Micromechanical rotation rate sensor having error suppression

• US 7,523,663 B2
• Filed: 12/22/2005
• Issued: 04/28/2009
• Est. Priority Date: 12/22/2004
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Veith, Michael, Bauer, Wolfram, Gomez, Udo-Martin, Kuhlmann, Buckhard, Classen, Johannes, Lang, Christoph, Willig, Rainer
• Primary Examiner(s): Williams; Hezron
• Assistant Examiner(s): SHABMAN, MARK A
• Application Number:
  US11/317,819
• Publication Number:
  US 20060191338A1
• Time in Patent Office: 1,223 Days
• Field of Search: 735/141.2, 735/142, 735/041.2
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5726 Signal processing
• CPC Class Codes: G01C 19/5755 the devices having a single sensing mass

Abstract

A micromechanical rotation rate sensor has a seismic mass and driving devices which cause a driving vibration of the seismic mass in a first direction x. The rotation rate sensor has measuring devices which measure a deflection of the seismic mass in a second direction y, and generate a deflection signal. The deflection includes a measurement deflection caused by a Coriolis force and an interference deflection, the interference deflection being phase-shifted with respect to the measurement deflection by 90°. Compensation devices are provided at the seismic mass to reduce the interference deflection. Regulation devices are provided, to which the deflection signal is supplied as an input variable, which demodulate an interference deflection signal from the deflection signal, and which generate a compensation signal from the interference deflection signal, which is supplied to the compensation devices.

Claims

1. A micromechanical rotation rate sensor, comprising:

a seismic mass;

at least one driving device adapted to effect a driving vibration of the seismic mass in a first direction;

at least one measurement device adapted to measure a deflection of the seismic mass in a second direction and to generate a deflection signal, the deflection including a measurement deflection caused by a Coriolis force and an interference deflection, the interference deflection phase-shifted with respect to the measurement deflection substantially by 90°

;

at least one compensation device adapted to decrease the interference deflection and which engages with the seismic mass; and

at least one regulation device, the deflection signal supplied to the regulation device as an input variable, the regulation device adapted to demodulate, using a periodic signal having a frequency equal to the driving vibration and a phase equal to that of the interference deflection, an interference deflection signal from the deflection signal and to generate a compensation signal from the interference deflection signal, the compensation signal being supplied to the compensation device.

2. The micromechanical rotation rate sensor according to claim 1, wherein the regulation device is adapted to regulate the interference deflection tending to zero.

3. The micromechanical rotation rate sensor according to claim 1, wherein the regulation device includes an integration element.

4. The micromechanical rotation rate sensor according to claim 1, further comprising a controller adapted to generate an additional compensation signal from an adjustment value.

5. The micromechanical rotation rate sensor according to claim 4, wherein the regulation device is adapted to set a capture range of a digital-to-analog converter unit of the regulation device as a function of the adjustment value.

12. The micromechanical rotation rate sensor according to claim 1, further comprising:

a controller to generate an additional compensation signal from an adjustment value;

wherein the regulation device regulates the interference deflection tending to zero, wherein the regulation device includes an integration element, and wherein the regulation device sets a capture range of a digital-to-analog converter unit of the regulation device as a function of the adjustment value.

6. A micromechanical rotation rate sensor, comprising:

a seismic mass;

driving means for effecting a driving vibration of the seismic mass in a first direction;

measuring means for measuring a deflection of the seismic mass in a second direction and for generating a deflection signal, the deflection including a measurement deflection caused by a Coriolis force and an interference deflection, the interference deflection phase-shifted with respect to the measurement deflection substantially by 90°

;

compensating means for decreasing the interference deflection and which engage engages with the seismic mass; and

regulating means, the deflection signal supplied to the regulating means as an input variable, the regulation means for demodulating, using a periodic signal having a frequency equal to the driving vibration and a phase equal to that of the interference deflection, an interference deflection signal from the deflection signal and for generating a compensation signal from the interference deflection signal, the compensation signal being supplied to the compensating means.

7. The micromechanical rotation rate sensor according to claim 6, wherein the regulation means regulates the interference deflection tending to zero.

8. The micromechanical rotation rate sensor according to claim 6, wherein the regulation means includes an integration element.

9. The micromechanical rotation rate sensor according to claim 6, further comprising:

a controller to generate an additional compensation signal from an adjustment value.

10. The micromechanical rotation rate sensor according to claim 9, wherein the regulation means sets a capture range of a digital-to-analog conversion unit of the regulation means as a function of the adjustment value.

11. The micromechanical rotation rate sensor according to claim 6, further comprising:

a controller to generate an additional compensation signal from an adjustment value;

wherein the regulation means regulates the interference deflection tending to zero, wherein the regulation means includes an integration element, and wherein the regulation means sets a capture range of a digital-to-analog converter unit of the regulation means as a function of the adjustment value.