Quartz gyroscope circuit

Abstract

This invention provides a quartz gyroscope circuit, including a closed-loop drive circuit. The closed-loop drive circuit includes a drive interdigitator, a drive terminal circuit, and a controller. The drive terminal circuit converts the drive response charge signal generated by the drive interdigitator into a drive response voltage signal and transmits the drive response voltage signal to the controller. The controller generates an original digital reference signal, adjusts the frequency and amplitude of the original digital reference signal based on the drive response voltage signal to generate a drive voltage signal, and transmits the drive voltage signal to the drive terminal circuit. The drive terminal circuit amplifies the drive voltage signal and applies the amplified drive voltage signal to the drive interdigitator so that the oscillation frequency of the drive interdigitator is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive interdigitator is within a preset amplitude range. This invention addresses the shortcomings of existing analog quartz gyroscopes, where the oscillation frequency cannot operate at the resonant frequency and the oscillation amplitude is unstable.

Description

Technical Field

[0001] This invention relates to the field of gyroscope technology, and more particularly to a quartz gyroscope circuit. Background Technology

[0002] A gyroscope is an important inertial sensing device used to measure angular velocity or angular displacement. Based on their working principle or structure, gyroscopes can be broadly classified into three categories: mechanical gyroscopes, optical gyroscopes, and micro-electro-mechanical system (MEMS) gyroscopes. Compared to other traditional gyroscopes, MEMS gyroscopes are characterized by their small size, light weight, low power consumption, and high reliability, and are widely used in aerospace, automotive, marine, and guidance systems. A quartz gyroscope is a type of MEMS gyroscope based on the Coriolis force principle, using a quartz crystal as its sensing element. Quartz material has excellent piezoelectric properties, so quartz gyroscopes do not require complex structures for control and detection. Furthermore, quartz gyroscopes offer advantages such as low cost and high quality factor.

[0003] In existing technologies, quartz gyroscopes often employ fully analog circuits to achieve oscillation control and external angular velocity detection. These fully analog circuits utilize multiple discrete components, which are often non-ideal in practical engineering applications, introducing zero-point errors in angular velocity. Furthermore, the parameters of these discrete components differ, as do the parameters of the quartz tuning fork. Consequently, the drive circuit cannot guarantee that the quartz tuning fork drive end will always operate at its resonant frequency, and the oscillation amplitude varies significantly, resulting in instability. Summary of the Invention

[0004] This invention provides a quartz gyroscope circuit to solve the defects of existing analog quartz gyroscopes, which cannot operate at the resonant frequency and have unstable oscillation amplitude.

[0005] This invention provides a quartz gyroscope circuit, including a closed-loop drive circuit. The closed-loop drive circuit includes a drive fork, a drive terminal circuit, and a controller, wherein the drive fork refers to the drive terminal of a quartz tuning fork. The drive terminal circuit is used to convert the drive response charge signal generated by the drive fork into a drive response voltage signal and transmit the drive response voltage signal to the controller. The controller is used to generate an original digital reference signal, adjust the frequency and amplitude of the original digital reference signal based on the drive response voltage signal to generate a drive voltage signal, and transmit the drive voltage signal to the drive terminal circuit. The drive terminal circuit is used to amplify the drive voltage signal and apply the amplified drive voltage signal to the drive fork so that the oscillation frequency of the drive fork is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive fork is within a preset amplitude range.

[0006] According to the present invention, a quartz gyroscope circuit further includes a detection circuit; the detection circuit includes a detection fork, a detection terminal circuit, and a controller, wherein the detection fork refers to the detection terminal of the quartz tuning fork; the detection terminal circuit is used to convert the detection response charge signal generated by the detection fork into a detection response voltage signal, and transmit the detection response voltage signal to the controller; the controller is used to analyze the detection response voltage signal to obtain angular velocity information.

[0007] According to a quartz gyroscope circuit provided by the present invention, the controller includes a first analog-to-digital converter (ADC) and a digital-to-analog converter (DAC); the driving terminal circuit is used to transmit the driving response voltage signal to the first ADC; the first ADC is used to convert the driving response voltage signal into a driving response digital signal; the controller is used to adjust the frequency and amplitude of the original digital reference signal based on the driving response digital signal to generate a digital excitation signal, and transmit the digital excitation signal to the DAC; the DAC is used to convert the digital excitation signal into the driving voltage signal.

[0008] According to a quartz gyroscope circuit provided by the present invention, the controller includes a digitally controlled oscillator; the original digital reference signal includes an original sine digital signal and an original cosine digital signal; the digitally controlled oscillator is used to generate the original sine digital signal and the original cosine digital signal; the controller is used to demodulate the drive response digital signal based on the original sine digital signal to generate an original in-phase component, and to demodulate the drive response signal based on the original cosine digital signal to generate an original quadrature component; the controller is used to calculate the response amplitude of the drive response digital signal based on the original in-phase component and the original quadrature component, and to determine the excitation amplitude of the digital excitation signal based on the response amplitude and a preset target amplitude; the controller is used to calculate the response phase of the drive response digital signal based on the original in-phase component and the original quadrature component, and to determine the excitation phase of the digital excitation signal based on the response phase and a preset target phase.

[0009] According to a quartz gyroscope circuit provided by the present invention, the controller further includes an automatic gain control module; the digitally controlled oscillator is used to generate the original sine digital signal and the original cosine digital signal based on the excitation frequency, wherein the phase of the original sine digital signal is the target phase; the automatic gain control module is used to generate the digital excitation signal based on the original sine digital signal and the excitation amplitude, wherein the amplitude of the digital excitation signal is the target amplitude.

[0010] According to a quartz gyroscope circuit provided by the present invention, the controller is used to perform phase compensation on the original in-phase component based on the resonant frequency, and to perform phase compensation on the original quadrature component based on the resonant frequency.

[0011] According to a quartz gyroscope circuit provided by the present invention, the controller is used to perform capacitive compensation on the original quadrature components after phase compensation based on the quadrature component compensation value, wherein the quadrature component compensation value is obtained based on the capacitive performance of the quartz tuning fork.

[0012] According to a quartz gyroscope circuit provided by the present invention, the controller includes a second analog-to-digital converter; the detection terminal circuit is used to transmit the detection response voltage signal to the second analog-to-digital converter; the second analog-to-digital converter is used to convert the detection response voltage signal into a detection response digital signal; the controller is used to parse the detection response digital signal to obtain the angular velocity information.

[0013] According to a quartz gyroscope circuit provided by the present invention, the controller includes a digitally controlled oscillator; the original digital reference signal includes an original sine digital signal and an original cosine digital signal; the digitally controlled oscillator is used to generate the original sine digital signal and the original cosine digital signal; the controller is used to demodulate the detection response digital signal based on the original sine digital signal to generate a detection in-phase component, and to demodulate the detection response digital signal based on the original cosine digital signal to generate a detection quadrature component.

[0014] According to a quartz gyroscope circuit provided by the present invention, the controller is used to perform phase compensation on the detected co-directional component and phase compensation on the detected quadrature component; the controller is also used to perform temperature compensation on the detected co-directional component based on the real-time ambient temperature.

[0015] The quartz gyroscope circuit provided by this invention includes a closed-loop drive circuit. The closed-loop drive circuit includes a drive fork, a drive-end circuit, and a controller. The drive fork refers to the drive end of a quartz tuning fork. The drive-end circuit converts the drive response charge signal generated by the drive fork into a drive response voltage signal and transmits the drive response voltage signal to the controller. The controller generates an original digital reference signal, adjusts the frequency and amplitude of the original digital reference signal based on the drive response voltage signal to generate a drive voltage signal, and transmits the drive voltage signal to the drive-end circuit. The drive-end circuit amplifies the drive voltage signal and applies the amplified drive voltage signal to the drive fork so that the oscillation frequency of the drive fork is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive fork is within a preset amplitude range. In the above process, the frequency and amplitude of the original digital reference signal are adjusted by the drive response voltage signal fed back during the oscillation of the drive fork to generate the drive voltage signal. An amplified driving voltage signal is used to excite the driving fork finger, so that the oscillation frequency of the driving fork finger is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the driving fork finger is within the preset amplitude range, thereby ensuring the stability of the oscillation frequency and the stability of the oscillation amplitude of the driving fork finger. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structural connection of the quartz gyroscope circuit provided by the present invention;

[0018] Figure 2 This is the equivalent circuit model for driving interdigital fingers provided by the present invention;

[0019] Figure 3 This is a schematic diagram of the closed-loop drive circuit provided by the present invention;

[0020] Figure 4 This is a schematic diagram of the detection circuit principle provided by the present invention;

[0021] Figure 5 This is a schematic diagram of the measured data of the original co-directional and original quadrature components of the digital quartz gyroscope driver provided by the present invention;

[0022] Figure 6 This is a schematic diagram of the measured data of the same-direction component and the quadrature component after compensation of the digital quartz gyroscope driver end provided by the present invention.

[0023] Figure 7 This is a schematic diagram of the room temperature static test data of the digital quartz gyroscope provided by the present invention;

[0024] Figure 8 This is a physical example diagram of the digital quartz gyroscope provided by the present invention;

[0025] Figure 9 This is a schematic diagram of the zero-position data of the temperature cycling test of the digital quartz gyroscope provided by the present invention;

[0026] Figure 10 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the embodiments of the present invention.

[0028] A fully analog quartz gyroscope uses discrete components to achieve closed-loop control and external angular velocity detection. The quartz gyroscope circuit mainly consists of two parts: a drive circuit and a detection circuit. The drive circuit typically employs a self-excited oscillation closed-loop drive scheme to track the quartz resonant frequency, ensuring that the quartz drive end oscillates at the resonant frequency point. This guarantees that even if the natural frequency of the quartz drive end drifts, it will still maintain resonance at the new frequency point. Furthermore, the drive circuit incorporates an automatic gain control (AGC) feedback control circuit into the self-excited oscillation circuit, keeping the amplitude of the drive signal constant or controlling its variation within a certain range, thereby ensuring the stability of the drive signal's frequency and amplitude.

[0029] The detection circuit converts the charge signal of angular velocity into a voltage output signal. Its working process is as follows: When there is an external angular velocity input, the quartz tuning fork generates a charge signal. The charge / voltage conversion circuit (also known as the Q / V conversion circuit) and amplification circuit of the detection circuit convert the charge signal into a voltage signal. Using a drive signal with the same frequency as the voltage signal as a reference signal, the signal is demodulated by a multiplier (usually a switching multiplier) and a low-pass filter circuit to obtain the same-direction component at the detection end (this same-direction component is used to represent angular velocity information). The detection circuit finally outputs a DC voltage signal corresponding to the angular velocity.

[0030] When using discrete components to build the drive and detection circuits for angular velocity measurement, fully analog quartz gyroscopes have several drawbacks: First, the discrete components used are non-ideal, so factors such as the DC bias of the operational amplifier and the injected charge of the switching multiplier introduce zero-point errors in angular velocity. Second, fully analog quartz gyroscopes can only demodulate the same-direction component at the detection end, not the quadrature component, and cannot obtain information such as drive frequency and AGC, thus failing to provide data for subsequent gyroscope improvements and quartz watch movement adjustments. Third, there are differences in the parameters of independent components, and even differences in the parameters of the quartz tuning fork, so the drive circuit cannot guarantee that the quartz tuning fork drive end will always operate at its resonant frequency, resulting in a certain phase angle deviation. Fourth, fully analog quartz gyroscopes have poor compensability, and batch compensation is difficult.

[0031] Based on the above analysis, this invention provides a quartz gyroscope circuit. The following is in conjunction with... Figures 1-9 This invention describes a quartz gyroscope circuit according to an embodiment of the present invention.

[0032] In one embodiment, such as Figure 1As shown, the quartz gyroscope circuit includes a closed-loop drive circuit; the closed-loop drive circuit includes a drive fork, a drive-end circuit, and a controller, wherein the drive fork refers to the drive end of the quartz tuning fork; the drive-end circuit is used to convert the drive response charge signal generated by the drive fork into a drive response voltage signal, and transmit the drive response voltage signal to the controller; the controller is used to generate an original digital reference signal, adjust the frequency and amplitude of the original digital reference signal based on the drive response voltage signal, generate a drive voltage signal, and transmit the drive voltage signal to the drive-end circuit; the drive-end circuit is used to amplify the drive voltage signal, and apply the amplified drive voltage signal to the drive fork so that the oscillation frequency of the drive fork is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive fork is within a preset amplitude range.

[0033] In this embodiment, the quartz gyroscope includes a quartz tuning fork, which is a sensitive element. The quartz tuning fork includes a driving end and a sensing end; the driving end is called the driving fork finger, and the sensing end is called the sensing fork finger. The controller is a component capable of digital information processing, such as a microcontroller. The driving tuning fork, the driving end circuit, and the controller realize closed-loop tracking control of the resonant frequency of the quartz tuning fork. By adjusting the frequency and amplitude of the original digital reference signal through the driving response digital signal, a driving voltage signal is finally generated. The amplified driving voltage signal excites the driving fork finger to oscillate at the resonant frequency of the quartz tuning fork, so as to ensure that the frequency and amplitude of the driving tuning fork are relatively stable during oscillation. In this embodiment, the preset amplitude range is a range of amplitude variation set according to the gyroscope hardware parameters, ambient temperature, and other factors. This preset amplitude range is a relatively small range of variation. When the oscillation amplitude of the driving fork finger varies within this preset amplitude range, it can be determined that the oscillation amplitude of the driving fork finger is relatively stable.

[0034] In one embodiment, the quartz gyroscope circuit further includes a detection circuit; the detection circuit includes a detection fork, a detection end circuit, and a controller, wherein the detection fork refers to the detection end of the quartz tuning fork; the detection end circuit is used to convert the detection response charge signal generated by the detection fork into a detection response voltage signal, and transmit the detection response voltage signal to the controller; the controller is used to analyze the detection response voltage signal to obtain angular velocity information.

[0035] In this embodiment, the detection circuit is used to detect the charge signal generated by the displacement of the interdigital fingers, i.e., the detection response charge signal, and converts the detection response charge signal into a detection response voltage signal. The controller is responsible for processing the detection response voltage signal into angular velocity information.

[0036] In one embodiment, the controller includes a first analog-to-digital converter (ADC) and a digital-to-analog converter (DAC); the driving circuit is configured to transmit a driving response voltage signal to the first ADC; the first ADC is configured to convert the driving response voltage signal into a driving response digital signal; the controller is configured to adjust the frequency and amplitude of the original digital reference signal based on the driving response digital signal to generate a digital excitation signal, and transmit the digital excitation signal to the DAC; the DAC is configured to convert the digital excitation signal into a driving voltage signal.

[0037] In this embodiment, the drive response voltage signal of the driving interphalange is sampled by a first analog-to-digital converter (ADC) to generate a digital drive response signal, which facilitates the controller's digital processing of the drive response signal (i.e., the digitized drive response digital signal). Simultaneously, a digital-to-analog converter (DAC) converts the digital excitation signal generated by the controller into a drive voltage signal. This drive voltage signal is an analog signal, which can be applied to the driving interphalange to excite its oscillation. The digital processing is easy to implement and can be more easily integrated into a smaller chip, thus reducing the overall size of the quartz gyroscope. It also reduces the use of analog components, thereby avoiding errors caused by analog components and improving the stability of the frequency and amplitude of the quartz tuning fork oscillation.

[0038] In this embodiment, the driving circuit includes a driving preamplifier and a voltage amplification module. The driving preamplifier is used to detect the driving response charge signal generated by the driving interdigital finger, convert the driving response charge signal into a driving response voltage signal, and transmit the driving response voltage signal to the controller. The controller is used to transmit the driving voltage signal to the voltage amplification module. The voltage amplification module is used to amplify the driving voltage signal and apply the amplified driving voltage signal to the driving interdigital finger.

[0039] In this embodiment, the driver preamplifier (hereinafter referred to as the driver preamplifier) ​​is a Q / V conversion circuit designed with a precision operational amplifier as the core component. It converts the detected response charge signal into a drive response voltage signal without distortion. Then, the first ADC converts the drive response voltage signal into a drive response digital signal that can be processed by the controller. After further processing of the drive response digital signal, the controller generates a digital excitation signal and transmits it to the DAC. The DAC converts the digital excitation signal into a drive voltage signal. The DAC transmits the drive voltage signal to the voltage amplification module, which amplifies the voltage drive signal to enhance the signal strength and applies the amplified voltage drive signal to the drive interdigital fingers to excite the drive interdigital fingers to oscillate.

[0040] In one embodiment, the controller includes a digitally controlled oscillator; the original digital reference signal includes an original sine digital signal and an original cosine digital signal.

[0041] The digitally controlled oscillator is used to generate the original sine digital signal and the original cosine digital signal; the controller is used to demodulate the drive response digital signal based on the original sine digital signal to generate the original in-phase component, and to demodulate the drive response signal based on the original cosine digital signal to generate the original quadrature component; the controller is used to calculate the response amplitude of the drive response digital signal based on the original in-phase component and the original quadrature component, and to determine the excitation amplitude of the digital excitation signal based on the response amplitude and a preset target amplitude; the controller is used to calculate the response phase of the drive response digital signal based on the original in-phase component and the original quadrature component, and to determine the frequency of the digital excitation signal based on the response phase and a preset target phase.

[0042] In this embodiment, the dual-channel sinusoidal digital drive signal with controllable output frequency from the digitally controlled oscillator (NCO) serves as the reference signal. This reference signal is demodulated in the same direction to obtain the original sinusoidal digital signal; then, it is demodulated in quadrature to obtain the original cosine digital signal. The initial phase of the original sinusoidal digital signal (in the same direction) and the original cosine digital signal (quadrature) generated by the NCO is 0.

[0043] In one embodiment, the controller further includes an automatic gain control module; the digitally controlled oscillator is configured to generate a raw sine digital signal and a raw cosine digital signal based on the excitation frequency, wherein the phase of the raw sine digital signal is a target phase; the automatic gain control module is configured to generate a digital excitation signal based on the raw sine digital signal and the excitation amplitude, wherein the amplitude of the digital excitation signal is a target amplitude.

[0044] In this embodiment, a digital phase-locked loop (PLL) is formed based on the closed-loop control circuit and the controller, locking the excitation signal and response signal of the driving fork finger to a certain phase. The frequency corresponding to this phase is the resonant frequency of the quartz tuning fork, that is, the frequency control of the driving voltage signal is achieved by phase locking.

[0045] In one embodiment, the controller is configured to perform phase compensation on the original in-phase component based on the resonant frequency, and to perform phase compensation on the original quadrature component based on the resonant frequency.

[0046] In this embodiment, the equivalent circuit model for driving the interdigitated fingers is as follows: Figure 2As shown, R1 represents the equivalent resistance, L1 represents the equivalent inductance, and C1 represents the series equivalent capacitance. R1, L1, and C1 form an RLC branch. C0 represents the equivalent parallel static capacitance. s Indicates the response of the RLC branch, i C0 i represents the response of branch C0, and i represents the total response.

[0047] Throughout the entire temperature range, since the relative change of resistance R1 is much greater than the relative change of capacitance C0, the phase of the total current flowing through the driving fork is not exactly the same at the resonant frequency point, but has a slight difference. This results in a large deviation between the frequency of the excitation signal generated by the NCO and the actual resonant frequency of the driving tuning fork.

[0048] In the closed-loop drive circuit, processes such as driving the preamplifier frequency response and ADC conversion time introduce delays to the controller program execution time. Therefore, a phase difference exists between the drive response digital signal and the original digital reference signal, leading to coupling between the original sinusoidal and cosine digital signals. Phase compensation can be performed on the original sinusoidal and cosine digital signals. The calculated optimal compensation phase angle at the drive end indicates that, under this angle, the RLC series branch at the resonant frequency is purely resistive. The in-phase and quadrature components at the drive end are contributed by the equivalent resistance R1 and static capacitance C0 in the equivalent circuit model, respectively.

[0049] Furthermore, the ideal phase compensation principle is as follows:

[0050] In an ideal state, that is, without considering the delay caused by the program and hardware, the excitation signal F generated by the NCO without phase compensation is set. x (t) (at which point the excitation signal frequency is not necessarily the resonant frequency) is:

[0051] F x (t)=F d *sin(wt) (1);

[0052] Among them, F d t is the amplitude, w is the time, and w is the phase.

[0053] Setting F sin (t) is the original sinusoidal digital signal, F cos (t) is the original cosine digital signal with amplitude F. jt The values ​​are constants, as follows:

[0054] F sin (t)=F jt *sin(wt) (2);

[0055] F cos (t)=Fjt *cos(wt) (3);

[0056] Based on such Figure 2 The equivalent circuit model of the driving interdigit is shown. Based on the frequency response of the RLC series branch, the phase shift corresponding to w in the phase frequency characteristic is θ. RLC When w equals the series resonant frequency w d When, θ RLC It equals 0°.

[0057] Set RLC branch response i S The amplitude of (t) is F s Then the response i of the RLC series branch S (t) is:

[0058] i S (t)=F s *sin(wt+θ RLC (4);

[0059] Let the response of branch C0 be i C0 The amplitude of (t) is F c0 Then the response i of the electrostatic capacitance C0 branch C0 for:

[0060] i C0 (t)=F c0 *cos(wt) (5);

[0061] Then the total response signal i(t) driving the interdigital fingers is:

[0062] i(t) = i S (t)+i C0 (t) (6);

[0063]

[0064] In the formula, The phase difference between the excitation signal and the response signal is specifically:

[0065]

[0066] In an ideal state, This is mainly caused by the frequency response of the quartz gyroscope instrument core itself.

[0067] Using the superposition principle, respectively for i S (t) and i C0 (t) is used for demodulation. S The same-direction component Sin(t) is Orthogonal components Cos is (After multiplication demodulation and filtering) is shown below:

[0068] Sin is =F jt *F s *0.5*cos(θ RLC (9);

[0069] Cos is =F jt *F s *0.5*sin(θ RLC (10);

[0070] Similarly, i C0 Sini (t) in the same direction c0 Orthogonal components Cosi c0 As shown below:

[0071] Sin ic0 =0 (11);

[0072] Cos ic0 =F jt *F c0 *0.5 (12);

[0073] The demodulated co-directional component A (the real part of the complex number, i.e., the original sine digital signal) and quadrature component B (the imaginary part of the complex number, i.e., the original cosine digital signal) are respectively:

[0074] A = F jt *F s *0.5*cos(θ RLC (13);

[0075] B = F jt *F s *0.5*sin(θ RLC )+F jt *F c0 *0.5 (14);

[0076] Ideally, the static capacitance C1 in the RLC branch only contributes a quadrature component. Furthermore, when the frequency w of the excitation signal is the series resonant frequency, Cos... is If the value is 0, then at this time, the original sinusoidal digital signal (the real part of the complex number) is contributed only by the equivalent resistance R1, and the original cosine digital signal (the imaginary part of the complex number) is contributed only by the electrostatic capacitance C0.

[0077] The amplitude Amp of the demodulated response signal is:

[0078]

[0079]

[0080] Phase F of the demodulated response signal θ for:

[0081]

[0082]

[0083] Therefore, it can be seen that the amplitude and initial phase of the response signal can be calculated based on the demodulated co-directional and quadrature components.

[0084] Based on the above, further considering the phase compensation principle under the delayed phase angle, it is as follows:

[0085] Considering the delay phase angle caused by the program and hardware, and assuming the delay phase angle is Δθ, the excitation signal F x (t), the original sinusoidal digital signal F sin (t) and the original cosine digital signal F cos If (t) remains unchanged, then i S (t) is:

[0086] i S (t)=F s *sin(wt+θ RLC +Δθ) (19);

[0087] i C0 for:

[0088] i C0 (t)=F c0 *cos(wt+Δθ) (20);

[0089] In the non-ideal case, the total response signal i(t) of the driving interdigit is:

[0090] i(t) = i S (t)+i C0 (t) (21);

[0091]

[0092] i S The same-direction component Sin(t) is Orthogonal components Cos is (After multiplication demodulation and filtering) is shown below:

[0093] Sin is =F jt *F s *0.5*cos(θ RLC +Δθ) (23);

[0094] Cos is =Fjt *F s *0.5*sin(θ RLC +Δθ) (24);

[0095] i C0 Sini (t) in the same direction c0 Orthogonal components Cosi c0 As shown below:

[0096] Sin ic0 =-F jt *F c0 *0.5*sin(Δθ) (25);

[0097] Cos ic0 =F jt *F c0 *0.5*sin(Δθ) (26);

[0098] The same-direction component A is: and the orthogonal components B are:

[0099] A = F jt *F s *0.5*cos(θ RLC +Δθ)-F jt *F c0 *0.5*sin(Δθ) (27);

[0101] B = F jt *F s *0.5*sin(θ RLC +Δθ)+F jt *F c0 *0.5*cos(Δθ) (28);

[0103] The amplitude Amp of the demodulated response signal is:

[0104]

[0105]

[0106] When w is the series resonant frequency, θ RLC =0°, because the delay phase angle Δθ exists, the equivalent resistance R1 and the static capacitance C0 will both contribute the same-direction component and the quadrature component.

[0107] Phase angle compensation is performed on the same-direction component A:

[0108] A new =A*cos(Δθ)+B*sin(Δθ) (31);

[0109] A new =F jt *F s *0.5*cos(θ RLC (32);

[0110] Phase angle compensation is performed on the orthogonal component B:

[0111] B mew =B*cos(Δθ)-A*sin(Δθ) (33);

[0112] B mew =F jt *F s *0.5*sin(θ RLC )+F jt *F c0 *0.5 (34);

[0113] A new and B new It is consistent with the in-phase component A and the quadrature component B under ideal conditions, thus achieving the purpose of phase compensation.

[0114] In this embodiment, during the phase compensation (also known as angle compensation) process, compensation can also be performed based on the real-time ambient temperature.

[0115] In one embodiment, the controller is configured to perform capacitive compensation on the original quadrature components after phase compensation based on the quadrature component compensation value, wherein the quadrature component compensation value is obtained based on the capacitive properties of the quartz tuning fork.

[0116] In this embodiment, based on the original quadrature components after phase compensation, a quadrature component compensation value proportional to C0 can be obtained. Subtracting this quadrature component compensation value from the original quadrature components after phase compensation, if the target phase is 0, then the quadrature component of the driving end after phase angle compensation and C0 coefficient compensation is 0.

[0117] By performing phase compensation and capacitive compensation on the original co-directional and original quadrature components, it can be ensured that the phase difference between the excitation signal and the response signal driving the interdigital fork is always 0° throughout the entire temperature range, and that the frequency of the analog driving signal generated by the NCO is stable at the resonant frequency of the quartz tuning fork.

[0118] Based on the above embodiments, the response phase of the interdigital drive response digital signal can be calculated from the compensated original co-directional component and the original quadrature component. The difference between this phase and the target phase is then calculated. A pre-set frequency control algorithm determines the frequency of the NCO output digital excitation signal based on this phase difference; this process constitutes a phase loop. Taking the modulus of the compensated original co-directional component and the original quadrature component yields the amplitude of the drive response digital signal. Comparing this amplitude with the set target amplitude gives the amplitude difference. A pre-set amplitude control algorithm then calculates the AGC control factor to ensure the stability of the NCO drive signal amplitude; this loop constitutes an amplitude loop. The quartz gyroscope uses the amplitude loop and phase loop to control the NCO to generate a frequency-controllable and amplitude-stable digital excitation signal, which is then output as a corresponding drive voltage signal by the DAC.

[0119] In one embodiment, the controller includes a second analog-to-digital converter; a detection circuit is used to transmit a detection response voltage signal to the second analog-to-digital converter; the second analog-to-digital converter is used to convert the detection response voltage signal into a detection response digital signal; and the controller is used to parse the detection response digital signal to obtain angular velocity information.

[0120] In this embodiment, the detection circuit includes a detection preamplifier and an AC amplification module. The detection preamplifier is used to detect the detection response charge signal generated during interdigital oscillation, convert the detection response charge signal into a detection response voltage signal, and transmit the detection response voltage signal to the AC amplification module; the AC amplification module is used to amplify the detection response voltage signal and transmit the detection response voltage signal to the second ADC.

[0121] In this embodiment, a detection preamplifier (hereinafter referred to as the detection preamplifier) ​​is built using a low-noise precision operational amplifier. The detection preamplifier converts the detection response charge signal into a detection response voltage signal, and an AC amplification module enhances the signal strength of the detection response voltage signal so that the controller can better analyze the amplified detection response voltage signal. Furthermore, when high sampling accuracy is required at the detection end, an 18-bit ADC chip is used as the second ADC, which converts the detection response voltage signal into the corresponding detection response digital signal.

[0122] In one embodiment, the controller includes a digitally controlled oscillator; the original digital reference signal includes an original sine digital signal and an original cosine digital signal; the digitally controlled oscillator is used to generate the original sine digital signal and the original cosine digital signal; the controller is used to demodulate the detection response digital signal based on the original sine digital signal to generate a detection in-phase component, and to demodulate the detection response digital signal based on the original cosine digital signal to generate a detection quadrature component.

[0123] In this embodiment, the dual-channel sinusoidal discrete digital drive signal output by the NCO is used as a reference signal to demodulate the detection response digital signal, thereby obtaining the detection in-direction component and the detection quadrature component.

[0124] In one embodiment, the controller is configured to perform phase compensation on the detected co-directional component and phase compensation on the detected quadrature component; the controller is also configured to perform temperature compensation on the detected co-directional component based on the real-time ambient temperature.

[0125] In this embodiment, a phase difference also exists between the original digital reference signal and the detection response digital signal (i.e., the detection of the same-direction component and the detection of the quadrature component). Therefore, phase compensation can be performed on the detection response digital signal to achieve complete separation of the detection of the quadrature component and the angular velocity (detection of the same-direction component), thereby suppressing the impact of quadrature coupling on the gyroscope's angular velocity measurement accuracy. Furthermore, the angular velocity output of the digital quartz gyroscope can be compensated based on the real-time temperature measured by the temperature sensor, optimizing the full-temperature performance of the digital quartz gyroscope.

[0126] In this embodiment, the controller can demodulate the detected co-directional and quadrature components, and also obtain information such as drive frequency and AGC. The controller can also transmit information such as angular velocity and AGC to a host computer via wireless or wired communication. For example, the controller includes a Universal Synchronous / Asynchronous Receiver / Transmitter (USART) communication interface to provide data for subsequent digital gyroscope optimization, movement adjustment, and other processing.

[0127] In one specific embodiment, based on the implementation methods provided in the above embodiments, a system is established as follows: Figure 3 The schematic diagram of the closed-loop drive circuit shown illustrates this. The target phase is set to 0. A voltage amplifier module can be connected in series after the DAC to increase the oscillation amplitude and improve the sensitivity of the quartz gyroscope. Figure 3 It is understood that the charge output signal of the driving interdigital finger is converted into a corresponding digital signal by the driving preamplifier and the first analog-to-digital converter. Then, the displacement signal of the driving end (i.e., the digital signal of the driving response) is demodulated and filtered in the controller, and then the driving voltage signal is generated by the digital-to-analog converter. The driving closed-loop circuit uses a driving closed-loop scheme with digital phase-locked loop and digital automatic gain control to ensure that the driving interdigital finger always oscillates at its resonant frequency and that the oscillation amplitude of the driving interdigital finger is within the preset amplitude range, so that the oscillation amplitude of the driving interdigital finger remains unchanged or only changes very little.

[0128] In this embodiment, based on the implementation methods provided in the above embodiments, a system is established as follows: Figure 4The schematic diagram of the detection loop shown illustrates this. An AC amplification module can be added after the preamplifier for easier subsequent signal processing. When performing temperature compensation for the detected co-directional component, a temperature sensor can be used to collect the real-time ambient temperature. A third ADC converts the analog temperature signal into a digital temperature signal, which is then transmitted to the controller for processing. The detection loop collects the digital response signal from the interdigital sensor, and the controller performs filtering, demodulation, and other digital signal processing on it, ultimately enabling accurate measurement of the external angular velocity.

[0129] In one embodiment, based on the implementation method provided in any of the above embodiments, a digital quartz gyroscope is constructed, and the digital quartz gyroscope is tested. The results are as follows:

[0130] A frequency sweep test was conducted at ±25Hz of the driving tuning fork resonant frequency. Based on the room-temperature frequency sweep data of the digital quartz gyroscope, the optimal compensation phase angle and C0 compensation coefficient of the driving end could be calculated. These parameters were then programmed into the controller via a host computer. After compensating the driving end of the digital quartz gyroscope, a 600-second static test at room temperature was performed. The original discrete digital reference signal was used to perform in-phase demodulation and quadrature demodulation on the driving response digital signal converted by the ADC. Figure 5 This provides 600 seconds of measured digital data for the original co-directional and original quadrature components of the digital quartz gyroscope's drive terminal. Figure 5 It can be seen that the original in-direction component and the original quadrature component at the driving end have the same magnitude, both being 10^6.

[0131] Phase compensation is performed on the original in-phase component of the driver, and phase compensation and C0 coefficient compensation are performed on the original quadrature component of the driver. This yields the compensated in-phase and quadrature component data, as detailed below. Figure 6 As shown. By Figure 6 It can be seen that the magnitude of the compensated co-directional component is 10^7, which is slightly larger than the original co-directional component of the original driver. The compensated quadrature component of the driver fluctuates around 0, which is much smaller than the original quadrature component of the driver, indicating that the compensation method of the driver is effective.

[0132] After performing drive-end compensation, detection-end phase compensation, and zero-position calibration compensation tests on the digital gyroscope, the compensation parameters were programmed into the controller, and a room-temperature static repeatability test was conducted: the temperature of the chamber was set to 25℃, and after the temperature of the chamber stabilized, the digital quartz gyroscope was powered on and 1800 seconds of static data were collected. Then the power was turned off, and the test was repeated 5 times. Figure 7The measured zero-position data from the room-temperature static test of the digital quartz gyroscope shows that the zero-position of the compensated digital quartz gyroscope can reach the order of 10^-3 (° / S). The zero-position stability is calculated to be 1.26° / h, the zero-position repeatability is 1.76° / h, and the angular random walk is 2.35° / h / sqrt(Hz). This indicates that the digital quartz gyroscope has low white noise in its angular velocity output and good stability and repeatability in its zero position.

[0133] In one specific embodiment, the quartz tuning fork and quartz gyroscope circuitry are integrated into a single digital quartz gyroscope, as shown in the physical diagram below. Figure 8 As shown, its overall structure is relatively small, it uses a 5V±0.2V power supply, and it uses wired output to realize the functions of sending data and powering the external system. The different wire colors represent different signal definitions.

[0134] Temperature cycling tests were conducted on the compensated digital quartz gyroscope to verify its full-temperature performance.

[0135] The test conditions are as follows:

[0136] Power supply: +5VDC;

[0137] Number of warming cycles: 2;

[0138] Operating temperature: -45℃ to 80℃;

[0139] Data acquisition segment: Data from the temperature rise segment from low temperature to high temperature.

[0140] Because digital quartz gyroscopes are calibrated and compensated using data from the heating phase, only the heating phase data is analyzed in the temperature cycling test. Figure 9 The graphs showing the zero-point data of the digital quartz gyroscope during two temperature rise cycles demonstrate that the gyroscope exhibits good zero-point repeatability and excellent stability across the entire temperature range, maintaining a reading on the order of 10^-3 (° / s). Temperature cycling tests further confirm the superior full-temperature performance of the digital quartz gyroscope.

[0141] The quartz gyroscope circuit provided by this invention includes a closed-loop drive circuit. The closed-loop drive circuit includes a drive fork, a drive-end circuit, and a controller. The drive fork refers to the drive end of a quartz tuning fork. The drive-end circuit converts the drive response charge signal generated by the drive fork into a drive response voltage signal and transmits the drive response voltage signal to the controller. The controller generates an original digital reference signal, adjusts the frequency and amplitude of the original digital reference signal based on the drive response voltage signal to generate a drive voltage signal, and transmits the drive voltage signal to the drive-end circuit. The drive-end circuit amplifies the drive voltage signal and applies the amplified drive voltage signal to the drive fork so that the oscillation frequency of the drive fork is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive fork is within a preset amplitude range. In the above process, the frequency and amplitude of the original digital reference signal are adjusted by the drive response voltage signal fed back during the oscillation of the drive fork to generate the drive voltage signal. An amplified driving voltage signal is used to excite the driving fork finger, so that the oscillation frequency of the driving fork finger is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the driving fork finger is within the preset amplitude range, thereby ensuring the stability of the oscillation frequency and the stability of the oscillation amplitude of the driving fork finger.

[0142] Furthermore, the quartz gyroscope circuit also includes a detection circuit, which includes a detection fork, a detection end circuit, and a controller. The detection fork refers to the detection end of the quartz tuning fork. The detection end circuit is used to convert the detection response charge signal generated by the detection fork into a detection response voltage signal and transmit the detection response voltage signal to the controller. The controller is used to analyze the detection response voltage signal to obtain angular velocity information.

[0143] Furthermore, the controller performs digital demodulation and filtering on the drive displacement signal (i.e., the drive response digital signal) and the detection displacement signal (i.e., the detection response digital signal). It employs a digital phase-locked loop (PLL) and digital automatic gain control (AGC) to achieve closed-loop control of the interdigital drive, saving numerous components, simplifying the circuit design, reducing the overall size of the gyroscope, and achieving high precision and small size for the quartz gyroscope. The digital quartz gyroscope increases the compensability of the gyroscope sensor, allowing compensation for the drive interdigital drive within the gyroscope itself, ensuring the driving fork oscillates at its resonant frequency across the entire temperature range. It also provides phase compensation and zero-bias compensation for the detection end. The digital implementation of drive, demodulation, and filtering facilitates control, simplifies gyroscope compensation, and provides good stability and linearity. The controller can perform both in-phase and quadrature demodulation and output data such as drive frequency, AGC, phase, and quadrature components to obtain information about the quartz tuning fork itself, providing a basis for subsequent optimization and improvement of the digital quartz gyroscope.

[0144] Figure 10An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 10 As shown, the electronic device may include a processor 1001, a communications interface 1002, a memory 1003, and a communication bus 1004, wherein the processor 1001, the communications interface 1002, and the memory 1003 communicate with each other via the communication bus 1004. The processor 1001 can call logical instructions in the memory 1003 to execute the processing procedures implemented by the controller in any of the above embodiments.

[0145] Furthermore, the logical instructions in the aforementioned memory 1003 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention embodiment, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0146] On the other hand, the present invention also provides a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to execute the processing implemented by the controller in any of the above embodiments.

[0147] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the processing procedures implemented by the controller in any of the above embodiments.

[0148] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0149] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0150] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A quartz gyroscope circuit, characterized in that, It includes a closed-loop drive circuit; the closed-loop drive circuit includes a drive fork finger, a drive end circuit and a controller, wherein the drive fork finger refers to the drive end of a quartz tuning fork; The driving terminal circuit converts the driving response charge signal generated by the driving interdigit into a driving response voltage signal, and transmits the driving response voltage signal to the controller; The controller generates a raw digital reference signal, adjusts the frequency and amplitude of the raw digital reference signal based on the drive response voltage signal, generates a drive voltage signal, and transmits the drive voltage signal to the drive circuit. The driving circuit amplifies the driving voltage signal and applies the amplified driving voltage signal to the driving fork, so that the oscillation frequency of the driving fork is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the driving fork is within a preset amplitude range. The controller includes a first analog-to-digital converter, which converts the drive response voltage signal into a drive response digital signal; the controller adjusts the frequency and amplitude of the original digital reference signal based on the drive response digital signal to generate a digital excitation signal. The original digital reference signal includes an original sine digital signal and an original cosine digital signal; the controller demodulates the drive response digital signal based on the original sine digital signal to generate an original in-phase component, and demodulates the drive response digital signal based on the original cosine digital signal to generate an original quadrature component; The controller calculates the response amplitude of the drive response digital signal based on the original in-phase component and the original quadrature component, and determines the excitation amplitude of the digital excitation signal based on the response amplitude and the preset target amplitude. The controller calculates the response phase of the drive response digital signal based on the original in-phase component and the original quadrature component, and determines the excitation phase of the digital excitation signal based on the response phase and the preset target phase. The controller performs phase compensation on the original in-phase component based on the resonant frequency, and performs phase compensation on the original quadrature component based on the resonant frequency.

2. The quartz gyroscope circuit according to claim 1, characterized in that, It also includes a detection circuit; the detection circuit includes a detection fork, a detection end circuit and the controller, wherein the detection fork refers to the detection end of the quartz tuning fork; The detection terminal circuit converts the detection response charge signal generated by the detection interdigital fingers into a detection response voltage signal, and transmits the detection response voltage signal to the controller; The controller analyzes the detection response voltage signal to obtain angular velocity information.

3. The quartz gyroscope circuit according to claim 1, characterized in that, The controller also includes a digital-to-analog converter; The driving circuit transmits the driving response voltage signal to the first analog-to-digital converter. The controller transmits the digital excitation signal to the digital-to-analog converter; The digital-to-analog converter converts the digital excitation signal into the driving voltage signal.

4. The quartz gyroscope circuit according to claim 3, characterized in that, The controller includes a digitally controlled oscillator; The digitally controlled oscillator generates the original sine digital signal and the original cosine digital signal.

5. The quartz gyroscope circuit according to claim 4, characterized in that, The controller also includes an automatic gain control module; The digitally controlled oscillator generates the original sine digital signal and the original cosine digital signal based on the excitation frequency, wherein the phase of the original sine digital signal is the target phase; The automatic gain control module generates the digital excitation signal based on the original sinusoidal digital signal and the excitation amplitude, wherein the amplitude of the digital excitation signal is the target amplitude.

6. The quartz gyroscope circuit according to claim 1, characterized in that, The controller performs capacitive compensation on the original quadrature components after phase compensation based on the quadrature component compensation value, wherein the quadrature component compensation value is obtained based on the capacitive performance of the quartz tuning fork.

7. The quartz gyroscope circuit according to claim 2, characterized in that, The controller includes a second analog-to-digital converter; The detection terminal circuit transmits the detection response voltage signal to the second analog-to-digital converter; The second analog-to-digital converter converts the detection response voltage signal into a detection response digital signal; The controller analyzes the detection response digital signal to obtain the angular velocity information.

8. The quartz gyroscope circuit according to claim 7, characterized in that, The controller includes a digitally controlled oscillator; the original digital reference signal includes an original sine digital signal and an original cosine digital signal; The digitally controlled oscillator generates the original sine digital signal and the original cosine digital signal; The controller demodulates the detection response digital signal based on the original sinusoidal digital signal to generate a detection in-direction component, and demodulates the detection response digital signal based on the original cosine digital signal to generate a detection quadrature component.

9. The quartz gyroscope circuit according to claim 8, characterized in that, The controller performs phase compensation on the detected in-phase components and phase compensation on the detected quadrature components. The controller performs temperature compensation on the detected same-direction component based on the real-time ambient temperature.

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