Lissajous frequency modulation MEMS gyroscope control system and parameter excitation method based on phase-locked loop

Abstract

The present invention discloses a Lissajous frequency-modulated MEMS gyroscope control system and parameter excitation method based on a phase-locked loop (PLL), belonging to the field of micromechanical gyroscopes. Based on the phase-frequency characteristics of the MEMS gyroscope's modal vibration displacement, the present invention utilizes a PLL to simultaneously maintain modal resonance and read out the resonant frequency. This eliminates the need for a dedicated frequency readout circuit, thereby simplifying circuit design. The read resonant frequency can be used to obtain an external input angular velocity through subsequent signal processing. By applying a disturbance signal to the modal stiffness, parametric excitation of the modal is achieved, changing the phase-frequency characteristics of the modal vibration displacement, effectively improving the modal quality factor, reducing the frequency noise of the PLL output, and improving the detection accuracy of the final angular velocity output.

Description

Technical Field

[0001] The present invention relates to the field of micromechanical gyroscopes, and more particularly to a control system based on a phase-locked loop (PLL) of a Lissajous frequency modulated MEMS gyroscope and a parameter excitation method thereof. Background Art

[0002] The operating principle of a Lissajous frequency-modulated MEMS gyroscope is to simultaneously drive two spatially orthogonal vibration modes (X mode and Y mode), with a certain difference in the initial resonant frequencies of the two modes. When both modes are driven into resonance, the resonant frequencies of both modes contain information about the external angular velocity input. By reading the modal resonant frequencies and performing signal processing, the external angular velocity can be obtained.

[0003] Parametric excitation technology changes the amplitude-frequency response and phase-frequency response of the mode by applying a stiffness disturbance signal to the MEMS gyroscope mode, which is equivalent to changing the quality factor of the mode. Summary of the Invention

[0004] This paper proposes a Lissajous frequency-modulated MEMS gyroscope control method based on a phase-locked loop (PLL). Based on the phase-frequency characteristics of the MEMS gyroscope's modal vibration displacement, the PLL simultaneously maintains modal resonance and reads the resonant frequency. This eliminates the need for a dedicated frequency readout circuit, simplifying circuit design. The read resonant frequency is then processed to obtain the external input angular velocity. By applying a perturbation signal to the modal stiffness, parametric excitation of the modal is achieved, altering the phase-frequency characteristics of the modal vibration displacement, effectively improving the modal quality factor, reducing the frequency noise of the PLL output, and enhancing the detection accuracy of the final angular velocity output.

[0005] The technical solution adopted in the present invention is:

[0006] The present invention first provides a Lissajous frequency modulation MEMS gyroscope control system based on a phase-locked loop, which includes a MEMS gyroscope, an X-mode amplitude-phase extraction module, an X-mode automatic gain control module, an X-mode phase-locked loop module, an X-mode driving force generation module, a Y-mode amplitude-phase extraction module, a Y-mode automatic gain control module, a Y-mode phase-locked loop module, a Y-mode driving force generation module, and an angular velocity extraction module;

[0007] The X-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating an X-mode vibration displacement signal; the X-mode amplitude-phase extraction module extracts the X-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the X-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the X-mode automatic gain control module obtains the amplitude output of the X-mode automatic gain control module based on the vibration displacement amplitude information; and the X-mode driving force generation module generates an electrostatic force based on the frequency output of the X-mode phase-locked loop and the amplitude output of the X-mode automatic gain control module.

[0008] The Y-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating a Y-mode vibration displacement signal; the Y-mode amplitude-phase extraction module extracts the Y-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the Y-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the Y-mode automatic gain control module obtains the amplitude output of the Y-mode automatic gain control module based on the vibration displacement amplitude information; the Y-mode driving force generation module generates an electrostatic force based on the frequency output of the Y-mode phase-locked loop and the amplitude output of the Y-mode automatic gain control module;

[0009] The angular velocity extraction module obtains the external input angular velocity according to the frequency output of the X-mode phase-locked loop and the frequency output of the Y-mode phase-locked loop in the resonant state.

[0010] Preferably, the phase-locked loop-based Lissajous frequency modulation MEMS gyro control system further includes an X-modal parameter excitation signal generating module and a Y-modal parameter excitation signal generating module;

[0011] The X-mode parametric excitation signal generating module applies a stiffness disturbance signal to the MEMS gyroscope X-mode according to the frequency output of the X-mode phase-locked loop, so that the X-mode is in a resonant state under parametric excitation;

[0012] The Y-mode parameter excitation signal generating module applies a stiffness disturbance signal to the MEMS gyroscope Y-mode according to the frequency output of the Y-mode phase-locked loop, so that the Y-mode is in a resonant state under parameter excitation.

[0013] The present invention also provides a Lissajous frequency modulation MEMS gyroscope control method based on a phase-locked loop, which includes the following steps:

[0014] 1) The X-mode of the MEMS gyroscope is actively driven by electrostatic force, generating an X-mode vibration displacement signal;

[0015] 2) The vibration displacement signal of the MEMS gyroscope's X-mode is converted into a voltage signal. The amplitude-phase extraction module then extracts the vibration displacement phase information and amplitude information. The frequency output of the X-mode phase-locked loop is derived based on the vibration displacement phase information. The amplitude output of the X-mode automatic gain control module is derived based on the vibration displacement amplitude information.

[0016] 3) Based on the frequency output of the X-mode phase-locked loop and the amplitude output of the X-mode automatic gain control module, an electrostatic force of a corresponding frequency is generated to act on step 1); when the X-mode phase-locked loop is closed, the final frequency output of the X-mode phase-locked loop is equal to the resonant frequency of the X-mode, and at this time the X-mode is in a resonant state;

[0017] 4) The Y mode of the MEMS gyroscope is actively driven by electrostatic force, generating a Y mode vibration displacement signal;

[0018] 5) The vibration displacement signal of the MEMS gyroscope's Y mode is converted into a voltage signal. The vibration displacement phase information and vibration displacement amplitude information are then extracted through the amplitude-phase extraction module. The frequency output of the Y mode phase-locked loop is obtained based on the vibration phase information; the amplitude output of the Y mode automatic gain control module is obtained based on the vibration displacement amplitude information.

[0019] 6) Based on the frequency output of the Y-mode phase-locked loop and the amplitude output of the Y-mode automatic gain control module, an electrostatic force of a corresponding frequency is generated to act on step 4); when the Y-mode phase-locked loop is closed, the final frequency output of the Y-mode phase-locked loop is equal to the resonant frequency of the Y-mode, and the Y-mode is in a resonant state;

[0020] 7) When both the X-mode and the Y-mode are in a resonant state, their resonant frequencies contain information about the external input angular velocity. The frequency outputs of the X-mode phase-locked loop and the Y-mode phase-locked loop are used as inputs to the angular velocity extraction module to obtain the external input angular velocity.

[0021] According to an embodiment of the present invention, the step 2) is specifically as follows: the vibration displacement signal x of the X mode of the MEMS gyroscope,

[0022]

[0023] Where t represents time, x a is the amplitude of the X-mode vibration displacement, is the phase of the X-mode vibration displacement;

[0024] The vibration displacement signal is extracted through the amplitude-phase extraction module to obtain the vibration displacement amplitude information x a and vibration displacement phase information Vibration displacement phase After the X-mode phase-locked loop module, the frequency output ω of the X-mode phase-locked loop is obtained.xF ; Vibration displacement amplitude x a After the X-mode automatic gain control module, the amplitude output F of the X-mode automatic gain control module is obtained. xa ;

[0025] The process of processing the vibration displacement signal of the Y mode in step 5) is the same as the process of processing the vibration displacement signal of the X mode in step 2).

[0026] According to an embodiment of the present invention, the vibration displacement phase After the X-mode phase-locked loop module, the frequency output ω of the X-mode phase-locked loop is obtained. xF ; Specifically:

[0027] Vibration displacement phase After entering the X-mode phase-locked loop module, the phase reference value of the modal vibration displacement The difference is subtracted between them, and the difference is passed through the PI controller to generate the phase-locked loop frequency output correction value, which is added to the initial value of the phase-locked loop frequency output as the phase-locked loop final frequency output ω xF ; Due to the effect of PI controller, as long as the vibration displacement phase Phase reference value of modal vibration displacement There is a difference between the frequency output of the phase-locked loop and xF It will continue to change until the vibration displacement phase Phase reference value of modal vibration displacement Equal; according to the principle of gyrodynamics, the vibration displacement phase Phase reference value of modal vibration displacement Equality only occurs in the case of modal resonance, that is, at this time the X mode is in the resonant state, and the final frequency output of the X mode phase-locked loop is ω xF Equal to the resonant frequency ω of the X mode x .

[0028] According to an embodiment of the present invention, the vibration displacement amplitude x a After the X-mode automatic gain control module, the amplitude output F of the X-mode automatic gain control module is obtained. xa ; Specifically:

[0029] Vibration displacement amplitude x a After entering the X-mode automatic gain control module, the modal vibration displacement amplitude reference value x a_ref The difference is subtracted between them, and the difference is passed through the PI controller to generate the driving force amplitude output correction value, which is added to the initial value of the driving force amplitude as the final driving force amplitude output F of the automatic gain control module. xa Due to the effect of PI controller, as long as the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value xa_ref There is a difference between the driving force amplitude output F of the automatic gain control xa It will continue to change until the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value x a_ref equal.

[0030] The present invention also provides a parametric excitation method based on the above method, comprising performing parametric excitation on one of the X mode or the Y mode, or performing parametric excitation on both the X mode and the Y mode simultaneously;

[0031] The parametric excitation of the X mode is as follows: according to the frequency output of the X mode phase-locked loop, a stiffness disturbance signal is applied to the X mode, so that the X mode is in a resonant state under parametric excitation;

[0032] The parametric excitation of the Y mode is as follows: according to the frequency output of the Y mode phase-locked loop, a stiffness disturbance signal is applied to the Y mode to make the Y mode in a resonant state under parametric excitation.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The Lissajous frequency modulation MEMS gyroscope control scheme based on a phase-locked loop proposed in the present invention realizes the functions of maintaining modal resonance and resonant frequency readout simultaneously by utilizing the phase-locked loop, eliminating the need to design a dedicated frequency readout circuit, thereby simplifying the circuit design.

[0035] By applying a disturbance signal to the modal stiffness, the parametric excitation of the mode is achieved, the phase-frequency characteristics of the modal vibration displacement are changed, the modal quality factor is equivalently improved, the frequency noise of the phase-locked loop output is reduced, and the detection accuracy of the final angular velocity output is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the control block diagram of the Lissajous frequency modulation MEMS gyroscope control scheme based on a phase-locked loop and its parameter excitation method provided by the present invention.

[0037] Figure 2 Schematic diagram of the X-mode and Y-mode phase-locked loop modules used in the present invention.

[0038] Figure 3 Schematic diagram of the automatic gain control module for X mode and Y mode used in the present invention.

[0039] Figure 4 This is a schematic diagram of the angular velocity extraction module used in the present invention.

[0040] Figure 5 Schematic diagram of the X-mode and Y-mode parameter excitation signal generation module used in the present invention.

[0041] Figure 6 Schematic diagram of the changes in the phase-frequency characteristics of the X mode and Y mode after the parametric excitation signal is applied. DETAILED DESCRIPTION

[0042] The present invention will now be described in further detail with reference to the accompanying drawings and formulas. It should be understood that the principles herein are intended to explain the present invention, but are not intended to limit the present invention.

[0043] like Figure 1 Figure 1 shows a schematic diagram of a Lissajous frequency-modulated MEMS gyroscope control system based on a phase-locked loop (PLL) according to the present invention. The system includes a MEMS gyroscope, an X-mode amplitude-phase extraction module, an X-mode automatic gain control module, an X-mode PLL module, an X-mode driving force generation module, a Y-mode amplitude-phase extraction module, a Y-mode automatic gain control module, a Y-mode PLL module, a Y-mode driving force generation module, and an angular velocity extraction module. Each module can be implemented in either analog or digital circuits.

[0044] The X-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating an X-mode vibration displacement signal; the X-mode amplitude-phase extraction module extracts the X-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the X-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the X-mode automatic gain control module obtains the amplitude output of the X-mode automatic gain control module based on the vibration displacement amplitude information; and the X-mode driving force generation module generates an electrostatic force based on the frequency output of the X-mode phase-locked loop and the amplitude output of the X-mode automatic gain control module.

[0045] The Y-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating a Y-mode vibration displacement signal; the Y-mode amplitude-phase extraction module extracts the Y-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the Y-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the Y-mode automatic gain control module obtains the amplitude output of the Y-mode automatic gain control module based on the vibration displacement amplitude information; the Y-mode driving force generation module generates an electrostatic force based on the frequency output of the Y-mode phase-locked loop and the amplitude output of the Y-mode automatic gain control module;

[0046] The angular velocity extraction module obtains the external input angular velocity according to the frequency output of the X-mode phase-locked loop and the frequency output of the Y-mode phase-locked loop in the resonant state.

[0047] In a preferred embodiment of the present invention, the phase-locked loop-based Lissajous frequency-modulated MEMS gyroscope control system further includes an X-mode parameter excitation signal generation module and a Y-mode parameter excitation signal generation module; the X-mode parameter excitation signal generation module applies a stiffness disturbance signal to the MEMS gyroscope X mode based on the frequency output of the X-mode phase-locked loop, so that the X mode is in a resonant state under parameter excitation;

[0048] The Y-mode parametric excitation signal generating module applies a stiffness disturbance signal to the Y-mode of the MEMS gyroscope according to the frequency output of the Y-mode phase-locked loop, so that the Y-mode is in a resonant state under parametric excitation. The MEMS gyroscope should have the following functions: (1) When a voltage is applied to a certain electrode, a corresponding electrostatic force is generated on the gyroscope mass block along the X-mode direction. (2) When the gyroscope mass block has a certain displacement along the X-mode direction, the capacitance value between two electrodes of the gyroscope changes. (3) When a voltage is applied to a certain electrode, the stiffness of the X-mode of the gyroscope changes accordingly. (4) When a voltage is applied to a certain electrode, a corresponding electrostatic force is generated on the gyroscope mass block along the Y-mode direction. (5) When the gyroscope mass block has a certain displacement along the Y-mode direction, the capacitance value between two electrodes of the gyroscope changes. (6) When a voltage is applied to a certain electrode, the stiffness of the Y-mode of the gyroscope changes accordingly.

[0049] The Lissajous frequency modulated MEMS gyroscope needs to make both the X mode and the Y mode in a resonant state, and needs to read out the resonant frequencies of the X mode and the Y mode and extract the angular velocity information therefrom.

[0050] The Lissajous frequency modulated MEMS gyroscope based on a phase-locked loop is realized by the following steps.

[0051] The X mode of the MEMS gyroscope is driven by the electrostatic force F x Active drive generates vibration displacement x. Electrostatic force F x is a sine wave signal with a certain frequency, in the following form, where F xa Is the driving force amplitude output by the X-mode automatic gain control module. xF is the driving force frequency output by the X-mode phase-locked loop module.

[0052] F x =F xa cosω xF t

[0053] t represents time; in the electrostatic force F x Under the action of , the X-mode vibration displacement x is as follows:

[0054]

[0055] Where t represents time, xa is the amplitude of the X-mode vibration displacement, is the phase of the X-mode vibration displacement.

[0056] The vibration displacement signal x of the X mode of the MEMS gyroscope is extracted through the amplitude-phase extraction module to obtain the vibration displacement amplitude information x a and vibration displacement phase information Vibration displacement phase After the X-mode phase-locked loop module, the frequency output ω of the X-mode phase-locked loop is obtained. xF . Vibration displacement amplitude x a After the X-mode automatic gain control module, the amplitude output F of the X-mode automatic gain control module is obtained. xa The frequency output of X-mode phase-locked loop is ω xF , and the amplitude output F of the X-mode automatic gain control module xa , through the X-modal force generation module, generates an electrostatic force F x .

[0057] like Figure 2 The figure shows the schematic diagram of the X-mode and Y-mode phase-locked loop modules used in the present invention, wherein the modal vibration displacement phase reference value, the frequency output initial value, and the PI controller parameter k p , PI controller parameter k i It is configurable, and the parameter settings of the phase-locked loop module of X mode and Y mode can be different. Taking X mode as an example, the modal vibration displacement phase reference value is set to the X mode resonance phase, and the vibration displacement phase After entering the phase-locked loop module, the phase reference value of the modal vibration displacement The difference is subtracted between them, and the difference is passed through the PI controller to generate the phase-locked loop frequency output correction value, which is added to the initial value of the phase-locked loop frequency output as the phase-locked loop final frequency output ω xF Due to the effect of PI controller, as long as the vibration displacement phase Phase reference value of modal vibration displacement There is a difference between the frequency output of the phase-locked loop and xF It will continue to change until the vibration displacement phase Phase reference value of modal vibration displacement Equal. According to the principle of gyrodynamics, the vibration displacement phase Phase reference value of modal vibration displacement Equality only occurs in the case of modal resonance, that is, at this time the X mode is in the resonant state, and the final frequency output of the X mode phase-locked loop is ω xF Equal to the resonant frequency ω of the X mode x In order to meet the final frequency output ω of the X-mode phase-locked loop xFLock the resonant frequency ω of the X mode x , requiring a configurable PI controller parameter k p 、k i Above a certain threshold. PI controller parameter k p 、k i It also affects the noise in the PLL frequency output, k p 、k i The smaller it is, the smaller the frequency output noise is.

[0058] like Figure 3 As shown in the figure, the automatic gain control module schematic diagram of the X mode and Y mode used in the present invention, wherein the modal vibration displacement amplitude reference value, the driving force amplitude initial value, the PI controller parameter k p , PI controller parameter k i It is configurable, and the automatic gain control parameter settings of X mode and Y mode can be different. Taking X mode as an example, the modal vibration displacement amplitude reference value is set to a certain desired vibration displacement amplitude, and the vibration displacement amplitude x a After entering the automatic gain control module, the modal vibration displacement amplitude reference value x a_ref The difference is subtracted between them, and the difference is passed through the PI controller to generate the driving force amplitude output correction value, which is added to the initial value of the driving force amplitude as the final driving force amplitude output F of the automatic gain control module. xa Due to the effect of PI controller, as long as the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value x a_ref There is a difference between the driving force amplitude output F of the automatic gain control xa It will continue to change until the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value x a_ref equal.

[0059] In the same way, the Y mode can also be excited in the resonant state.

[0060] At this time, the dynamic equations of the X mode and the Y mode are as follows.

[0061]

[0062]

[0063] m x represents the mass of the X mode, c x,eff represents the equivalent damping of X mode, k x,eff represents the equivalent stiffness of the X mode, m y represents the mass of the Y mode, c y,eff represents the equivalent damping of the Y mode, k y,effrepresents the equivalent stiffness of the Y mode, and t represents time;

[0064] When both the X-mode and the Y-mode are in resonance due to the phase-locked loop, their resonance frequencies contain the external input angular velocity information, and the angular velocity information is modulated to the difference frequency (ω) between the X-mode and Y-mode resonance frequencies. x -ω y ) and the modal resonant frequency is directly read out from the frequency output of the phase-locked loop.

[0065] ω x =ω ox +KΩ z sin((ω x -ω y )t)=ω xF

[0066] ω y =ω oy +KΩ z sin((ω x -ω y )t)=ω yF

[0067] K represents the angular velocity conversion gain, Ω z Represents the external input angular velocity to be detected, ω ox represents the initial resonant frequency of mode X, ω oy represents the initial resonant frequency of the Y mode, and t represents the time;

[0068] In order to obtain angular velocity information, after reading the X-mode and Y-mode resonant frequencies, demodulation and filtering are required to extract the angular velocity information.

[0069] The frequency output of the X-mode phase-locked loop and the frequency output of the Y-mode phase-locked loop are used as inputs of the angular velocity extraction module to obtain the external input angular velocity.

[0070] like Figure 4 The figure shows the schematic diagram of the angular velocity extraction module used in the present invention. The frequency output ω of the X-mode phase-locked loop x and the frequency output of the Y-mode phase-locked loop ω y As the module input. The subtractor is used to x and ω y Subtract to get (ω x -ω y ), the integrator pair (ω x -ω y ) is integrated over time, and we get (ω x -ω y )t is used as the reference signal for multiplication demodulation. After multiplication demodulation of a signal of a certain frequency, a DC component and a double frequency component are obtained. Figure 4 The low-pass filter is used to filter out the double frequency component appearing after multiplication demodulation and retain the DC component. The DC component contains the external input angular velocity to be detected and can be used to characterize the angular velocity detected by the gyroscope.

[0071] Based on the frequency output of the X-mode phase-locked loop, a stiffness perturbation signal is applied to the X-mode, placing it in a resonant state under parametric excitation. This stiffness perturbation signal does not change the modal resonant frequency, but only the modal frequency response. Therefore, applying the stiffness perturbation signal does not affect the normal reading of the angular velocity signal. The dynamic equation for the X-mode at this point is as follows.

[0072]

[0073] k tx,ac represents the amplitude of the X-mode stiffness changed by the stiffness disturbance signal, Represents the phase shift of the stiffness disturbance signal.

[0074] Based on the frequency output of the Y-mode phase-locked loop, a stiffness perturbation signal is applied to the Y-mode, placing it in a resonant state under parametric excitation. This stiffness perturbation signal does not change the modal resonant frequency, but only the modal frequency response. Therefore, applying the stiffness perturbation signal does not affect the normal reading of the angular velocity signal. The dynamic equation for the X-mode at this point is as follows.

[0075]

[0076] k ty,ac represents the amplitude of the Y-mode stiffness changed by the stiffness disturbance signal, Represents the phase shift of the stiffness disturbance signal.

[0077] Figure 6 The changes in the phase-frequency characteristics after applying parametric excitation signals to the X and Y modes, as well as the changes in the phase-frequency characteristics assuming a direct increase in the quality factor, are shown. Applying a parametric excitation signal and directly increasing the quality factor have the same effect on the phase-frequency characteristics, so applying a parametric excitation signal is equivalent to increasing the modal quality factor. In this case, the lower threshold of the PI controller parameters of the phase-locked loop module is lowered, allowing the PI controller parameters of the phase-locked loop module to be set to smaller values, reducing the noise in the phase-locked loop frequency output and the noise in the angular velocity output.

Claims

1. A Lissajous frequency modulated MEMS gyroscope control system based on a phase-locked loop, characterized in that: Includes MEMS gyroscope, X-mode amplitude-phase extraction module, X-mode automatic gain control module, X-mode phase-locked loop module, X-mode driving force generation module, Y-mode amplitude-phase extraction module, Y-mode automatic gain control module, Y-mode phase-locked loop module, Y-mode driving force generation module, and angular velocity extraction module; The X-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating an X-mode vibration displacement signal; the X-mode amplitude-phase extraction module extracts the X-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the X-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the X-mode automatic gain control module obtains the amplitude output of the X-mode automatic gain control module based on the vibration displacement amplitude information; and the X-mode driving force generation module generates an electrostatic force based on the frequency output of the X-mode phase-locked loop and the amplitude output of the X-mode automatic gain control module. The Y-mode driving force generation module generates an electrostatic force to drive the X-mode of the MEMS gyroscope, thereby generating a Y-mode vibration displacement signal; the Y-mode amplitude-phase extraction module extracts the Y-mode vibration displacement signal to obtain vibration displacement phase information and vibration displacement amplitude information; the Y-mode phase-locked loop module obtains the frequency output of the X-mode phase-locked loop based on the vibration displacement phase information; the Y-mode automatic gain control module obtains the amplitude output of the Y-mode automatic gain control module based on the vibration displacement amplitude information; the Y-mode driving force generation module generates an electrostatic force based on the frequency output of the Y-mode phase-locked loop and the amplitude output of the Y-mode automatic gain control module; The angular velocity extraction module obtains the external input angular velocity according to the frequency output of the X-mode phase-locked loop and the frequency output of the Y-mode phase-locked loop in the resonant state.

2. The Lissajous frequency modulated MEMS gyroscope control system based on a phase-locked loop according to claim 1, characterized in that: It also includes an X-modal parameter excitation signal generating module and a Y-modal parameter excitation signal generating module; The X-mode parametric excitation signal generating module applies a stiffness disturbance signal to the MEMS gyroscope X-mode according to the frequency output of the X-mode phase-locked loop, so that the X-mode is in a resonant state under parametric excitation; The Y-mode parameter excitation signal generating module applies a stiffness disturbance signal to the MEMS gyroscope Y-mode according to the frequency output of the Y-mode phase-locked loop, so that the Y-mode is in a resonant state under parameter excitation.

3. A Lissajous frequency modulation MEMS gyroscope control method based on a phase-locked loop, characterized in that The following steps are involved: 1) The X-mode of the MEMS gyroscope is actively driven by electrostatic force, generating an X-mode vibration displacement signal; 2) The vibration displacement signal of the MEMS gyroscope's X-mode is converted into a voltage signal. The amplitude-phase extraction module then extracts the vibration displacement phase information and amplitude information. The frequency output of the X-mode phase-locked loop is derived based on the vibration displacement phase information. The amplitude output of the X-mode automatic gain control module is derived based on the vibration displacement amplitude information. 3) Based on the frequency output of the X-mode phase-locked loop and the amplitude output of the X-mode automatic gain control module, an electrostatic force of a corresponding frequency is generated to act on step 1); when the X-mode phase-locked loop is closed, the final frequency output of the X-mode phase-locked loop is equal to the resonant frequency of the X-mode, and at this time the X-mode is in a resonant state; 4) The Y mode of the MEMS gyroscope is actively driven by electrostatic force, generating a Y mode vibration displacement signal; 5) The vibration displacement signal of the MEMS gyroscope's Y mode is converted into a voltage signal. The vibration displacement phase information and vibration displacement amplitude information are then extracted through the amplitude-phase extraction module. The frequency output of the Y mode phase-locked loop is obtained based on the vibration phase information; the amplitude output of the Y mode automatic gain control module is obtained based on the vibration displacement amplitude information. 6) Based on the frequency output of the Y-mode phase-locked loop and the amplitude output of the Y-mode automatic gain control module, an electrostatic force of a corresponding frequency is generated to act on step 4); when the Y-mode phase-locked loop is closed, the final frequency output of the Y-mode phase-locked loop is equal to the resonant frequency of the Y-mode, and the Y-mode is in a resonant state; 7) When both the X-mode and the Y-mode are in a resonant state, their resonant frequencies contain information about the external input angular velocity. The frequency outputs of the X-mode phase-locked loop and the Y-mode phase-locked loop are used as inputs to the angular velocity extraction module to obtain the external input angular velocity.

4. The Lissajous frequency modulation MEMS gyroscope control method based on a phase-locked loop according to claim 3, characterized in that: The step 2) is specifically as follows: the vibration displacement signal x of the X mode of the MEMS gyroscope, Where t represents time, x a is the amplitude of the X-mode vibration displacement, is the phase of the X-mode vibration displacement; The vibration displacement signal is extracted through the amplitude-phase extraction module to obtain the vibration displacement amplitude information x a and vibration displacement phase information Vibration displacement phase After the X-mode phase-locked loop module, the frequency output ω of the X-mode phase-locked loop is obtained. xF ; Vibration displacement amplitude x a After the X-mode automatic gain control module, the amplitude output F of the X-mode automatic gain control module is obtained. xa ; The process of processing the vibration displacement signal of the Y mode in step 5) is the same as the process of processing the vibration displacement signal of the X mode in step 2).

5. The Lissajous frequency modulated MEMS gyroscope control method based on a phase-locked loop according to claim 4, characterized in that: The vibration displacement phase After the X-mode phase-locked loop module, the frequency output ω of the X-mode phase-locked loop is obtained. xF ; Specifically: Vibration displacement phase After entering the X-mode phase-locked loop module, the phase reference value of the modal vibration displacement The difference is subtracted between them, and the difference is passed through the PI controller to generate the phase-locked loop frequency output correction value, which is added to the initial value of the phase-locked loop frequency output as the phase-locked loop final frequency output ω xF ; Due to the effect of PI controller, as long as the vibration displacement phase Phase reference value of modal vibration displacement There is a difference between the frequency output of the phase-locked loop and xF It will continue to change until the vibration displacement phase Phase reference value of modal vibration displacement Equal; according to the principle of gyrodynamics, the vibration displacement phase Phase reference value of modal vibration displacement Equality only occurs in the case of modal resonance, that is, at this time the X mode is in the resonant state, and the final frequency output of the X mode phase-locked loop is ω xF Equal to the resonant frequency ω of the X mode x .

6. The Lissajous frequency modulation MEMS gyroscope control method based on a phase-locked loop according to claim 4, characterized in that: The vibration displacement amplitude x a After the X-mode automatic gain control module, the amplitude output F of the X-mode automatic gain control module is obtained. xa ; Specifically: Vibration displacement amplitude x a After entering the X-mode automatic gain control module, the modal vibration displacement amplitude reference value x a_ref The difference is subtracted between them, and the difference is passed through the PI controller to generate the driving force amplitude output correction value, which is added to the initial value of the driving force amplitude as the final driving force amplitude output F of the automatic gain control module. xa Due to the effect of PI controller, as long as the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value x a_ref There is a difference between the driving force amplitude output F of the automatic gain control xa It will continue to change until the vibration displacement amplitude x a and the modal vibration displacement amplitude reference value x a_ref equal.

7. A parameter excitation method based on the method of claim 3, characterized in that: Including parametric excitation of one of the X mode or the Y mode, or parametric excitation of both the X mode and the Y mode; The parametric excitation of the X mode is as follows: according to the frequency output of the X mode phase-locked loop, a stiffness disturbance signal is applied to the X mode, so that the X mode is in a resonant state under parametric excitation; The parametric excitation of the Y mode is as follows: according to the frequency output of the Y mode phase-locked loop, a stiffness disturbance signal is applied to the Y mode to make the Y mode in a resonant state under parametric excitation.

Images