Gyroscope vibration displacement detection device and method

Abstract

The application provides a gyro vibration displacement detection device and method, which comprises generation of high-frequency bipolar square wave, modulation of gyro vibration displacement, amplification of signals and demodulation of gyro vibration displacement signals, and is implemented through corresponding circuit modules. The application modulates the gyro vibration displacement signals to a carrier frequency higher than the gyro resonance frequency, avoids the influence of circuit noise and environmental noise on the gyro displacement detection precision and the crosstalk problem of the driving signal through the parasitic capacitance, and avoids the defects of complex circuit, high cost and the like caused by the high-frequency sine wave as the carrier, has the characteristics of low implementation circuit price, less digital circuit resource occupation, simple carrier generation circuit, no need of filter for extracting the gyro vibration displacement, and is suitable for high-performance Coriolis vibration gyro and other vibration body high-precision vibration displacement detection.

Description

Technical Field

[0001] This invention belongs to the field of attitude control technology, and specifically relates to a gyroscope vibration displacement detection device and method based on high-frequency bipolar square wave modulation and demodulation, which is particularly suitable for hemispherical resonant gyroscope combinations in satellite attitude control systems and moving body inertial navigation systems. Background Technology

[0002] Existing satellite attitude control systems and inertial navigation systems for moving bodies use hemispherical resonant gyroscopes and hemispherical resonant gyroscope combinations. The detection of gyroscope vibration displacement mainly adopts the DC voltage detection method. A DC voltage is applied between the gyroscope detection electrode and the resonator. When the resonator resonates, the detection current generated by the vibration displacement flows to the front-end amplifier circuit, generating a sinusoidal detection signal with the same resonant frequency as the gyroscope. The gyroscope vibration displacement is determined by analyzing and processing the sinusoidal detection signal.

[0003] Existing DC voltage detection methods for gyroscope vibration displacement have two shortcomings: First, the resonant frequencies of most gyroscopes are distributed within the range of several kilohertz, and circuit noise and environmental noise within this frequency range will seriously affect the accuracy of gyroscope displacement detection; second, the drive signal that is consistent with the resonant frequency of the gyroscope will crosstalk to the front-end amplifier through parasitic capacitance, which will also affect the accuracy of gyroscope displacement detection. Summary of the Invention

[0004] To overcome the shortcomings of the existing technology, the inventors have conducted intensive research and provided a gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation. The gyroscope vibration displacement signal is modulated to a carrier frequency higher than the gyroscope resonant frequency, which avoids the influence of circuit noise and environmental noise on the accuracy of gyroscope displacement detection, as well as the crosstalk problem of the driving signal through parasitic capacitance. At the same time, it avoids the defects of circuit complexity and high cost caused by using high-frequency sine waves as carrier waves.

[0005] The technical solution provided by this invention is as follows:

[0006] In a first aspect, a gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation includes:

[0007] A high-frequency bipolar square wave generation circuit is used to generate a bipolar square wave with a higher frequency than the gyroscope resonant frequency, and apply it between the gyroscope detection electrode and the gyroscope resonator in the gyroscope vibration displacement modulation circuit.

[0008] The gyroscope vibration displacement modulation circuit is used to generate vibration displacement at the resonant frequency through the gyroscope resonator. By utilizing the change in capacitance between the gyroscope detection electrode and the gyroscope resonator, the gyroscope vibration displacement is modulated to the frequency of a bipolar square wave, thus obtaining the modulated gyroscope vibration displacement detection current signal.

[0009] The signal amplification circuit is used to convert the modulated gyroscope vibration displacement detection current signal from a detection current signal to a detection voltage signal, and amplify the signal.

[0010] The gyroscope vibration displacement signal demodulation circuit is used to demodulate the modulated gyroscope vibration displacement detection voltage signal from the frequency of the bipolar square wave and restore it to the gyroscope vibration displacement detection signal at the gyroscope resonant frequency, thereby completing the detection of gyroscope vibration displacement.

[0011] Secondly, a method for detecting gyroscope vibration displacement based on high-frequency bipolar square wave modulation and demodulation includes:

[0012] A bipolar square wave with a higher frequency than the gyroscope resonant frequency is generated by a high-frequency bipolar square wave generation circuit and applied between the gyroscope detection electrode and the gyroscope resonator in the gyroscope vibration displacement modulation circuit.

[0013] The gyroscope vibration displacement modulation circuit generates vibration displacement at the resonant frequency through the gyroscope resonator. By utilizing the change in capacitance between the gyroscope detection electrode and the gyroscope resonator, the gyroscope vibration displacement is modulated to the frequency of a bipolar square wave, thus obtaining the modulated gyroscope vibration displacement detection current signal.

[0014] The modulated gyroscope vibration displacement detection current signal is converted from a detection current signal to a detection voltage signal through a signal amplification circuit, and the signal is amplified.

[0015] The modulated gyroscope vibration displacement detection voltage signal is demodulated from the frequency of the bipolar square wave by the gyroscope vibration displacement signal demodulation circuit, and restored to the gyroscope vibration displacement detection signal at the gyroscope resonant frequency, thus completing the detection of gyroscope vibration displacement.

[0016] The gyroscope vibration displacement detection device and method based on high-frequency bipolar square wave modulation and demodulation provided by the present invention have the following beneficial effects:

[0017] (1) The present invention provides a gyroscope vibration displacement detection device and method based on high frequency bipolar square wave modulation and demodulation. The carrier wave is a high frequency bipolar square wave, and the required analog circuit is simple. It only needs to control the analog switch to switch between positive and negative DC voltages to apply the carrier wave. In contrast, a sine wave requires a multi-stage amplifier circuit or transformer amplification to apply the carrier wave.

[0018] (2) The present invention provides a gyroscope vibration displacement detection device and method based on high frequency bipolar square wave modulation and demodulation. The carrier is a high frequency bipolar square wave. The digital circuit occupies less resources. To achieve the same carrier frequency, the square wave only needs two states, while the sine wave requires complex logic implementation, such as the Cordic algorithm, lookup table method, etc.

[0019] (3) The present invention provides a gyroscope vibration displacement detection device and method based on high frequency bipolar square wave modulation and demodulation. The carrier is a high frequency bipolar square wave, and the required components have obvious price advantages. There are only two levels of square wave, and control can be achieved by only one output pin of FPGA. There is no need for expensive digital-to-analog converters, while high frequency sine waves require digital-to-analog converters for output.

[0020] (4) The present invention provides a gyroscope vibration displacement detection device and method based on high frequency bipolar square wave modulation and demodulation. The gyroscope vibration displacement detection signal is simple to extract and does not require a filter. The gyroscope vibration displacement detection signal can be obtained after the bipolar square wave demodulates the signal. However, the sine wave as the carrier wave requires a filter to be filtered after demodulating the signal in order to obtain the gyroscope vibration displacement signal.

[0021] (5) The present invention provides a gyroscope vibration displacement detection device and method based on high-frequency bipolar square wave modulation and demodulation, which modulates the gyroscope vibration displacement signal to a carrier frequency higher than the gyroscope resonant frequency, thereby avoiding the influence of circuit noise and environmental noise on the gyroscope displacement detection accuracy and the crosstalk problem of the driving signal through parasitic capacitance, thus improving the gyroscope vibration displacement detection accuracy. Attached Figure Description

[0022] Figure 1 This is a block diagram of a gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to the present invention.

[0023] Figure 2 This is a block diagram showing the specific implementation of each module circuit of the gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to the present invention. Detailed Implementation

[0024] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0025] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0026] This invention provides a gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation, such as... Figure 1 As shown, it includes:

[0027] A high-frequency bipolar square wave generating circuit 1 is used to generate a bipolar square wave with a frequency higher than the gyroscope resonant frequency (e.g., 10 times or more), and apply it between the gyroscope detection electrode 12 and the gyroscope resonator 11 of the gyroscope vibration displacement modulation circuit 2.

[0028] The gyroscope vibration displacement modulation circuit 2 is used to generate vibration displacement at the resonant frequency through the gyroscope resonator 11. By utilizing the change in capacitance between the gyroscope detection electrode 12 and the gyroscope resonator 11, the gyroscope vibration displacement is modulated to the frequency of a high-frequency bipolar square wave, thereby obtaining the modulated gyroscope vibration displacement detection current signal 13 and completing the gyroscope vibration displacement modulation 2.

[0029] The signal amplification circuit 3 is used to convert the modulated gyroscope vibration displacement detection current signal 13 from a detection current signal into a detection voltage signal and amplify the signal.

[0030] The gyroscope vibration displacement signal demodulation circuit 4 is used to demodulate the modulated gyroscope vibration displacement detection voltage signal from the frequency of the bipolar square wave and restore it to the gyroscope vibration displacement detection signal 15 at the gyroscope resonant frequency, thus completing the detection of gyroscope vibration displacement and providing an important vibration displacement detection signal for the subsequent gyroscope control system.

[0031] Figure 2 This is a block diagram illustrating the specific implementation of each module circuit of a gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation. The high-frequency bipolar square wave generation circuit 1 uses digital circuit 5 (including but not limited to FPGA) to generate a switch control signal 6. This switch control signal 6 controls an analog switch 9 to switch the voltage between the gyroscope detection electrode 12 and the gyroscope resonator 11 between two DC voltages (7 and 8), generating a high-frequency bipolar square wave. The amplitudes of the two DC voltages (7 and 8) can be set to be equal; if the amplitudes are not equal, the gain of the gyroscope vibration displacement detection signal 15 is adjusted in the subsequent gyroscope vibration displacement signal modulation circuit 4 to restore it to a continuous sinusoidal signal. The gain adjustment switching frequency is the carrier frequency of the high-frequency bipolar square wave 10.

[0032] Gyroscope vibration displacement modulation involves applying a high-frequency bipolar square wave 10 between the gyroscope detection electrode 12 and the gyroscope resonator 11. The gyroscope resonator 11 generates a vibration displacement at its resonant frequency. By changing the capacitance between the gyroscope detection electrode 12 and the gyroscope resonator 11, the gyroscope vibration displacement is modulated to the frequency of the high-frequency bipolar square wave 10, resulting in a modulated gyroscope vibration displacement detection current signal 13. The positions of the gyroscope detection electrode 12 and the gyroscope resonator 11 can be interchanged.

[0033] The signal amplification circuit 3 uses a front-end amplifier circuit to convert the modulated gyroscope vibration displacement detection current signal 13 from a detection current signal to a detection voltage signal, and then amplifies the signal.

[0034] The gyroscope vibration displacement signal demodulation circuit 4 controls the demodulation switch 14 based on the switch control signal 6 that generates a high-frequency bipolar square wave 10, thereby demodulating the amplified modulated gyroscope vibration displacement detection voltage signal. The switch control signal 6 has two levels: high and low. It can maintain the modulated gyroscope vibration displacement detection voltage signal unchanged when at a high level and invert it when at a low level to complete demodulation; or it can invert the modulated gyroscope vibration displacement detection voltage signal when at a high level and maintain it unchanged when at a low level to complete demodulation, outputting the gyroscope vibration displacement detection signal 15, ultimately completing the detection of the gyroscope vibration displacement.

[0035] Accordingly, the present invention also provides a method for detecting gyroscope vibration displacement based on high-frequency bipolar square wave modulation and demodulation, comprising:

[0036] A bipolar square wave with a higher frequency than the gyroscope resonant frequency is generated by the high-frequency bipolar square wave generation circuit 1 and applied between the gyroscope detection electrode 12 and the gyroscope resonator 11 of the gyroscope vibration displacement modulation circuit 2.

[0037] The gyroscope vibration displacement modulation circuit 2 generates vibration displacement at the resonant frequency through the gyroscope resonator 11. By utilizing the change in capacitance between the gyroscope detection electrode 12 and the gyroscope resonator 11, the gyroscope vibration displacement is modulated to the frequency of a bipolar square wave, thereby obtaining the modulated gyroscope vibration displacement detection current signal 13, thus completing the gyroscope vibration displacement modulation 2.

[0038] The modulated gyroscope vibration displacement detection current signal 13 is converted from a detection current signal to a detection voltage signal by the signal amplification circuit 3, and the signal is amplified.

[0039] The gyroscope vibration displacement signal demodulation circuit 4 demodulates the modulated gyroscope vibration displacement detection voltage signal from the frequency of the bipolar square wave, restoring it to the gyroscope vibration displacement detection signal 15 at the gyroscope resonant frequency, thus completing the detection of gyroscope vibration displacement and providing an important vibration displacement detection signal for the subsequent gyroscope control system.

[0040] The structure and function of the high-frequency bipolar square wave generating circuit 1, the gyroscope vibration displacement modulation circuit 2, the signal amplification circuit 3, and the gyroscope vibration displacement signal demodulation circuit 4 are consistent with the corresponding structures and functions in the first aspect, and will not be repeated here.

[0041] The device and method of this invention can be applied to the vibration displacement detection of Coriolis gyroscopes, but the vibration displacement of other vibrating bodies (resonators) can also be detected using this device and method.

[0042] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0043] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation, characterized in that, include: A high-frequency bipolar square wave generating circuit (1) is used to generate a bipolar square wave with a higher frequency than the gyroscope resonant frequency and apply it between the gyroscope detection electrode (12) and the gyroscope resonator (11) of the gyroscope vibration displacement modulation circuit (2). The gyroscope vibration displacement modulation circuit (2) is used to generate vibration displacement at the resonant frequency through the gyroscope resonator (11). By utilizing the change in capacitance between the gyroscope detection electrode (12) and the gyroscope resonator (11), the gyroscope vibration displacement is modulated to the frequency of the bipolar square wave, and the modulated gyroscope vibration displacement detection current signal is obtained. The signal amplification circuit (3) is used to convert the modulated gyroscope vibration displacement detection current signal from the detection current signal to the detection voltage signal and amplify the signal. The gyroscope vibration displacement signal demodulation circuit (4) is used to demodulate the modulated gyroscope vibration displacement detection voltage signal from the frequency of the bipolar square wave and restore it to the gyroscope vibration displacement detection signal at the gyroscope resonant frequency, thereby completing the detection of gyroscope vibration displacement.

2. The gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation according to claim 1, characterized in that, The high-frequency bipolar square wave generating circuit (1) includes a digital circuit (5) and an analog switch (9). The digital circuit (5) generates a switch control signal, which controls the analog switch (9) to switch the voltage between the gyroscope detection electrode (12) and the gyroscope resonator (11) between positive and negative DC voltages, thereby generating a bipolar square wave with a higher frequency than the gyroscope resonant frequency.

3. The gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation according to claim 2, characterized in that, The amplitudes of the positive and negative DC voltages may be equal or unequal.

4. The gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation according to claim 1, characterized in that, The signal amplification circuit (3) uses a front-end amplifier circuit to convert the modulated gyroscope vibration displacement detection current signal from a detection current signal to a detection voltage signal and amplifies the signal.

5. The gyroscope vibration displacement detection device based on high-frequency bipolar square wave modulation and demodulation according to claim 1, characterized in that, The gyroscope vibration displacement signal demodulation circuit (4) controls the demodulation switch (14) according to the switch control signal that generates a bipolar square wave to demodulate the amplified modulated gyroscope vibration displacement detection voltage signal. The switch control signal has two levels: high and low. When the signal is high, the modulated gyroscope vibration displacement detection voltage signal remains unchanged. When the signal is low, the modulated gyroscope vibration displacement detection voltage signal is inverted to complete the demodulation. Alternatively, the modulated gyroscope vibration displacement detection voltage signal can be inverted when the signal is high and kept unchanged when the signal is low to complete the demodulation. The gyroscope vibration displacement detection signal is then output to perform gyroscope vibration displacement detection.

6. A method for detecting gyroscope vibration displacement based on high-frequency bipolar square wave modulation and demodulation, characterized in that, include: A bipolar square wave with a higher frequency than the gyroscope resonant frequency is generated by a high-frequency bipolar square wave generation circuit and applied between the gyroscope detection electrode and the gyroscope resonator in the gyroscope vibration displacement modulation circuit. The gyroscope vibration displacement modulation circuit generates vibration displacement at the resonant frequency through the gyroscope resonator. By utilizing the change in capacitance between the gyroscope detection electrode and the gyroscope resonator, the gyroscope vibration displacement is modulated to the frequency of a bipolar square wave, thus obtaining the modulated gyroscope vibration displacement detection current signal. The modulated gyroscope vibration displacement detection current signal is converted from a detection current signal to a detection voltage signal through a signal amplification circuit, and the signal is amplified. The modulated gyroscope vibration displacement detection voltage signal is demodulated from the frequency of the bipolar square wave by the gyroscope vibration displacement signal demodulation circuit, and restored to the gyroscope vibration displacement detection signal at the gyroscope resonant frequency, thus completing the detection of gyroscope vibration displacement.

7. The gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to claim 6, characterized in that, In the step of generating a bipolar square wave with a higher frequency than the gyroscope resonant frequency through a high-frequency bipolar square wave generating circuit, the high-frequency bipolar square wave generating circuit uses a digital circuit to generate a switch control signal. The switch control signal controls an analog switch to switch the voltage between the gyroscope detection electrode and the gyroscope resonator between positive and negative DC voltages, thereby generating a bipolar square wave with a higher frequency than the gyroscope resonant frequency.

8. The gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to claim 7, characterized in that, The amplitudes of the positive and negative DC voltages may be equal or unequal.

9. The gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to claim 6, characterized in that, The signal amplification circuit uses a front-end amplifier circuit to convert the modulated gyroscope vibration displacement detection current signal from a detection current signal to a detection voltage signal, and then amplifies the signal.

10. The gyroscope vibration displacement detection method based on high-frequency bipolar square wave modulation and demodulation according to claim 6, characterized in that, The gyroscope vibration displacement signal demodulation circuit controls the demodulation switch according to the switch control signal that generates a bipolar square wave, and demodulates the amplified modulated gyroscope vibration displacement detection voltage signal. The switch control signal has two levels: high and low. When the signal is high, the modulated gyroscope vibration displacement detection voltage signal remains unchanged; when the signal is low, the signal is inverted to complete demodulation. Alternatively, the signal can be inverted when the signal is high and kept unchanged when the signal is low to complete demodulation, and the gyroscope vibration displacement detection signal is output to detect the gyroscope vibration displacement.

Images