A feedback type sensing method and device based on a weak coupling resonant type sensor

Abstract

This application provides a method and apparatus based on a weakly coupled resonant sensor. In executing the method, a disturbance signal is first obtained by converting the measured physical quantity. This disturbance signal is then input into a target sensor, causing the target sensor to generate at least one resonant signal based on the disturbance signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor, which generates at least one resonant signal through modal localization. Finally, a feedback signal is generated and output based on the obtained resonant signal. In this way, the generated feedback signal balances the stiffness disturbance signal acting on the target sensor, and the feedback signal is output as the sensing result. This decouples the sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor from the overall measurement range of the sensor. Thus, without affecting the ultra-high sensitivity of the multi-degree-of-freedom weakly coupled resonator, the detection range of the sensor is greatly expanded.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a feedback sensing method and apparatus based on a weakly coupled resonant sensor. Background Technology

[0002] A resonant sensor is a sensor that uses a resonant element to convert the measured parameter into a frequency signal; it is also called a frequency sensor. When the measured parameter changes, the natural vibration frequency of the vibrating element changes accordingly. Through a corresponding measurement circuit, an electrical signal that is related to the measured parameter can be obtained. Resonant sensors are widely used in many fields due to their advantages such as small size, light weight, compact structure, high resolution, high accuracy, and ease of data transmission, processing, and storage, especially in the measurement of force, acceleration, micro-masses, electric fields, and magnetic fields.

[0003] In recent years, to develop high-sensitivity resonant sensors, multi-degree-of-freedom weakly coupled resonant sensors have been developed based on single-degree-of-freedom resonant sensors by applying modal localization effects. By forming weakly coupled connections between multiple symmetrical resonators, when the system receives a measured physical quantity, energy is redistributed among these resonators. By detecting the amplitude ratio and amplitude difference of the multiple resonators, the magnitude of the measured physical quantity can be calculated. Compared to traditional resonant sensors, weakly coupled resonant sensors utilize modal localization effects to achieve a significant improvement in detection sensitivity. However, due to the extremely high sensitivity of existing weakly coupled resonant sensors, the range of measurable physical quantities is greatly limited, hindering their widespread application. Summary of the Invention

[0004] In view of this, this application provides a feedback sensing method and device based on a weakly coupled resonant sensor, which aims to broaden the detection range of the sensor without affecting the ultra-high sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor.

[0005] In a first aspect, this application provides a feedback sensing method based on a weakly coupled resonant sensor, the method comprising:

[0006] Receive a disturbance signal, which is obtained by converting the physical quantity to be measured;

[0007] The disturbance signal is input to the target sensor so that the target sensor generates at least one resonant signal based on the disturbance signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor.

[0008] After detecting at least one resonant signal generated by the target sensor, a feedback signal is generated based on the at least one resonant signal to balance the disturbance signal according to the feedback signal;

[0009] The feedback signal is output as the measurement result.

[0010] Optionally, the target sensor includes a plurality of mutually coupled resonators, and the step of causing the target sensor to generate at least one resonant signal according to the disturbance signal includes:

[0011] The multiple mutually coupled resonators in the target sensor are adjusted to the target vibration mode frequency;

[0012] The perturbation signal is used to induce modal localization in the target sensor, generating at least one resonant signal.

[0013] Optionally, after inputting the disturbance signal into the target sensor to cause the target sensor to generate at least one resonant signal based on the disturbance signal, the method further includes:

[0014] Detect the actual vibration mode frequency of the target sensor;

[0015] A tuning voltage signal is generated based on the actual vibration mode frequency, and the tuning voltage signal is used to adjust the vibration mode frequency required by the target sensor.

[0016] Optionally, generating a feedback signal based on the at least one resonant signal includes:

[0017] Demodulate each of the at least one resonant signal;

[0018] The resonant signal information is determined based on the demodulated resonant signal, and the resonant signal information includes the amplitude, amplitude ratio, or amplitude difference corresponding to the at least one resonant signal;

[0019] A feedback signal is generated based on the resonant signal information.

[0020] Optionally, the target sensor generates a feedback signal based on the resonant signal information, including:

[0021] A negative feedback control signal is generated based on the resonant signal information. The negative feedback control signal is used to control the target sensor's ability to balance disturbance signals.

[0022] A feedback signal is generated based on the negative feedback control signal to balance the disturbance signal.

[0023] Optionally, balancing the disturbance signal according to the feedback signal includes:

[0024] The feedback signal is input to the target sensor;

[0025] The feedback signal is used to cancel the disturbance signal received by the target sensor, so that the amplitude, amplitude ratio, or amplitude difference of the resonant signal generated by the target sensor returns to its initial value.

[0026] Secondly, this application provides a feedback sensing device based on a weakly coupled resonant sensor, the device comprising: a disturbance signal receiving module, a resonant signal generating module, a feedback signal generating module, and a feedback signal output module;

[0027] The disturbance signal receiving module is used to receive disturbance signals, which are obtained by converting the physical quantity to be measured.

[0028] The resonant signal generation module is used to input the disturbance signal into the target sensor so that the target sensor generates at least one resonant signal according to the disturbance signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor.

[0029] The feedback signal generation module is used to generate a feedback signal based on the at least one resonant signal generated by the target sensor after detecting it, so as to balance the disturbance signal based on the feedback signal.

[0030] The feedback signal output module is used to output the feedback signal as a measurement result.

[0031] Optionally, the target sensor is a resonant sensor, wherein the target sensor includes multiple mutually coupled resonators, and the resonant signal generation module is further used to adjust the multiple mutually coupled resonators of the target sensor to the target vibration mode frequency, and then use the disturbance signal to cause the target sensor to undergo a mode localization effect, thereby generating at least one resonant signal.

[0032] Optionally, the feedback signal generation module is further configured to demodulate the at least one resonant signal respectively, and then determine the resonant signal information based on the demodulated resonant signal. The resonant signal information includes the amplitude, amplitude ratio or amplitude difference corresponding to the at least one resonant signal, and finally generate a feedback signal based on the resonant signal information.

[0033] Thirdly, this application provides a sensing system that applies the feedback sensing method based on a weakly coupled resonant sensor as described in any one of the first aspects above.

[0034] This application provides a feedback sensing method based on a weakly coupled resonant sensor. In executing the method, a disturbance signal is first obtained by converting the measured physical quantity. This disturbance signal is then input into a target sensor, causing the target sensor to generate at least one resonant signal based on the disturbance signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor, which obtains at least one resonant signal through modal localization. Finally, a feedback signal is generated based on the obtained resonant signal to balance the disturbance signal acting on the target sensor. In this way, by balancing the stiffness disturbance signal through the generated feedback signal, the feedback signal is output as the sensing result. This decouples the sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor from the overall range of the sensor. Instead, the range of the sensor is determined by the range of the feedback signal, thus expanding the sensor's range. Therefore, without affecting the ultra-high sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor, the detection range of the sensor is greatly broadened. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in this embodiment or the prior art, the drawings used in the description of the embodiment or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 A flowchart illustrating a method of a feedback sensing method based on a weakly coupled resonant sensor provided in an embodiment of this application;

[0037] Figure 2 A simplified model diagram of a target sensor for a feedback sensing method based on a weakly coupled resonant sensor provided in an embodiment of this application;

[0038] Figure 3 A specific circuit diagram illustrating a feedback sensing method based on a weakly coupled resonant sensor provided in an embodiment of this application;

[0039] Figure 4 Another method flowchart for the feedback sensing method based on a weakly coupled resonant sensor provided in the embodiments of this application;

[0040] Figure 5 A schematic diagram of a feedback sensing device based on a weakly coupled resonant sensor provided in an embodiment of this application;

[0041] Figure 6 This is another schematic diagram of a feedback sensing device based on a weakly coupled resonant sensor provided in an embodiment of this application. Detailed Implementation

[0042] As mentioned earlier, a resonant sensor is a type of sensor that uses a resonant element as its sensing element to achieve measurement based on mechanical resonance technology. Its working principle is to directly convert the change in the measured quantity into a change in the object's resonant characteristics, thereby measuring parameters such as pressure, displacement, and density. The inherent resonant characteristics of the resonant element, the resonant oscillator, determine its high sensitivity and resolution. Compared to traditional single-resonant sensors, weakly coupled resonant sensors form a weakly coupled connection between multiple symmetrical resonators, utilizing the modal localization effect to achieve a significant increase in detection sensitivity. However, the higher the sensitivity of a sensor utilizing the modal localization effect, the smaller the change in the measured quantity it can identify, i.e., the smaller the detection range. Moreover, the output of a modal localization sensor theoretically has a weakly nonlinear relationship with the measured quantity; that is, the sensor's sensitivity varies when measuring small disturbance signals within a certain range. If a linear function is used to fit the relationship between the output and input, the obtained measured value will have an error compared to the actual value. Sensors that utilize modal localization can only measure within a range where there is a high linear relationship between the output and the measured quantity, which to some extent limits the sensor's measurement range.

[0043] In view of this, this application provides a feedback sensing method and apparatus based on a weakly coupled resonant sensor. When executing the method, a disturbance signal is first obtained by converting the physical quantity to be measured. This disturbance signal is then input to a target sensor, causing the target sensor to generate at least one resonant signal based on the disturbance signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor, which obtains at least one resonant signal through modal localization. Finally, a feedback signal is generated based on the obtained resonant signal to balance the disturbance signal acting on the target sensor. In this way, the feedback signal cancels out the disturbance signal received by the target sensor, causing the amplitude, amplitude ratio, or amplitude difference of the resonant signal generated by the target sensor to return to its initial value. Since the feedback signal can cancel out the disturbance signal received by the target sensor, the magnitude of the physical quantity to be measured can be obtained from the feedback signal. Therefore, the sensor's measurement range is determined by the magnitude of the feedback signal that cancels out the disturbance signal, and is not limited by the sensitivity of its weakly coupled resonator. Thus, without affecting the ultra-high sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor, the sensor's detection range can be greatly expanded.

[0044] The method provided in this application can be applied to multi-degree-of-freedom weakly coupled resonant sensors, expanding the sensor's detection range and reducing limitations on its application scope. The method provided in this application can be used to measure various physical quantities, such as force, acceleration, tilt angle, electric field, or magnetic field.

[0045] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0046] See Figure 1 , Figure 1 A flowchart of a feedback sensing method based on a weakly coupled resonant sensor provided in this application embodiment, the method comprising:

[0047] S101: Receive disturbance signals.

[0048] The disturbance signal is derived from the measured physical quantity. The measured physical quantity can be a force, acceleration, tilt angle, electric field, or magnetic field, etc. Different physical quantities can be converted into stiffness disturbances and applied to the target sensor.

[0049] S102: Input the disturbance signal into the target sensor so that the target sensor generates at least one resonant signal based on the modal localization effect of the disturbance signal.

[0050] Among them, target sensors can be used to measure different physical quantities. A sensor is a detection device that can sense the information being measured and transform the sensed information into electrical signals or other required forms of information output according to certain rules, so as to meet the requirements of information transmission, processing, storage, display, recording and control.

[0051] In this embodiment, the target sensor is a resonant sensor. Based on resonance technology, it uses the vibration frequency, phase, and amplitude of a resonator as sensitive parameters to measure parameters such as force, acceleration, tilt angle, electric field, or magnetic field. Depending on the resonant element, resonant sensors can be classified into vibrating wire type, vibrating cylinder type, vibrating beam type, diaphragm type, and piezoelectric resonant type, etc., and are mainly used to measure physical quantities such as pressure, torque, density, acceleration, and temperature.

[0052] The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor. This sensor consists of multiple (at least two) symmetrical resonators connected by mechanical and / or electrostatic coupling. Utilizing modal localization, the magnitude of the detected quantity is calculated by detecting the ratio and difference in vibration amplitudes of the multiple resonators.

[0053] The modal localization effect can be specifically defined as follows: "In a mismatched, weakly coupled system, vibrational energy cannot propagate infinitely far; instead, it is locally concentrated in the subsystems near the driving energy source." In an ideal multi-degree-of-freedom weakly coupled resonant system, the amplitudes of the resonators are identical when undisturbed. When the inherent characteristics (mass or stiffness) of one of the resonators are disturbed, the mode shapes of the resonator change drastically. By detecting changes in the vibration modes (amplitude, amplitude ratio, or amplitude difference) of a multi-degree-of-freedom weakly coupled system, changes in the inherent characteristics of the subsystem can be sensed. Utilizing the local energy concentration effect of vibration modes, a significant improvement in detection sensitivity is achieved, and sensors based on this principle exhibit excellent environmental adaptability.

[0054] The resonant signal is generated when the mode shapes of the resonators in the target sensor change due to modal localization after a disturbance signal is applied. Since the target sensor can contain multiple resonators, multiple resonant signals can be generated. The generated resonant signal is a modulated signal; the target sensor modulates the low-frequency disturbance signal into the high-frequency resonant signal through modal localization. During the transmission of the resonant signal, signal amplification is also performed, thus facilitating signal propagation.

[0055] Optionally, before the target sensor experiences modal localization, it can use a specific circuit to track and lock the vibration mode frequency of the desired resonator in a multi-degree-of-freedom weakly coupled resonant sensor, thereby driving the weakly coupled resonator in the target sensor to its operating state. This specific circuit can be a phase-locked loop (PLL) circuit or a self-excited oscillation circuit. Alternatively, an automatic gain control circuit can be added to the specific circuit for more precise control of the vibration mode frequency.

[0056] Optionally, the resonant signal of the target sensor can be obtained by the following method: First, the mutually coupled resonators in the target sensor are adjusted to the target vibration mode frequency, at which point each resonator is driven to a resonant state. Then, the received disturbance signal is applied to the target sensor. Finally, the resonant signal of each resonator in the target sensor is detected. Of course, other methods can also be used to obtain the resonant signal without affecting the normal operation of the embodiments of this application.

[0057] Optionally, before adjusting the multiple mutually coupled resonators of the target sensor to the target vibration mode frequency, the actual vibration mode frequency of the target sensor can be detected. Then, a tuning voltage signal is generated based on the actual vibration mode frequency. Finally, the tuning voltage signal is used to adjust the required vibration mode frequency of the target sensor. Tuning is performed to ensure that each resonator in the sensor meets the conditions required for modal localization. By changing the operating vibration mode of the resonators in the sensor, the frequency of the oscillation circuit in the resonators is adjusted to reach the required range of the target operating mode, so that the resonators can resonate in the operating vibration mode when receiving a disturbance signal. The resulting signal is called the tuning voltage signal. Optionally, adjusting the vibration mode frequency of the resonators can also be used to adjust each resonator to different bias points according to actual needs, thereby changing the measurement bandwidth of the target sensor and affecting the measurement range of the target sensor. Optionally, since each resonator in the target sensor needs to be symmetrical, that is, the effective stiffness ratio or mass ratio of each resonator is equal, but the process error in actual manufacturing may cause mismatch between each resonator, the tuning voltage signal can also be used to adjust the mismatch between each resonator to keep it within a reasonable range.

[0058] S103: After detecting at least one resonant signal generated by the target sensor, a feedback signal is generated based on the at least one resonant signal to balance the disturbance signal based on the feedback signal.

[0059] In this process, feedback involves coupling the signal output to the input. This feedback signal is typically generated based on a negative feedback control signal and is primarily used to counteract the effects of disturbance signals on the target sensor. This adjusts the amplitude, amplitude ratio, or amplitude difference of the resonant signal generated by the target sensor, balancing these values ​​around a predetermined reference bias point to control the measurement range of the target sensor. Optionally, different reference bias points can be set to change the range of the measured physical quantity. The feedback signal can be a voltage signal, a current signal, or other control signals. For example, when the target sensor is an accelerometer, the feedback signal can be a voltage signal, which can be converted into an electrostatic force applied to the target sensor to counteract the disturbance signal received by the sensor. In some possible methods, the feedback signal can be obtained as follows: First, the detected multiple resonant signals are demodulated to obtain multiple demodulated resonant signals. Then, calculations are performed on these demodulated resonant signals to obtain the amplitude ratio, amplitude difference, or other amplitude information between the resonant signals, which serves as the resonant signal information. Finally, a feedback signal is generated based on the obtained resonant signal information. Of course, other methods can also be used to extract the resonant signal information from the resonant signal to generate the feedback information, without affecting the normal operation of the embodiments of this application.

[0060] Optionally, either coherent demodulation or non-coherent demodulation can be used to demodulate the resonant signal. Coherent demodulation, also called synchronous detection, is applicable to the demodulation of all linearly modulated signals. Coherent demodulation involves using a multiplier to multiply a reference signal that is coherent (in phase and frequency) with the carrier frequency. Non-coherent demodulation, on the other hand, is a demodulation method that does not require extracting carrier information.

[0061] Optionally, the feedback signal can be generated based on the resonant signal information as follows: First, a negative feedback control signal is generated based on the resonant signal information. This negative feedback control signal is used to control the target sensor's ability to suppress external interference. Then, a feedback signal is generated based on the negative feedback control signal. The negative feedback control signal is mainly used to control the target sensor to suppress external noise and interference and to control the target sensor's response speed to disturbance signals. Optionally, the feedback signal can be used to satisfy the conditions required by the negative feedback control signal to maintain the stability and robustness of the entire feedback sensing method. Modern control methods, such as optimal control methods, adaptive control methods, or robust control methods, can be used. Of course, other methods can also be used to obtain the feedback signal, without affecting the normal implementation of the embodiments of this application.

[0062] Alternatively, a feedback signal can be input to the target sensor to cancel the disturbance signal received by the target sensor, so that the amplitude, amplitude ratio, or amplitude difference of the resonant signal generated by the target sensor returns to its initial value.

[0063] S104: Output the feedback signal as the measurement result.

[0064] Since the feedback signal at this time can cancel out the disturbance signal received by the target sensor, the magnitude of the physical quantity to be measured can be directly obtained from the feedback signal.

[0065] This application embodiment uses a disturbance signal converted from the measured physical quantity to act on the target sensor to obtain a resonant signal. Information from this resonant signal is used to generate a feedback signal to balance the disturbance signal, and this feedback signal is output as the test result. This achieves decoupling between the sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor and the overall measurement range of the sensor. The feedback capability of the sensor determines its measurement range, solving the problem of the previously existing target sensor having a small detection range due to the extremely high sensitivity of its multi-degree-of-freedom weakly coupled resonator. Furthermore, the multi-degree-of-freedom weakly coupled resonant sensor in this application utilizes the modal localization effect to convert, modulate, and amplify the measured physical quantity. As the disturbance signal changes, the feedback signal can maintain the amplitude, amplitude ratio, or amplitude difference of the target sensor's resonant signal within the working range. Therefore, the weak nonlinear relationship between the output of the modal localization sensor and the measured quantity can be ignored, which also broadens the sensor's measurement range to some extent. Thus, without affecting the ultra-high sensitivity of its multi-degree-of-freedom weakly coupled resonator, the sensor's detection range is greatly expanded.

[0066] The above describes the feedback sensing method based on a weakly coupled resonant sensor provided in the embodiments of this application. The following describes the sensing method by building a specific circuit system in conjunction with a specific application scenario.

[0067] In this embodiment, the target sensor is a single-axis accelerometer, such as... Figure 2 As shown, this figure is a simplified model diagram of a target sensor based on a feedback sensing method using a weakly coupled resonant sensor, provided in an embodiment of this application.

[0068] The single-axis accelerometer includes: an anchor point 1, an elastic support beam 2, a sensitive mass block 3, an upper electrode 4, a lower electrode 5, a micro-lever amplification structure 6, a stress output terminal 7, two single-degree-of-freedom resonators R1 and R2, and a mechanical coupling structure 8. Resonator R1 comprises a main resonant structure R11, a tuning electrode module R12, a driving electrode module R13, and a detection electrode module R14. Resonator R2 comprises a main resonant structure R21, a tuning electrode module R22, a driving electrode module R23, and a detection electrode module R24.

[0069] The specific connection method of the above components is as follows: Anchor point 1 is connected to elastic support beam 2, there are four pairs, evenly and symmetrically distributed on both sides of mass block 3, and elastic support beam 2 is directly connected to mass block 3. Electrodes 4 and 5 are electrically insulated from mass block 3, and capacitors with appropriate spacing are designed between the electrodes and mass block. There are two sets of micro-lever amplification structures 6, which are symmetrically distributed. The input end of micro-lever 6 is directly connected to mass block 3, the support end is directly connected to the anchor point, and the output end is connected to stress output end 7. Stress output end 7 is connected to the resonant main structure R11 of resonator R1. The resonant main structure R11 of resonator R1 and the resonant main structure R21 of resonator R2 are connected through coupling structure 8. The other end of the resonant main structure R21 of resonator R2 is fixed to the anchor point.

[0070] Based on this single-axis sensor, a corresponding circuit system is built, such as... Figure 3 As shown in the figure, this figure is a specific circuit diagram of a feedback sensing method based on a weakly coupled resonant sensor provided in an embodiment of this application.

[0071] The circuit system includes: a transimpedance amplifier (TIA) 9 and an amplitude amplifier 10, a limiter 11, a bandpass filter (BPF) 12, a phase shifter 13, a voltage divider controller 14, two bias voltages 15 and 16, an analog-to-digital converter (ADC) 17, a multiplicative mixer 18, a low-pass filter (LPF) 19, a decoupling unit 20, a PI control module 21, a digitally controlled oscillator (NCO) 22, an amplitude ratio (AR) calculation module 23, an error calculation module 24, and a PI controller 25. The feedback signal generation module includes a bias voltage 26, a digital-to-analog converter (DAC) 27, and a voltage buffer 28.

[0072] Based on the circuit system constructed, see [link / reference]. Figure 4 The figure is a flowchart of another feedback sensing method based on a weakly coupled resonant sensor provided in this application embodiment. The sensing method includes:

[0073] S201: Apply the acceleration to be measured to the target sensor.

[0074] Among them, when the target is Figure 2When the acceleration signal to be measured is applied to anchor point 1 of the target sensor, the sensitive mass block 3 generates an inertial force due to its own mass and sensitivity to acceleration. By adjusting the voltage of the upper electrode 4, lower electrode 5, and sensitive mass block 3, the upper electrode 4 and lower electrode 5 can generate an electrostatic force on the sensitive mass block 3 in the sensitive axis direction. The resultant force of the inertial force and the electrostatic force acts on the micro-lever amplification structure 6, and the micro-lever amplifies this resultant force and transmits it to the stress output end 7. This resultant force is applied from the stress application end 7 to the resonator R1 of the weakly coupled resonator group, causing a slight stiffness perturbation in the resonator R1, changing the effective stiffness, and thus causing a modal localization effect.

[0075] Optionally, Figure 2 The driving electrodes R13 and R23 can be applied with voltage signals to excite the main resonator structures R1 and R2 to vibrate. This causes a change in capacitance between the main resonator structures R1 and R2 and the detection electrodes R14 and R24 on the other side, allowing a response current to be detected on the detection electrodes R14 and R24. The tuning electrodes R12 and R22 can apply a DC bias, generating an electrostatic negative stiffness effect on the main resonator structures R1 and R2, thus adjusting their resonant frequencies.

[0076] S202: Obtain the detection signal from the detection electrode of the target sensor.

[0077] Optionally, the response current can be detected from the detection electrodes R14 and R24 of the two resonators R1 and R2 of the target sensor to obtain the detection signal. Of course, other methods can also be used to obtain the detection signal without affecting the normal implementation of the embodiments of this application.

[0078] Optionally, the obtained detection signal can also be processed after... Figure 3 After passing through the transimpedance amplifier (TIA) 9, the signal can be quantized into a digital signal by the analog-to-digital converter (ADC) 17 for easier extraction of subsequent information. Of course, the detection signal can also be omitted without affecting the normal implementation of the embodiments of this application.

[0079] Optionally, the resonators R1 and R2 can be brought to the required initial operating state by using two bias voltages 15 and 16. This can not only compensate for the excessive mode frequency difference caused by process errors, but also allow the two resonators to be at different amplitude ratio bias points by adjusting the electrostatic negative stiffness.

[0080] Optionally, the detection signal detected by the resonator R2 can also be passed through the transimpedance amplifier (TIA) 9 and amplitude amplifier 10 connected to the electrodes, and then through the limiter 11 to the bandpass filter 12. After filtering out low-frequency noise and high-frequency noise, it is then passed through the phase shifter 13 and voltage divider controller 14 to the driving electrode of the resonator R2 to drive the resonator to vibrate at the resonant frequency, or to adjust the resonant frequency of the resonator.

[0081] S203: Extract information from the detection signal.

[0082] The extracted information may include amplitude or phase information corresponding to the detected signal. Optionally, the information in the detected signal can be extracted as follows: First, the two detected signals obtained from resonators R1 and R2 are multiplied by sinωt and cosωt respectively, and then multiplied by the multiplier mixer 18 to obtain two output signals. Then, after the two output signals are processed by the low-pass filter (LPF) 19, preliminary amplitude and phase information are obtained. Finally, the preliminary amplitude and phase information are processed by the decoupling unit 20 to obtain the amplitude and phase information in the detected signal.

[0083] Optionally, the processed phase information needs to enter the PI control module 21 and then pass through the digitally controlled oscillator (NCO) 22 to obtain the initial two sinωt and cosωt signals, so as to obtain the corresponding feedback voltage later.

[0084] S204: Generate a feedback voltage based on the extracted information and apply the feedback voltage to the target sensor.

[0085] Optionally, the feedback voltage can be generated and applied to the target sensor in the following manner: First, the obtained amplitude information is processed by the amplitude ratio calculation module 23 to obtain the amplitude ratio corresponding to the two detection signals. Then, it enters the error calculation module 24, which obtains the error information based on the comparison information between the amplitude ratio and the predetermined amplitude ratio reference point. Then, the PI controller 25 outputs a feedback voltage Vt based on the obtained error information and applies different bias voltages to the output feedback voltage. After conversion by the digital-to-analog converter (DAC) 27, the voltage is input to the voltage buffer 28 to obtain two bias voltages. Finally, the two bias voltages are applied to the upper electrode 4 and the lower electrode 5 respectively, converting the two bias voltages into an electrostatic force applied to the mass block 3. This electrostatic force is used to cancel the inertial force caused by acceleration on the mass block 3, so that the amplitude ratio of the detection signal is stabilized around the set amplitude ratio reference point. Of course, other methods can also be used to generate the feedback voltage without affecting the normal implementation of the embodiments of this application.

[0086] S205: Output feedback voltage as the test result.

[0087] The output feedback voltage can be the feedback voltage output by the PI controller 25.

[0088] In some possible implementations, the test results can be calculated as follows: Since the capacitance C1 between the upper electrode 4 and the mass block 3 is:

[0089]

[0090] Where x is the resonator vibration displacement, d is the initial distance between the upper electrode 4 and the lower electrode 5, A is the relative area between the upper electrode 4 and the lower electrode 5, and capacitance C0 represents the initial capacitance between the upper electrode 4 and the mass block 3.

[0091] Therefore, the electrostatic force F applied to the mass block by the upper electrode 4 with the applied bias voltage is... e1 for:

[0092]

[0093] Among them, V t For feedback voltage, V dc The bias voltage across the mass block is (V t +V bias ) is the bias voltage applied to the upper electrode 4.

[0094] Similarly, the capacitance C2 between the lower electrode 5 and the mass block 3 is:

[0095]

[0096] Therefore, the electrostatic force F applied by the lower electrode 5 with the applied bias voltage to the mass block 3 e2 for:

[0097]

[0098] Among them, (V) t –V bias ) is the bias voltage applied to the lower electrode 5.

[0099] Therefore, the electrostatic force F acting on the mass block e for:

[0100]

[0101] When the electrostatic force and the inertial force are in equilibrium, x = 0, therefore we can obtain:

[0102] F e =-m*Acc

[0103] Where m is the mass of mass block 3, and Acc is the acceleration to be measured.

[0104] Therefore, the acceleration Acc to be measured can be obtained as:

[0105]

[0106] In this embodiment, the acceleration to be measured is applied to the target sensor, and a detection signal is obtained through the sensor's detection electrodes. The information in the detection signal is used to generate a feedback voltage to counteract the inertial force exerted on the target sensor by the measured physical quantity. This feedback signal is then output as the test result. Using the feedback voltage as the output significantly widens the linear operating range, thereby greatly expanding the sensor's measurement range and eliminating the correlation between the sensitivity and range of the sensor's multi-degree-of-freedom weakly coupled resonator. Thus, without affecting the ultra-high sensitivity of the multi-degree-of-freedom weakly coupled resonator in the sensor, the sensor's detection range is greatly expanded.

[0107] The above are some specific implementations of the feedback sensing method based on a weakly coupled resonant sensor provided in the embodiments of this application. Based on this, this application also provides a corresponding device. The device provided in the embodiments of this application will be described below from the perspective of functional modularity.

[0108] See Figure 5 The diagram shows a feedback sensing device 300 based on a weakly coupled resonant sensor. The device 300 includes a disturbance signal receiving module 310, a resonant signal generating module 320, and a feedback signal generating module 330.

[0109] The disturbance signal receiving module 310 is used to receive disturbance signals. The disturbance signal is obtained by converting the physical quantity to be measured.

[0110] The resonant signal generation module 320 is used to input a disturbance signal into a target sensor so that the target sensor generates at least one resonant signal based on the disturbance signal.

[0111] The feedback signal generation module 330 is used to detect at least one resonant signal generated by the target sensor and generate a feedback signal based on the at least one resonant signal to balance the disturbance signal according to the feedback signal. The target sensor is a multi-degree-of-freedom weakly coupled resonant sensor.

[0112] The feedback signal output module 340 is used to output the feedback signal as a measurement result.

[0113] Optionally, the target sensor is a resonant sensor, wherein the target sensor includes multiple resonators, and the resonant signal generation module is also used to adjust the multiple mutually coupled resonators of the target sensor to the target vibration mode frequency, and then use a disturbance signal to cause the target sensor to undergo a mode localization effect, thereby generating at least one resonant signal.

[0114] Optionally, the feedback signal generation module is further configured to demodulate at least one resonant signal, and then determine the resonant signal information based on the demodulated resonant signal, wherein the resonant signal information includes the amplitude, amplitude ratio and amplitude difference corresponding to at least one resonant signal, and finally generate a feedback signal based on the resonant signal information.

[0115] As an example, the apparatus provided in this application embodiment can also be found in... Figure 6 As shown, Figure 6 This is another schematic diagram of a feedback sensing device based on a weakly coupled resonant sensor provided in an embodiment of this application. The device includes: a sensing unit, a modal localization effect unit, a resonator driving detection unit, and a closed-loop feedback control unit.

[0116] The sensitive unit is used to convert the input of the external physical quantity to be measured into a disturbance signal, and then apply the disturbance signal to the modal localization effect unit.

[0117] The modal localization effect unit utilizes the ultra-high sensitivity of the modal localization effect of weakly coupled resonators to stably amplify and modulate perturbation signals containing information about the measured physical quantity. The modal localization effect unit includes a multi-degree-of-freedom weakly coupled resonant sensor.

[0118] The resonator drive detection unit is used to enable the modal localization effect unit to meet the conditions required for modal localization effect, and to detect the resonant signals of one or more resonators in the modal localization effect unit, convert them into electrical signals, and complete the amplification and modulation of the physical quantity under test.

[0119] The closed-loop feedback control unit is used to demodulate and extract information from the resonant signal, and generate a feedback signal to act on the sensitive unit in order to balance the disturbance of the external physical quantity to be measured on the modal localization effect unit.

[0120] The sensing unit includes a measured physical quantity response module and a negative feedback execution module. The measured physical quantity response module stably converts the measured physical quantity into the input signal of the multi-degree-of-freedom weakly coupled resonant sensor. The negative feedback execution module stably converts the feedback signal into the input signal of the multi-degree-of-freedom weakly coupled resonant sensor, and within the sensor's measurement range, cancels out disturbances caused by the measured physical quantity.

[0121] The modal localization effect unit includes a weakly coupled resonator module, a driving module, a tuning module, and a detection and loading module. The weakly coupled resonator module consists of multiple mutually coupled weakly coupled resonators, and their coupling method can be mechanical coupling, electrostatic coupling, or a combination of both. Optionally, the weakly coupled resonator module can be designed using a differential configuration to further improve sensing accuracy and common-mode rejection ratio. The driving module is used to drive each resonator in the weakly coupled resonator to the desired vibration mode. The type of driving module can include electrostatic actuators, such as piezoelectric actuators, electromagnetic actuators, thermocouple actuators, and other actuators. For example, the driving module can be an electrostatic comb driver or an electrostatic parallel plate driver. The tuning module is used to adjust the frequency of the desired vibration mode of each resonator in the weakly coupled resonator. Of course, the tuning module can also be used to adjust to different bias points according to actual needs, all within the scope of protection of this application embodiment. The detection and loading module is used to detect the resonant signal of each resonator in the weakly coupled resonator.

[0122] The resonator drive detection unit includes a signal amplification module, an oscillation module, and a signal modulation module. The signal amplification module converts and amplifies the resonant signal output from the detection loading module into a voltage or current signal. The oscillation module controls the vibration mode frequencies of each resonator in the weakly coupled resonator; the oscillation module can be a phase-locked loop (PLL) circuit or a self-excited oscillation circuit. Optionally, an automatic gain control circuit can be added for more precise control. The signal modulation module processes the signal output from the oscillation module to generate a drive signal required by the drive module, such as increasing drive capability, impedance matching, inversion, differential drive, amplitude adjustment, or generating multiple drive signals. Simultaneously, the signal modulation module can also generate a tuning signal to be loaded into the tuning module without affecting the normal implementation of this embodiment.

[0123] The closed-loop feedback control unit includes an amplitude demodulation module, a signal processing module, a closed-loop control module, and a feedback signal generation module. The amplitude demodulation module demodulates the signal output from the resonator-driven detection unit to obtain a low-noise demodulated signal. The signal processing module performs calculations on the demodulated multi-channel signals, such as calculating the amplitude ratio or amplitude difference, to extract relevant information from the demodulated signals. The closed-loop control module maintains the stability of the entire device, controls the overall response speed of the device to the measured physical quantity, and generates a negative feedback control signal. Optionally, the closed-loop control module can also employ classical control methods, such as PID control, to control the device's response speed. Of course, modern control methods, such as optimal control, adaptive control, and robust control, can also be used without affecting the normal implementation of this embodiment. The feedback signal generation module generates a feedback signal based on the negative feedback control signal generated by the closed-loop control module to balance the disturbances applied to the target sensor by the measured physical quantity.

[0124] This application also provides a corresponding sensing system for implementing the solution provided in this application.

[0125] In the embodiments of this application, the terms "first" and "second" (if they exist) are used only as name identifiers and do not represent the order of first and second.

[0126] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general-purpose hardware platform. Based on this understanding, the technical solution of this application can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as a read-only memory (ROM) / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0127] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the apparatus embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. 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 creative effort.

[0128] The above description is merely an exemplary implementation of this application and is not intended to limit the scope of protection of this application.

Claims

1. A feedback type sensing method based on a weakly coupled resonant type sensor, characterized by, The method comprises: receiving a disturbance signal, the disturbance signal being converted from a physical quantity to be measured; inputting the disturbance signal into a target sensor, so that the target sensor generates at least one resonance signal according to the disturbance signal, the target sensor being a multi-degree-of-freedom weakly coupled resonant sensor; after detecting the at least one resonance signal generated by the target sensor, generating a feedback signal according to the at least one resonance signal, so as to balance the disturbance signal according to the feedback signal; the generating of the feedback signal according to the at least one resonance signal comprises: demodulating the at least one resonance signal respectively; determining resonance signal information according to the demodulated resonance signal, the resonance signal information comprising an amplitude, an amplitude ratio or an amplitude difference corresponding to the at least one resonance signal; generating a feedback signal according to the resonance signal information; the generating of the feedback signal according to the resonance signal information comprises: generating a negative feedback control signal according to the resonance signal information, the negative feedback control signal being used for controlling the balancing capability of the target sensor to the disturbance signal; generating a feedback signal according to the negative feedback control signal, so as to balance the disturbance signal; outputting the feedback signal as a measurement result.

2. The method of claim 1, wherein, The target sensor comprises a plurality of mutually coupled resonators, and the making of the target sensor generate at least one resonance signal according to the disturbance signal comprises: adjusting the plurality of mutually coupled resonators in the target sensor to a target vibration mode frequency; utilizing the disturbance signal to cause the target sensor to have a mode localization effect, so as to generate at least one resonance signal.

3. The method of claim 2, wherein, After the inputting of the disturbance signal into the target sensor, so that the target sensor generates at least one resonance signal according to the disturbance signal, the method further comprises: detecting an actual vibration mode frequency of the target sensor; generating a tuning voltage signal according to the actual vibration mode frequency, the tuning voltage signal being used for adjusting the vibration mode frequency required by the target sensor.

4. The method of claim 1, wherein, The balancing of the disturbance signal according to the feedback signal comprises: inputting the feedback signal into the target sensor; utilizing the feedback signal to offset the disturbance signal received by the target sensor, so that the amplitude, the amplitude ratio or the amplitude difference of the resonance signal generated by the target sensor returns to an initial value.

5. A feedback sensor device based on a weakly coupled resonant sensor, characterized in that The device is used for executing the feedback type sensing method based on the weakly coupled resonant sensor according to any one of claims 1-4, and the device comprises a disturbance signal receiving module, a resonance signal generating module, a feedback signal generating module and a feedback signal output module. The disturbance signal receiving module is used for receiving a disturbance signal, the disturbance signal being converted from a physical quantity to be measured; The resonance signal generating module is used for inputting the disturbance signal into a target sensor, so that the target sensor generates at least one resonance signal according to the disturbance signal, the target sensor being a multi-degree-of-freedom weakly coupled resonant sensor; The feedback signal generating module is used for, after detecting the at least one resonance signal generated by the target sensor, generating a feedback signal according to the at least one resonance signal, so as to balance the disturbance signal according to the feedback signal. The feedback signal generation module is configured to generate a feedback signal according to the at least one resonance signal after detecting the at least one resonance signal generated by the target sensor, so as to balance the disturbance signal according to the feedback signal; the generation of the feedback signal according to the at least one resonance signal comprises: demodulating the at least one resonance signal respectively; determining resonance signal information according to the demodulated resonance signal, wherein the resonance signal information comprises an amplitude, an amplitude ratio or an amplitude difference corresponding to the at least one resonance signal; and generating the feedback signal according to the resonance signal information; the generation of the feedback signal according to the resonance signal information comprises: generating a negative feedback control signal according to the resonance signal information, wherein the negative feedback control signal is used to control the balancing capability of the target sensor to the disturbance signal; and generating the feedback signal according to the negative feedback control signal, so as to balance the disturbance signal. The feedback signal output module is configured to output the feedback signal as a measurement result.

6. The apparatus of claim 5, wherein, The target sensor comprises a plurality of mutually coupled resonators, and the resonance signal generation module is further configured to adjust the plurality of mutually coupled resonators of the target sensor to a target vibration modal frequency, and then utilize the disturbance signal to cause the target sensor to have a modal localization effect, so as to generate the at least one resonance signal.

7. A sensing system characterized by, The sensing system applies the feedback sensing method based on the weakly coupled resonant sensor according to any one of claims 1-4.

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