Electrostatic coupling suppression circuit for quartz tuning fork gyroscope

Abstract

The invention provides an electrostatic coupling suppression circuit for a quartz tuning fork gyroscope. The electrostatic coupling suppression circuit comprises a quartz tuning fork sensor, a driving and amplitude control circuit, a phase inverting circuit, a compensating circuit, an angular velocity detection circuit and a demodulation filter circuit, output signals of the quartz tuning fork sensor respectively refer to a driving and amplitude control circuit and an angular velocity detection circuit, the driving and amplitude control circuit generates a driving signal according to an input signal, and the driving signal is also respectively input to a phase inverting circuit and a demodulation filter circuit; the inverting circuit generates a driving inverting signal with the same frequency and the same phase as the driving signal according to the driving signal, the driving signal and the driving inverting signal generate an electrostatic coupling compensation signal after passing through the compensation circuit, and the electrostatic coupling compensation signal is input into the angular velocity detection circuit and counteracts an electrostatic coupling error in the detection circuit; the angular velocity detection circuit generates an angular velocity carrier signal and an angular velocity carrier inversion signal, and outputs an angular velocity signal after passing through the demodulation filter circuit. According to the invention, the electrostatic error is reduced, and the whole gyroscope performance is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of quartz tuning fork gyroscope measurement and control circuits, and relates to an electrostatic coupling suppression circuit for a quartz tuning fork gyroscope. Background Art

[0002] At present, the static errors in the output of quartz tuning fork gyroscopes mainly include in-phase error and quadrature error. Both errors are directly related to the static zero performance of quartz tuning fork gyroscopes. In-phase error is mainly caused by the electrostatic coupling between the internal drive signal and the detection path of the gyroscope. The error signal has the same frequency and phase as the carrier signal of the angular velocity, so it is called "in-phase error" or "electrostatic error"; the quadrature error is mainly caused by the mechanical coupling between the drive mode and the detection mode caused by the processing error during the processing of the quartz tuning fork and the characteristics of the material itself. The error signal has the same frequency as the carrier signal of the angular velocity, and the phase difference is 90°, so it is called "quadrature error" or "mechanical error".

[0003] In practical applications, the in-phase error is usually suppressed by electromagnetic shielding or shortening the coupling path in the product; the orthogonal error is usually mechanically adjusted during the production process to reduce the impact of normal errors on the output. In the commonly used quartz tuning fork gyroscope measurement and control circuit, due to the presence of coupling capacitors in the sensor and electromagnetic coupling paths in space, the output signal of the detection circuit contains electrostatic coupling errors, and this error, like the drive signal, usually changes significantly with changes in external temperature. This change causes excess errors in the demodulated angular velocity demodulation signal, and ultimately causes the electrostatic error term in the angular velocity signal to change with temperature. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] To this end, the present invention provides an electrostatic coupling suppression circuit for a quartz tuning fork gyroscope. The circuit can suppress the electrostatic coupling of a driving signal in a driving circuit to a detection circuit (i.e., it can suppress the interference of an electrostatic error signal generated by electrostatic coupling to an angular velocity signal), reduce electrostatic errors, and thus improve the overall performance of the gyroscope.

[0006] The technical solution of the present invention is as follows:

[0007] According to one aspect, there is provided an electrostatic coupling suppression circuit for a quartz tuning fork gyroscope, the circuit comprising: a quartz tuning fork sensor, a drive and amplitude control circuit, an inverting circuit, a compensation circuit, an angular velocity detection circuit and a demodulation filter circuit;

[0008] The output signal of the quartz tuning fork sensor refers to the driving and amplitude control circuit and the angular velocity detection circuit respectively. The driving and amplitude control circuit generates a driving signal according to the output signal of the quartz tuning fork sensor.

[0009] The driving signal is also input into an inverting circuit and a demodulation and filtering circuit respectively; the inverting circuit generates a driving inverted signal with the same frequency and inverted phase according to the driving signal; the driving signal and the driving inverted signal generate an electrostatic coupling compensation signal after passing through a compensation circuit, and the signal is input into an angular velocity detection circuit to offset the electrostatic coupling error in the detection circuit; the angular velocity detection circuit generates an angular velocity carrier signal and an angular velocity carrier inverted signal, and the angular velocity signal is output after passing through a demodulation and filtering circuit.

[0010] Furthermore, the driving and amplitude control circuit includes a driving detection circuit, a driving signal circuit and an amplitude control circuit. The driving detection circuit is used to convert the charge signal representing the displacement of the driving fork fingers generated by the piezoelectric effect of the quartz tuning fork sensor into a voltage signal, and output the driving detection signal to the amplitude control circuit and the driving signal circuit respectively; the driving signal circuit generates a driving signal with the same frequency as the driving detection signal according to the driving detection signal; and the amplitude control circuit generates an amplitude control signal for controlling the amplitude of the driving signal by comparing the amplitude of the driving detection signal with a reference value.

[0011] Furthermore, the drive detection circuit is implemented by a charge amplifier.

[0012] Furthermore, the driving signal circuit is implemented by a comparator.

[0013] Furthermore, the demodulation and filtering circuit includes a demodulator and a filtering circuit, wherein a driving signal is input to the demodulator, an angular velocity carrier signal and an angular velocity carrier inversion signal generated by an angular velocity detection circuit are both input to the demodulator, and the demodulator is used to generate an angular velocity demodulation signal, and the angular velocity demodulation signal is filtered by the filtering circuit and then output as an angular velocity signal.

[0014] According to another aspect, a quartz tuning fork gyroscope is provided, the gyroscope comprising the electrostatic coupling suppression circuit described above.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] In the quartz tuning fork gyro measurement and control circuit of the present invention, in order to suppress the additional error generated by the driving signal in the angular velocity signal through electrostatic coupling, the electrostatic error signal in the output signal of the detection path is suppressed by the anti-phase coupling method, wherein the present invention obtains a driving anti-phase signal that is anti-phase to the driving signal by inverting the driving signal, and generates an electrostatic coupling compensation signal after the driving signal or the driving anti-phase signal is selected according to the polarity of the electrostatic coupling signal in the angular velocity signal through the compensation circuit, and this signal is then input into the detection circuit, and the electrostatic coupling signal in the detection circuit cancels each other, thereby eliminating the interference of the electrostatic coupling signal on the angular velocity measurement signal. That is, the present invention adopts the anti-phase coupling method to suppress the electrostatic coupling signal by improving the circuit design, greatly weakens the interference of the electrostatic error signal on the angular velocity measurement signal, and improves the performance of the whole table. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a schematic diagram of an electrostatic coupling suppression circuit of an improved quartz tuning fork gyroscope according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0021] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0022] like Figure 1 As shown, in one embodiment of the present invention, an electrostatic coupling suppression circuit for a quartz tuning fork gyroscope is provided, the circuit comprising: a quartz tuning fork sensor 1, a driving and amplitude control circuit 4, an inverting circuit 8, a compensation circuit 9, an angular velocity detection circuit 5 and a demodulation filter circuit 7; the output signal of the quartz tuning fork sensor 1 refers to the driving and amplitude control circuit 4 and the angular velocity detection circuit 5 respectively, the driving and amplitude control circuit 4 generates a driving signal 12 according to the output signal of the quartz tuning fork sensor 1, and the driving signal 12 is also input to the inverting circuit 8 and the demodulation filter circuit 7 respectively; the inverting circuit 8 generates a driving inverted signal 18 with the same frequency and inverted phase with the driving signal 12 according to the driving signal 12, the driving signal 12 and the driving inverted signal 18 are generated by the compensation circuit 9 after passing through the electrostatic coupling compensation signal 19, and are input to the angular velocity detection circuit 5 to offset the electrostatic coupling error in the detection circuit, the angular velocity detection circuit 5 generates an angular velocity carrier signal 14 and an angular velocity carrier inverted signal 15, and outputs an angular velocity signal 17 after passing through the demodulation filter circuit 7.

[0023] It can be seen that in order to suppress the additional error generated by the driving signal in the angular velocity signal through electrostatic coupling, the electrostatic error signal in the output signal of the detection path is suppressed by the anti-phase coupling method. The specific embodiment of the present invention obtains a driving anti-phase signal that is anti-phase to the driving signal by inverting the driving signal, and selects the driving signal or the driving anti-phase signal according to the polarity of the electrostatic coupling signal in the angular velocity signal. After passing through the compensation circuit, the electrostatic coupling compensation signal is generated. This signal is then input into the detection circuit, and the electrostatic coupling signal in the detection circuit is offset to eliminate the interference of the electrostatic coupling signal on the angular velocity measurement signal. That is, the embodiment of the present invention adopts the anti-phase coupling method to suppress the electrostatic coupling signal by improving the circuit design, greatly reducing the interference of the electrostatic error signal on the angular velocity measurement signal, and improving the performance of the whole meter.

[0024] According to one embodiment of the present invention, the driving and amplitude control circuit 4 includes a driving detection circuit 2, a driving signal 12 circuit 3 and an amplitude control circuit 4, wherein the driving detection circuit 2 is used to convert the charge signal representing the displacement of the driving fork fingers generated by the piezoelectric effect of the quartz tuning fork sensor 1 into a voltage signal, and output the driving detection signal 11 to the amplitude control circuit 4 and the driving signal 12 circuit 3 respectively; the driving signal 12 circuit 3 generates a driving signal 12 with the same frequency as the driving detection signal 11; the amplitude control circuit 4 generates an amplitude control signal 13 for controlling the amplitude of the driving signal 12 by comparing the amplitude of the driving detection signal 11 with a reference value.

[0025] According to an embodiment of the present invention, the drive detection circuit 2 is implemented by a charge amplifier.

[0026] According to an embodiment of the present invention, the driving signal 12 circuit 3 is implemented by a comparator.

[0027] According to one embodiment of the present invention, the demodulation and filtering circuit 7 includes a demodulator 6 and a filtering circuit 7, wherein a driving signal 12 is input to the demodulator 6, an angular velocity carrier signal 14 and an angular velocity carrier inversion signal 15 generated by the angular velocity detection circuit 5 are both input to the demodulator 6, the demodulator 6 is used to generate an angular velocity demodulation signal 16, and the angular velocity demodulation signal 16 is filtered by the filtering circuit 7 to output an angular velocity signal 17.

[0028] According to another embodiment, a quartz tuning fork gyroscope is provided. The gyroscope includes the electrostatic coupling suppression circuit described above.

[0029] The embodiment of the present invention provides a quartz tuning fork gyroscope electrostatic coupling suppression circuit, which can suppress the interference of the electrostatic error signal generated by electrostatic coupling on the angular velocity signal, thereby improving the performance of the entire meter. The following is a detailed description of a specific embodiment:

[0030] like Figure 1 As shown, an improved quartz tuning fork gyroscope orthogonal error measurement circuit is composed of a controlled object quartz tuning fork sensor 1, a drive detection circuit 2, a drive signal circuit 3, an amplitude control circuit 4, an angular velocity detection circuit 5, a demodulator 6, a filter circuit 7, an inverting circuit 8 and a compensation circuit 9.

[0031] In this embodiment, the driving detection circuit 2 is used to convert the charge signal representing the displacement of the driving fork finger generated by the piezoelectric effect of the quartz tuning fork sensor 1 into a voltage signal, which is implemented by a charge amplifier and outputs a driving detection signal 11. The amplitude control circuit 4 generates an amplitude control signal 13 for controlling the amplitude of the driving signal 12 by comparing the amplitude of the driving detection signal 11 with the reference value. The driving signal circuit 3 generates a driving signal 12 with the same frequency as the driving detection signal 11, which is implemented by a comparator, and the output amplitude of the comparator is controlled by the amplitude control signal 13; the inversion circuit 8 generates a driving inversion signal 18 with the same frequency and inversion as the driving signal 12, and the driving signal 12 and the driving inversion signal 18 are passed through the compensation circuit to generate an electrostatic coupling compensation signal 19. The electrostatic coupling compensation signal is input into the angular velocity detection circuit 5, and the electrostatic coupling error in the detection circuit is offset. The angular velocity detection circuit 5 generates an angular velocity carrier signal 14 and an angular velocity carrier inversion signal 15, and generates an angular velocity demodulation signal 16 through the demodulator 6. The angular velocity demodulation signal 16 is filtered by the filter circuit 7 and outputs an angular velocity signal 17.

[0032] Features described and / or illustrated above for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or used in place of features in other embodiments.

[0033] It should be emphasized that the term "include / comprises" when used herein refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps, components or combinations thereof.

[0034] The above method of the present invention can be implemented by hardware, or by hardware combined with software. The present invention relates to such a computer-readable program, which, when executed by a logic component, enables the logic component to implement the above-mentioned device or component, or enables the logic component to implement the above-mentioned various methods or steps. The present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, etc.

[0035] The many features and advantages of these embodiments are apparent from this detailed description, and thus the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not intended that the embodiments of the invention be limited to the exact construction and operation illustrated and described, but rather all suitable modifications and equivalents falling within the scope thereof are intended to be covered.

[0036] Parts of the present invention that are not described in detail are well known to those skilled in the art.

Claims

1. An electrostatic coupling suppression circuit for a quartz tuning fork gyroscope, characterized in that: The circuit comprises: a quartz tuning fork sensor, a driving and amplitude control circuit, an inverting circuit, a compensation circuit, an angular velocity detection circuit and a demodulation filter circuit; The output signal of the quartz tuning fork sensor refers to the driving and amplitude control circuit and the angular velocity detection circuit respectively. The driving and amplitude control circuit generates a driving signal according to the output signal of the quartz tuning fork sensor. The driving signal is also input into an inverting circuit and a demodulation and filtering circuit respectively; the inverting circuit generates a driving inverted signal with the same frequency and inverted phase according to the driving signal; the driving signal and the driving inverted signal generate an electrostatic coupling compensation signal after passing through a compensation circuit, and the signal is input into an angular velocity detection circuit to offset the electrostatic coupling error in the detection circuit; the angular velocity detection circuit generates an angular velocity carrier signal and an angular velocity carrier inverted signal, and the angular velocity signal is output after passing through a demodulation and filtering circuit.

2. The electrostatic coupling suppression circuit for a quartz tuning fork gyroscope according to claim 1, characterized in that: The driving and amplitude control circuit includes a driving detection circuit, a driving signal circuit and an amplitude control circuit. The driving detection circuit is used to convert the charge signal representing the displacement of the driving fork finger generated by the piezoelectric effect of the quartz tuning fork sensor into a voltage signal, and output the driving detection signal to the amplitude control circuit and the driving signal circuit respectively; the driving signal circuit generates a driving signal with the same frequency as the driving detection signal according to the driving detection signal; The amplitude control circuit generates an amplitude control signal for controlling the amplitude of the driving signal by comparing the amplitude of the driving detection signal with a reference value.

3. The electrostatic coupling suppression circuit for a quartz tuning fork gyroscope according to claim 2, characterized in that: The drive detection circuit is implemented using a charge amplifier.

4. An electrostatic coupling suppression circuit for a quartz tuning fork gyroscope according to claim 2 or 3, characterized in that: The driving signal circuit is implemented by using a comparator.

5. The electrostatic coupling suppression circuit for a quartz tuning fork gyroscope according to claim 1 or 2, characterized in that: The demodulation and filtering circuit includes a demodulator and a filtering circuit, wherein a driving signal is input to the demodulator, an angular velocity carrier signal and an angular velocity carrier inversion signal generated by an angular velocity detection circuit are both input to the demodulator, and the demodulator is used to generate an angular velocity demodulation signal, and the angular velocity demodulation signal is filtered by the filtering circuit and then output as an angular velocity signal.

6. A quartz tuning fork gyroscope, characterized in that: The gyroscope comprises the electrostatic coupling suppression circuit according to claims 1-5.

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