117301326-A
Country	US
Kind code	B2
Filing date	Mar 31, 2021
Priority date	Apr 3, 2020
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

The present description concerns a microelectromechanical sensor control method, including the steps of: exciting, with same first signal (FSL), a first resonant (206L) and at least one second resonant element (206R); and estimating a phase shift (Δφ) between the first signal and a second signal (FSR) which is an image of vibrations of the second resonant element.

First claim

What is claimed is:

1. Method of controlling a microelectromechanical sensor, comprising the steps of:
exciting, with a same first signal, a first resonant element and at least one second resonant element; and
estimating a phase shift between the first signal and a second signal which is an image of vibrations of the second resonant element, wherein said first and said at least one second resonant elements are located on either side of a seismic mass along an axis, the sensor being capable of detecting accelerations having a non-zero component when projected on said axis.

2. Method according to claim 1 , wherein, at equilibrium, the first and second resonant elements vibrate with a zero phase shift with respect to each other.

3. Method according to claim 1 , wherein the first signal is periodic and has a frequency substantially equal, preferably equal, to a resonance frequency of the first resonant element.

4. Method according to claim 3 , wherein the second resonant element has, when the sensor is in a position of equilibrium, a resonance frequency substantially equal, preferably equal, to the resonance frequency of the first resonant element.

5. Method according to claim 1 , wherein the first signal is imposed to the first resonant element by a feedback loop.

6. Method according to claim 1 , wherein the phase shift is estimated by a phase detector specific to each second resonant element.

7. Method according to claim 1 , wherein the sensor comprises one or a plurality of seismic masses, each second resonant element being coupled to said or to one of said seismic masses.

8. Method according to claim 7 , further comprising a step comprising exerting a feedback force on each seismic mass.

9. Method according to claim 8 , wherein the feedback force is generated by a feedback loop comprising a regulator, preferably a proportional and/or integral and/or derivative regulator, more preferably a proportional integral derivative regulator.

10. Method according to claim 7 , wherein the first resonant element is mechanically uncoupled from said seismic mass(es).

11. Circuit adapted to implementing the method according to claim 1 .

12. Microelectromechanical sensor comprising at least one circuit according to claim 11 .

13. One-axis sensor according to claim 12 , comprising exactly one second resonant element and one phase detector.

14. Three-axis sensor according to claim 12 , comprising three second resonant elements and three phase detectors.

15. Accelerometer comprising at least one sensor according to claim 12 .

16. Gyrometer comprising at least one sensor according to claim 12 .

Assignees

• Commissariat A Ienergie Atomique Et Aux Energies Alternatives
• Commissariat Energie Atomique

Inventors

• Sansa Perna Marc
• Defoort Martial

Classifications

• B81B7/007 Primary

  Interconnections between the MEMS and external electrical signals · CPC title

• B81B7/02

  containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] (B81B7/04 takes precedence) · CPC title

• G02F1/0123

  Circuits for the control or stabilisation of the bias voltage, e.g. automatic bias control [ABC] feedback loops · CPC title

• B81B2201/0235

  Accelerometers · CPC title

• B81B2201/0242

  Gyroscopes · CPC title