Method for testing the functionality of a rotation rate sensor

• US 9,927,240 B2
• Filed: 11/24/2015
• Issued: 03/27/2018
• Est. Priority Date: 12/15/2014
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Ohms, Torsten
• Primary Examiner(s): Gray, Francis
• Application Number:
  US14/950,937
• Publication Number:
  US 20160169933A1
• Time in Patent Office: 854 Days
• CPC Class Codes: G01C 19/5705 using masses driven in reciprocating rotary motion about an axis
• CPC Class Codes: G01C 19/5726 Signal processing

Abstract

A method for testing the functionality of a rotation rate sensor, the rotation rate sensor including a substrate and a micromechanical structure oscillatory with respect to the substrate having a first drive element, a second drive element and at least one Coriolis element, the Coriolis element being excitable to at least one oscillation mode by the first drive element and/or by the second drive element, a detection signal being detected as a function of a force action to be detected on the Coriolis element, the rotation rate sensor being operable optionally in a normal mode or in a self-test mode, the first drive element and the second drive element being driven in the normal mode, characterized in that in the self-test mode, the first drive element or the second drive element is driven optionally exclusively.

Claims

1. A method for testing a functionality of a rotation rate sensor, the method comprising:

exciting at least one Coriolis element of the rotation rate sensor to at least one oscillation mode by a first drive element and/or by a second drive element, wherein the rotation rate sensor includes a substrate and a micromechanical structure oscillatory with respect to the substrate having the first drive element, the second drive element and the at least one Coriolis element; and

detecting a detection signal as a function of a force action to be detected on the Coriolis element, the rotation rate sensor being operable optionally in a normal mode or in a self-test mode, the first drive element and the second drive element being driven in the normal mode;

wherein in the self-test mode, the first drive element or the second drive element is driven optionally exclusively.

2. The method of claim 1, wherein, during an initial calibration task in the self-test mode, a detection signal is stored in a memory unit as a detection signal to be expected.

3. The method of claim 1, wherein, during a self-test task, the detection signal in the self-test mode is compared with the expected detection signal.

4. The method of claim 1, wherein a piece of error information is generated if the difference of the detection signal in the self-test mode and of the expected detection signal exceeds a predefined value.

5. A rotation rate sensor, comprising:

a substrate;

a micromechanical structure oscillatory with respect to the substrate having a first drive element, a second drive element and at least one Coriolis element, the substrate having a main plane of extension, the rotation rate sensor being configured so that the Coriolis element is excitable to at least one oscillation mode by the first drive element and/or by the second drive element;

a detection arrangement to detect a force action to be detected on the Coriolis element, the rotation rate sensor being configured so that the rotation rate sensor is operable optionally in a normal mode or in a self-test mode, the rotation rate sensor being configured so that the first drive element and the second drive element are driven in the normal mode, wherein the rotation rate sensor is configured so that in the self-test mode, the first drive element or the second drive element is driven optionally exclusively.

6. The rotation rate sensor of claim 5, wherein the at least one Coriolis element includes a first Coriolis element and a second Coriolis element, and wherein the Coriolis element carries out a drive movement essentially in parallel to the main plane of extension of the rotation rate sensor and, in the case of a rotation rate to be detected, it experiences a force action along a detection direction, the detection direction extending perpendicularly to the main plane of extension.

7. A method for testing a functionality of a rotation rate sensor, the method comprising:

exciting at least one Coriolis element of the rotation rate sensor to at least one oscillation mode by a first drive element and/or by a second drive element, wherein the rotation rate sensor includes a substrate and a micromechanical structure oscillatory with respect to the substrate having the first drive element, the second drive element and the at least one Coriolis element; and

detecting a detection signal as a function of a force action to be detected on the Coriolis element, the rotation rate sensor being operable optionally in a normal mode or in a self-test mode, the first drive element and the second drive element being driven in the normal mode;

wherein in the self-test mode, the first drive element or the second drive element is driven optionally exclusively,

wherein, during a self-test task, the detection signal in the self-test mode is compared with the expected detection signal.

8. A method for testing a functionality of a rotation rate sensor, the method comprising:

exciting at least one Coriolis element of the rotation rate sensor to at least one oscillation mode by a first drive element and/or by a second drive element, wherein the rotation rate sensor includes a substrate and a micromechanical structure oscillatory with respect to the substrate having the first drive element, the second drive element and the at least one Coriolis element; and

detecting a detection signal as a function of a force action to be detected on the Coriolis element, the rotation rate sensor being operable optionally in a normal mode or in a self-test mode, the first drive element and the second drive element being driven in the normal mode;

wherein in the self-test mode, the first drive element or the second drive element is driven optionally exclusively,

wherein a piece of error information is generated if the difference of the detection signal in the self-test mode and of the expected detection signal exceeds a predefined value.

9. A rotation rate sensor, comprising:

a substrate;

a micromechanical structure oscillatory with respect to the substrate having a first drive element, a second drive element and at least one Coriolis element, the substrate having a main plane of extension, the rotation rate sensor being configured so that the Coriolis element is excitable to at least one oscillation mode by the first drive element and/or by the second drive element;

a detection arrangement to detect a force action to be detected on the Coriolis element, the rotation rate sensor being configured so that the rotation rate sensor is operable optionally in a normal mode or in a self-test mode, the rotation rate sensor being configured so that the first drive element and the second drive element are driven in the normal mode,

wherein the rotation rate sensor is configured so that in the self-test mode, the first drive element or the second drive element is driven optionally exclusively, wherein the at least one Coriolis element includes a first Coriolis element and a second Coriolis element, and wherein the Coriolis element carries out a drive movement essentially in parallel to the main plane of extension of the rotation rate sensor and, in the case of a rotation rate to be detected, it experiences a force action along a detection direction, the detection direction extending perpendicularly to the main plane of extension.