Integrated Angular Velocity Sensor and Its Signal Fusion Method

Abstract

The present invention provides an integrated angular velocity sensor and a signal fusion method thereof, which relates to the technical field of instruments and meters. The signal fusion method includes: using an angular velocity sensor and a gyroscope to collect signals with unknown angular velocity to obtain a first output voltage and a second output voltage; inputting the first output voltage and the second output voltage into a processor to respectively output a first angular velocity signal and a second angular velocity signal, and superimposing them to obtain a superimposed angular velocity signal; inputting the superimposed angular velocity signal into a plurality of candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters; using a comparator to compare the plurality of gains with each other, and determining the candidate band-pass filter corresponding to the maximum gain as the target band-pass filter; using the target band-pass filter to process the superimposed angular velocity signal, and based on the frequency band where the filtered superimposed angular velocity signal is located, selecting a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located for fusion to obtain a fusion signal.

Description

Technical Field

[0001] The present invention relates to the technical field of instruments and meters, and more specifically, to an integrated angular velocity sensor and a signal fusion method thereof. Background Art

[0002] The angular velocity sensor based on Magnetohydrodynamics (MHD) has the advantages of wide bandwidth, low noise, shock resistance, and small volume. It can achieve sub-μrad level measurement of angular vibration in the kHz frequency band, and is currently the most suitable component for on-orbit angular velocity measurement, which is of great significance to the development of sensitive payloads such as long-distance laser communication and geostationary orbit remote sensing imaging. However, the MHD angular velocity sensor has a principle limit. When the angular rotation frequency is low, under the action of back electromotive force and viscous force, the output performance is not good, and it cannot meet the wide-band measurement requirements of angular velocity from 0.1 Hz to 1 kHz when used alone.

[0003] Fusing the signals of a gyroscope with good low-frequency performance and the MHD angular velocity sensor can correct the low-frequency error of the sensor without affecting the stability of the sensor, and realize the bandwidth expansion. Currently, in the research on signal fusion algorithms, signal fusion is studied based on the separate installation of the gyroscope and the MHD angular velocity sensor. The separate installation method has low integration, a large signal transmission loop area, is easy to introduce external noise interference, and the angular velocity measurement has uncertainty. Summary of the Invention

[0004] To solve at least one of the technical problems in the prior art, an embodiment of the present invention provides an integrated angular velocity sensor and a signal fusion method thereof, which reduce the uncertainty of angular velocity measurement.

[0005] The present invention provides a signal fusion method based on an integrated angular velocity sensor. The integrated angular velocity sensor includes an angular velocity sensor based on magnetohydrodynamics, a gyroscope coaxially installed with the angular velocity sensor, and a signal fusion circuit. The signal fusion circuit is electrically connected to the angular velocity sensor and the gyroscope. A processor is provided on the signal fusion circuit, and a plurality of candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit, and the signal fusion method includes: using the angular velocity sensor and the gyroscope to collect signals with unknown angular velocity input from the outside to obtain a first output voltage of the angular velocity sensor and a second output voltage of the gyroscope; inputting the first output voltage and the second output voltage into the processor to respectively output a first angular velocity signal of the angular velocity sensor and a second angular velocity signal of the gyroscope; superimposing the first angular velocity signal and the second angular velocity signal to obtain a superimposed angular velocity signal; inputting the superimposed angular velocity signal into a plurality of the candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters; using the comparator to compare the plurality of gains with each other, and determining the candidate band-pass filter corresponding to the largest gain among the plurality of gains as the target band-pass filter; using the target band-pass filter to process the superimposed angular velocity signal, and selecting a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located based on the frequency band of the filtered superimposed angular velocity signal for fusion to obtain a fusion signal.

[0006] Optionally, the step of inputting the first output voltage and the second output voltage into the processor to respectively output the first angular velocity signal of the angular velocity sensor and the second angular velocity signal of the gyroscope includes: inputting the signal with unknown angular velocity into the processor to determine a first scale factor of the angular velocity sensor and a second scale factor of the gyroscope; inputting the first output voltage and the first scale factor into the processor to calculate and obtain the first angular velocity signal; inputting the second output voltage and the second scale factor into the processor to calculate and obtain the second angular velocity signal.

[0007] Optionally, the candidate band-pass filters are constructed based on a first cut-off frequency of the angular velocity sensor, a second cut-off frequency of the gyroscope, and an intersection frequency point between the first cut-off frequency and the second cut-off frequency. The intersection frequency point is used as the center frequency of the candidate band-pass filter, and the center frequencies of the plurality of candidate band-pass filters are different from each other.

[0008] Optionally, inputting the superimposed angular velocity signal into the multiple candidate band-pass filters to obtain the gains corresponding to the multiple candidate band-pass filters respectively includes: inputting the superimposed angular velocity signal into the multiple candidate band-pass filters, and calculating the root mean square values through multiple sliding windows corresponding to the multiple candidate band-pass filters respectively, so as to obtain the gains corresponding to the multiple candidate band-pass filters respectively.

[0009] Optionally, processing the superimposed angular velocity signal by using the target band-pass filter, and based on the frequency band where the filtered superimposed angular velocity signal is located, selecting a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located for fusion to obtain a fusion signal includes: when the filtered superimposed angular velocity signal is in the frequency band of 0.1 Hz to 1 Hz, selecting Kalman filtering for fusion to obtain the fusion signal; when the filtered superimposed angular velocity signal is in the frequency band of 1 Hz to 20 Hz, selecting adaptive Kalman filtering for fusion to obtain the fusion signal; when the filtered superimposed angular velocity signal is in the frequency band of 20 Hz to 1000 Hz, selecting complementary filtering for fusion to obtain the fusion signal.

[0010] Optionally, the transfer function of the angular velocity sensor and the transfer function of the gyroscope are constructed through the following steps: respectively testing multiple scale factors and multiple phase information of the angular velocity sensor and the gyroscope under different frequencies; using a model fitting function, based on the multiple scale factors and multiple phase information of the angular velocity sensor and the multiple scale factors and multiple phase information of the gyroscope, respectively obtaining the transfer function of the angular velocity sensor and the transfer function of the gyroscope.

[0011] According to an embodiment of another aspect of the present invention, an integrated angular velocity sensor is further provided for implementing the signal fusion method based on the integrated angular velocity sensor. The integrated angular velocity sensor includes: a housing; a cylinder installed in the housing; an angular velocity sensor based on magnetohydrodynamics installed in the cylinder, the angular velocity sensor being configured to output a first output voltage in response to a signal with an unknown angular velocity input from the outside; a gyroscope installed above the angular velocity sensor and coaxially arranged with the angular velocity sensor, the gyroscope being configured to output a second output voltage in response to the signal with the unknown angular velocity; a signal fusion circuit installed above the gyroscope and electrically connected to the angular velocity sensor and the gyroscope, the signal fusion circuit being configured to obtain a fusion signal based on the first output voltage and the second output voltage.

[0012] Optionally, the above signal fusion circuit includes: a signal acquisition unit electrically connected to the above angular velocity sensor and the above gyroscope, the signal acquisition unit being configured to acquire the above first output voltage and the above second output voltage; a processor, including: a first signal processing unit electrically connected to the signal acquisition unit, the first signal processing unit being configured to respectively output a first angular velocity signal of the angular velocity sensor and a second angular velocity signal of the gyroscope based on the above first output voltage and the above second output voltage; a second signal processing unit electrically connected to the first signal processing unit, the second signal processing unit being configured to superimpose the above first angular velocity signal and the above second angular velocity signal to obtain a superimposed angular velocity signal, and input the superimposed angular velocity signal into a plurality of candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters; a third signal processing unit electrically connected to the second signal processing unit, the third signal processing unit being configured to compare the plurality of gains with each other by using a comparator, and determine the candidate band-pass filter corresponding to the largest gain among the plurality of gains as the target band-pass filter; a signal output unit electrically connected to the third signal processing unit, the signal output unit being configured to process the superimposed angular velocity signal by using the target band-pass filter, and select a fusion algorithm matching the frequency band where the filtered superimposed angular velocity signal is located for fusion to obtain a fusion signal.

[0013] Optionally, the integrated angular velocity sensor further includes: a signal detection circuit installed in the above cylinder and located above the angular velocity sensor, the signal detection circuit being configured to amplify the above first output voltage output by the angular velocity sensor.

[0014] According to an embodiment of another aspect of the present invention, a system for measuring angular velocity is provided, including: a vibration isolation table fixed on the ground; an angular vibration table provided on the above vibration isolation table, the angular vibration table being configured to generate angular vibration in response to a control signal issued by a controller; an integrated angular velocity sensor provided on the above angular vibration table, the integrated angular velocity sensor being configured to obtain a fusion signal by executing the above signal fusion method based on the above angular vibration; a controller provided on the above ground and electrically connected to the above angular vibration table and the above integrated angular velocity sensor, the controller being configured to acquire the above fusion signal and compare the above fusion signal with the angular velocity of the angular vibration generated by the above angular vibration table, so as to perform error analysis.

[0015] An integrated angular velocity sensor and its signal fusion method according to an embodiment of the present invention. The integrated angular velocity sensor includes an angular velocity sensor based on magnetohydrodynamics, a gyroscope coaxially installed with the angular velocity sensor, and a signal fusion circuit, which reduces the signal transmission loop area and avoids introducing external noise interference. The signal fusion circuit is electrically connected to the angular velocity sensor and the gyroscope. A processor is provided on the signal fusion circuit, and multiple candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit. The angular velocity sensor and the gyroscope are used to collect signals with unknown angular velocity input from the outside to obtain the first output voltage of the angular velocity sensor and the second output voltage of the gyroscope. The first output voltage and the second output voltage are input into the processor to respectively output the first angular velocity signal of the angular velocity sensor and the second angular velocity signal of the gyroscope. The first angular velocity signal and the second angular velocity signal are superimposed to obtain a superimposed angular velocity signal. The superimposed angular velocity signal is input into multiple candidate band-pass filters to respectively obtain gains corresponding to the multiple candidate band-pass filters. The comparators are used to compare the multiple gains with each other, and the candidate band-pass filter corresponding to the largest gain among the multiple gains is determined as the target band-pass filter. The target band-pass filter is used to process the superimposed angular velocity signal, and based on the frequency band where the filtered superimposed angular velocity signal is located, a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located is selected for fusion to obtain a fusion signal. Multiple frequency bands adaptively select appropriate fusion algorithms for signal fusion, reducing the uncertainty of angular velocity measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flowchart of a signal fusion method based on an integrated angular velocity sensor according to an embodiment of the present invention;

[0017] Figure 2 is a software simulation diagram of a signal fusion method based on an integrated angular velocity sensor according to an embodiment of the present invention;

[0018] Figure 3 is a three-dimensional cross-sectional view of an MHD angular velocity sensor according to an embodiment of the present invention;

[0019] Figure 4 is an amplitude-frequency response curve diagram of an MHD angular velocity sensor and a gyroscope according to an embodiment of the present invention;

[0020] Figure 5 is a frequency response curve diagram of three candidate band-pass filters according to an embodiment of the present invention;

[0021] Figure 6 is a flowchart of sub-steps for outputting the first angular velocity signal of the MHD angular velocity sensor and the second angular velocity signal of the gyroscope according to an embodiment of the present invention;

[0022] Figure 7 is a block diagram of frequency band estimation according to an embodiment of the present invention;

[0023] Figure 8 is a cross-sectional view of an integrated angular velocity sensor according to an embodiment of the present invention;

[0024] Figure 9 is a block diagram of a signal fusion circuit according to an embodiment of the present invention;

[0025] Figure 10 is a block diagram of a signal detection circuit according to an embodiment of the present invention;

[0026] Figure 11 is a schematic diagram of a system for measuring angular velocity according to an embodiment of the present invention.

[0027] In the said drawings, the meanings of the reference numerals are specifically as follows:

[0028] 1. Housing;

[0029] 2. Cylinder;

[0030] 3. MHD angular velocity sensor;

[0031] 31. Top cover;

[0032] 32. Outer shell;

[0033] 33. End cover;

[0034] 34. Intermediate shaft sleeve;

[0035] 35. Inner insulating layer;

[0036] 36. Outer insulating layer;

[0037] 37. First spacer;

[0038] 38. Second spacer;

[0039] 39. Conductive fluid;

[0040] 310. Permanent magnet;

[0041] 311. First electrode;

[0042] 312. Second electrode;

[0043] 4. Gyroscope;

[0044] 5. Encapsulated circuit board;

[0045] 6. Signal detection circuit;

[0046] 7. Signal fusion circuit;

[0047] 8. Conductor;

[0048] 9. Conductive column;

[0049] 10. Connector;

[0050] 11. Preamplifier circuit;

[0051] 12. Low-pass filter circuit;

[0052] 13. Single-ended to differential circuit;

[0053] 14. AC coupling circuit;

[0054] 15. Threaded hole;

[0055] 16. Integrated angular velocity sensor;

[0056] 17. Angular vibration table;

[0057] 18. Vibration isolation table;

[0058] 19. Controller;

[0059] 20. Platform. Detailed implementation manners

[0060] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, many specific details are set forth in order to provide a comprehensive understanding of the embodiments of the present invention. However, it is obvious that one or more embodiments can be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of the present invention.

[0061] The terms used herein are merely for the purpose of describing specific embodiments and are not intended to limit the present invention. The terms "including", "comprising" and the like used herein indicate the presence of the described features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0062] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0063] In the case of using expressions such as "at least one of A, B, and C, etc.", generally, it should be interpreted according to the meaning that those skilled in the art usually understand this expression (for example, "a system having at least one of A, B, and C" should include, but not be limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", generally, it should be interpreted according to the meaning that those skilled in the art usually understand this expression (for example, "a system having at least one of A, B, or C" should include, but not be limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0064] To solve the problems of low integration of the separate installation of the angular velocity sensor and the gyroscope, large signal transmission loop area, easy introduction of external noise interference, and uncertainty in angular velocity measurement after signal fusion, according to the inventive concept of one aspect of the present invention, the integrated angular velocity sensor includes an angular velocity sensor based on magnetohydrodynamics and a gyroscope coaxially installed with the angular velocity sensor, as well as a signal fusion circuit, which reduces the signal transmission loop area and avoids introducing external noise interference. The signal fusion circuit is electrically connected to the angular velocity sensor and the gyroscope, and a processor is provided on the signal fusion circuit. A plurality of candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit. The angular velocity sensor and the gyroscope are used to collect signals with unknown angular velocity input from the outside to obtain the first output voltage of the angular velocity sensor and the second output voltage of the gyroscope. The first output voltage and the second output voltage are input into the processor, and the first angular velocity signal of the angular velocity sensor and the second angular velocity signal of the gyroscope are respectively output. The first angular velocity signal and the second angular velocity signal are superimposed to obtain a superimposed angular velocity signal. The superimposed angular velocity signal is input into a plurality of candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters. The comparators are used to compare the plurality of gains with each other, and the candidate band-pass filter corresponding to the largest gain among the plurality of gains is determined as the target band-pass filter. The target band-pass filter is used to process the superimposed angular velocity signal, and based on the frequency band where the filtered superimposed angular velocity signal is located, a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located is selected for fusion to obtain a fusion signal. Appropriate fusion algorithms are adaptively selected for signal fusion in multiple frequency bands, reducing the uncertainty of angular velocity measurement.

[0065] Figure 1 is a flowchart of a signal fusion method based on an integrated angular velocity sensor according to an embodiment of the present invention, Figure 8 is a cross-sectional view of an integrated angular velocity sensor according to an embodiment of the present invention.

[0066] A signal fusion method based on an integrated angular velocity sensor according to an embodiment of the present invention, as Figure 8 shown, the integrated angular velocity sensor 16 includes an angular velocity sensor based on magnetohydrodynamics (MHD angular velocity sensor 3), a gyroscope 4 coaxially mounted with the MHD angular velocity sensor 3, and a signal fusion circuit 7. The signal fusion circuit 7 is electrically connected to the MHD angular velocity sensor 3 and the gyroscope 4, and a processor is provided on the signal fusion circuit 7. A plurality of candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit 7, as Figure 1 shown, the signal fusion method includes the following steps S1 to S6.

[0067] Step S1: Use the MHD angular velocity sensor 3 and the gyroscope 4 to collect signals with unknown angular velocity input from the outside to obtain the first output voltage of the MHD angular velocity sensor 3 and the second output voltage of the gyroscope 4.

[0068] Step S2: Input the first output voltage and the second output voltage into the processor, and output the first angular velocity signal of the MHD angular velocity sensor 3 and the second angular velocity signal of the gyroscope 4 respectively.

[0069] Step S3: Superimpose the first angular velocity signal and the second angular velocity signal to obtain a superimposed angular velocity signal.

[0070] Step S4: Input the superimposed angular velocity signal into a plurality of candidate band-pass filters to obtain gains corresponding to the plurality of candidate band-pass filters respectively.

[0071] Step S5: Use the comparator to compare the plurality of gains with each other, and determine the candidate band-pass filter corresponding to the largest gain among the plurality of gains as the target band-pass filter.

[0072] Step S6: Process the superimposed angular velocity signal using the target band-pass filter, and select a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located based on the frequency band where the filtered superimposed angular velocity signal is located for fusion to obtain a fusion signal.

[0073] Figure 2 is a software simulation diagram of a signal fusion method based on an integrated angular velocity sensor according to an embodiment of the present invention.

[0074] According to an embodiment of the present invention, as Figure 2 shown, first, the software simulates a turntable to generate a rotation signal (unknown angular velocity). The MHD angular velocity sensor 3 and the gyroscope 4 simultaneously collect the rotation signal and superimpose it to obtain a superimposed angular velocity signal. The superimposed angular velocity signal is respectively input into a plurality of band-pass filters (as Figure 2The band-pass filters 1, 2, and 3) are processed and the processed multiple signals are input to a comparator to compare the maximum gain signal, that is, the output signal of the band-pass filter with the maximum gain. The signals in the corresponding frequency bands are input to the input ports of the corresponding fusion algorithms through a fusion selector. When the filtered superimposed angular velocity signal is in the frequency band of 0.1 Hz to 1 Hz (low-frequency band), Kalman filtering is selected for fusion. When the filtered superimposed angular velocity signal is in the frequency band of 1 Hz to 20 Hz (medium-frequency band), adaptive Kalman filtering is selected for fusion. When the filtered superimposed angular velocity signal is in the frequency band of 20 Hz to 1000 Hz (high-frequency band), complementary filtering is selected for fusion and is fused with the input signal of the MHD angular velocity sensor 3 and the input signal of the gyroscope 4, and the fused signal is output to an oscilloscope for observation.

[0075] Figure 3 is a three-dimensional cross-sectional view of an MHD angular velocity sensor according to an embodiment of the present invention.

[0076] According to an embodiment of the present invention, as Figure 3As shown in the figure, the MHD angular velocity sensor 3 includes a top cover 31, a housing 32, an end cover 33, an intermediate shaft sleeve 34, an inner insulating layer 35, an outer insulating layer 36, a first spacer 37, a second spacer 38, a conductive fluid 39, a permanent magnet 310, a first electrode 311, and a second electrode 312. The permanent magnet 310 is a radially magnetized ring structure for providing the static magnetic field required for the normal operation of the MHD angular velocity sensor 3. The inner insulating layer 35 is disposed outside the permanent magnet 310. The cross-section of the inner insulating layer 35 is L-shaped, and the permanent magnet 310 is embedded in the groove on the outer wall of the inner insulating layer 35. The first electrode 311 is a ring structure. The upper end surface of the first electrode 311 is flush with the upper end surface of the inner insulating layer 35. A through hole is provided on the first electrode 311 for filling the conductive fluid 39. The inner wall surface of the first electrode 311 and the outer wall surface of the inner insulating layer 35 are fixed by gluing. The outer insulating layer 36 is disposed outside the first electrode 311. The upper end surface of the outer insulating layer 36 is flush with the upper end surface of the inner insulating layer 35. The outer wall surface of the first electrode 311 and the inner wall surface of the outer insulating layer 36 are fixed by gluing. A stepped groove is provided on the outside of the outer insulating layer 36. The outer wall surface of the first electrode 311 and the inner wall surface of the outer insulating layer 36 are fixed by gluing. The second electrode 312 is a ring structure and is embedded in the stepped hole on the outside of the outer insulating layer 36. The outer wall surface of the second electrode 312 and the inner wall surface of the outer insulating layer 36 are fixed by gluing. The inner wall surface of the second electrode 312 and the outer wall surface of the inner insulating layer 35 are fixed by gluing. The conductive fluid 39 is filled into the annular closed cavity formed by the inner insulating layer 35, the outer insulating layer 36, the first electrode 311, and the second electrode 312 through the through hole on the first electrode 311. The intermediate shaft sleeve 34 is disposed inside the permanent magnet 310. The outer wall surface of the intermediate shaft sleeve 34 is in transitional fit with the inner wall surface of the permanent magnet 310. The material of the intermediate shaft sleeve 34 is soft magnetic alloy. The top cover 31, the housing 32, and the end cover 33 are disposed on the outermost side of the angular velocity sensor, and the material is soft magnetic alloy, forming a closed magnetic circuit with the intermediate shaft sleeve 34. Four threaded holes (not shown in the figure) are provided on the top cover 31. The first spacer 37 and the second spacer 38 are used for fixing the components inside the MHD angular velocity sensor 3.

[0077] According to an embodiment of the present invention, when the carrier rotates, the conductive fluid 39 remains relatively stationary with respect to the inertial space due to its fluidity and inertia, and forms a relative flow velocity with the rotational magnetic flux generated by the permanent magnet 310, thereby inducing a motional electromotive force proportional to the input angular velocity between the first electrode 311 and the second electrode 312.

[0078] According to an embodiment of the present invention, after the MHD angular velocity sensor 3 is designed, a multi-physics field coupling analysis method is used for simulation analysis to verify its design indexes. First, a magnetic field simulation based on MAXWELL is carried out. The three-dimensional structure of the MHD angular velocity sensor 3 is imported into MAXWELL, the balloon boundary condition is set, no current and voltage excitation sources are added, tetrahedral meshes are used for mesh division, and the magnetic field distribution inside the MHD angular velocity sensor 3 is obtained by solving. Then, a coupled simulation of the magnetic field, flow field, and electric field based on FLUENT is carried out. The upper and lower walls of the fluid channel are set to be conductive, the inner and outer walls are insulated and stationary relative to the relative rotation coordinate system. A custom function is used to simulate the sinusoidal motion sensitive in the actual operation of the MHD angular velocity sensor 3, and the weak voltage signal output by the MHD angular velocity sensor 3 is obtained by solving. Further, the output frequency response characteristic of the MHD angular velocity sensor 3 is obtained to verify the design result.

[0079] According to an embodiment of the present invention, based on the low-frequency error modeling of the MHD angular velocity sensor 3 and comprehensive consideration of various factors such as measurement bandwidth, output amplitude, sensor volume, magnetic field interference, temperature compensation, and noise suppression, the selection is completed, and the gyroscope 4 is used to complete the low-frequency measurement compensation of the MHD angular velocity sensor 3.

[0080] According to an embodiment of the present invention, the integrated angular velocity sensor 16 includes an MHD angular velocity sensor 3, a gyroscope 4 coaxially installed with the MHD angular velocity sensor 3, and a signal fusion circuit 7, which reduces the signal transmission loop area and avoids introducing external noise interference. The signal fusion circuit 7 is electrically connected to the MHD angular velocity sensor 3 and the gyroscope 4. A processor is provided on the signal fusion circuit 7, and a plurality of candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit 7. The MHD angular velocity sensor 3 and the gyroscope 4 are used to collect signals with unknown angular velocity input from the outside to obtain the first output voltage of the MHD angular velocity sensor 3 and the second output voltage of the gyroscope 4. The first output voltage and the second output voltage are input into the processor, and the first angular velocity signal of the MHD angular velocity sensor 3 and the second angular velocity signal of the gyroscope 4 are respectively output. The first angular velocity signal and the second angular velocity signal are superimposed to obtain a superimposed angular velocity signal. The superimposed angular velocity signal is input into a plurality of candidate band-pass filters, and the gains corresponding to the plurality of candidate band-pass filters are respectively obtained. The comparators are used to compare the plurality of gains with each other, and the candidate band-pass filter corresponding to the largest gain among the plurality of gains is determined as the target band-pass filter. The target band-pass filter is used to process the superimposed angular velocity signal, and based on the frequency band where the filtered superimposed angular velocity signal is located, a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located is selected for fusion to obtain a fusion signal. Appropriate fusion algorithms are adaptively selected for signal fusion in multiple frequency bands, reducing the uncertainty of angular velocity measurement.

[0081] According to an embodiment of the present invention, the transfer functions of the MHD angular velocity sensor 3 and the gyroscope 4 are constructed through the following steps: First, a plurality of scale factors and a plurality of phase information of the MHD angular velocity sensor 3 and the gyroscope 4 are respectively tested under different frequencies. Then, using a model fitting function, based on the plurality of scale factors and the plurality of phase information of the MHD angular velocity sensor 3 and the plurality of scale factors and the plurality of phase information of the gyroscope 4, the transfer functions of the MHD angular velocity sensor 3 and the gyroscope 4 are respectively obtained.

[0082] According to an embodiment of the present invention, a plurality of scale factors and a plurality of phase information of the MHD angular velocity sensor 3 and the gyroscope 4 are respectively tested through experiments under different frequencies, and then using a model fitting function, based on the plurality of scale factors and the plurality of phase information of the MHD angular velocity sensor 3 and the plurality of scale factors and the plurality of phase information of the gyroscope 4, the transfer function G MHD (s) of the MHD angular velocity sensor 3 and the transfer function G MEMS (s) of the gyroscope 4 are respectively obtained. According to the transfer function G MHD (s) of the MHD angular velocity sensor 3 and the transfer function G MEMS (s) of the gyroscope 4, an amplitude-frequency response curve graph is plotted, and a mathematical model of the MHD angular velocity sensor 3 and a mathematical model of the gyroscope 4 are established.

[0083] According to an embodiment of the present invention, the transfer function G MHD (s) of the MHD angular velocity sensor 3 and the transfer function G MEMS (s) of the gyroscope 4 are respectively constructed based on the plurality of scale factors and the plurality of phase information of the MHD angular velocity sensor 3 and the plurality of scale factors and the plurality of phase information of the gyroscope 4, so as to be called when the scale factors of the subsequent MHD angular velocity sensor 3 and the scale factors of the gyroscope 4 are unified.

[0084] According to an embodiment of the present invention, the candidate band-pass filter is constructed based on the first cut-off frequency of the MHD angular velocity sensor 3, the second cut-off frequency of the gyroscope 4, and the intersection frequency point between the first cut-off frequency and the second cut-off frequency. The intersection frequency point is used as the center frequency of the candidate band-pass filter, and the center frequencies of the plurality of candidate band-pass filters are different from each other.

[0085] Figure 4 is the amplitude-frequency response curve graph of the MHD angular velocity sensor and the gyroscope according to an embodiment of the present invention, Figure 5 is the frequency response curve graph of three candidate band-pass filters according to an embodiment of the present invention.

[0086] According to an embodiment of the present invention, as Figure 4 shownFigure 4 Among them, curve A is the amplitude-frequency response curve of the MHD angular velocity sensor 3, Figure 4 and curve B is the amplitude-frequency response curve of the gyroscope 4. The -3dB value of the amplitude-frequency response curve is taken as the cut-off frequency of the MHD angular velocity sensor 3 and the gyroscope 4. Then, three candidate band-pass filters (BPF1, BPF2, and BPF3) are established respectively according to the first cut-off frequency of the MHD angular velocity sensor 3 (the first cut-off frequency is the low-frequency cut-off frequency), the second cut-off frequency of the gyroscope 4 (the second cut-off frequency is the high-frequency cut-off frequency), and the intersection frequency point of the MHD angular velocity sensor 3 and the gyroscope 4 as the center frequency. As Figure 5 shown, Figure 5 Among them, curve BPF1 is the first candidate band-pass filter (BPF1) established according to the first cut-off frequency of the MHD angular velocity sensor 3, Figure 5 curve BPF2 is the second candidate band-pass filter (BPF2) established according to the second cut-off frequency of the gyroscope 4, Figure 5 and curve BPF3 is the third candidate band-pass filter (BPF3) established with the intersection frequency point of the MHD angular velocity sensor 3 and the gyroscope 4 as the center frequency. The first scale factor k of the MHD angular velocity sensor 3 at 10 Hz frequency is obtained and recorded through experimental tests MHD and the second scale factor k of the gyroscope 4 at 0.1 Hz frequency. MEMS .

[0087] According to an embodiment of the present invention, the MHD angular velocity sensor 3 is used to measure high-frequency angular vibration information, the gyroscope 4 is used to measure low-frequency angular vibration information, and the gyroscope 4 is used to complete the low-frequency measurement compensation for the MHD angular velocity sensor 3, so that the integrated angular velocity sensor 16 can achieve wide-band angular velocity measurement from 0.1 Hz to 1 kHz.

[0088] Figure 6 is a flowchart of the sub-steps of outputting the first angular velocity signal of the MHD angular velocity sensor and the second angular velocity signal of the gyroscope according to an embodiment of the present invention, Figure 7 is a block diagram of frequency band estimation according to an embodiment of the present invention.

[0089] According to an embodiment of the present invention, as Figure 6 shown, it includes the following steps S21 to step S23.

[0090] Step S21: Input the signal with unknown angular velocity into the processor to determine the first scale factor of the MHD angular velocity sensor 3 and the second scale factor of the gyroscope 4.

[0091] According to an embodiment of the present invention, the first scale factor is the first scale factor k of the MHD angular velocity sensor 3 at the 10 Hz frequency of the constructed mathematical model of the MHD angular velocity sensor 3 MHD , and the second scale factor is the second scale factor k of the gyroscope 4 at the 0.1 Hz frequency of the constructed mathematical model of the gyroscope 4 MEMS .

[0092] Step S22: Input the first output voltage and the first scale factor into the processor to calculate the first angular velocity signal.

[0093] According to an embodiment of the present invention, as Figure 7 shown, use the MHD angular velocity sensor 3 to collect the signal with unknown angular velocity input from the outside to obtain the first output voltage U of the MHD angular velocity sensor 3 MHD , divide the first output voltage U MHD by the first scale factor k MHD to obtain the first angular velocity signal ω MHD .

[0094] Step S23: Input the second output voltage and the second scale factor into the processor to calculate the second angular velocity signal.

[0095] According to an embodiment of the present invention, as Figure 7 shown, use the gyroscope 4 to collect the signal with unknown angular velocity input from the outside to obtain the second output voltage U of the gyroscope 4 MEMS , divide the second output voltage U MEMS by the second scale factor k MEMS to obtain the second angular velocity signal ω MEMS .

[0096] According to an embodiment of the present invention, by dividing the first output voltage by the first scale factor and dividing the second output voltage by the second scale factor, the scale factors of the MHD angular velocity sensor 3 and the gyroscope 4 are unified.

[0097] According to an embodiment of the present invention, input the superimposed angular velocity signal into multiple candidate band-pass filters, and the gains corresponding to the multiple candidate band-pass filters are obtained respectively, including: input the superimposed angular velocity signal into multiple candidate band-pass filters, and calculate the root mean square values through multiple sliding windows corresponding to the multiple candidate band-pass filters respectively, and obtain the gains corresponding to the multiple candidate band-pass filters respectively.

[0098] According to an embodiment of the present invention, as Figure 7 shown, the first angular velocity signal ω MHD and the second angular velocity signal ω MEMSPerform superposition to obtain a superimposed angular velocity signal. Input the superimposed angular velocity signal into three candidate band-pass filters (BPF1, BPF2, and BPF3), and calculate the root mean square value through three sliding windows corresponding to the three candidate band-pass filters respectively, to obtain gains corresponding to the three candidate band-pass filters respectively. Input the three gains into a comparator for judgment and comparison, and determine the candidate band-pass filter corresponding to the largest gain among the three gains as the target band-pass filter, thereby completing the frequency band estimation.

[0099] According to an embodiment of the present invention, use the target band-pass filter to process the superimposed angular velocity signal, and based on the frequency band where the filtered superimposed angular velocity signal is located, select a fusion algorithm that matches the frequency band where the superimposed angular velocity signal is located for fusion to obtain a fusion signal, including: when the filtered superimposed angular velocity signal is in the frequency band of 0.1 Hz to 1 Hz, select Kalman filter for fusion to obtain a fusion signal; when the filtered superimposed angular velocity signal is in the frequency band of 1 Hz to 20 Hz, select adaptive Kalman filter for fusion to obtain a fusion signal; when the filtered superimposed angular velocity signal is in the frequency band of 20 Hz to 1000 Hz, select complementary filter for fusion to obtain a fusion signal.

[0100] According to an embodiment of the present invention, when the frequency band estimation shows that the filtered superimposed angular velocity signal is in the frequency band of 0.1 Hz to 1 Hz (low frequency band), selecting Kalman filter for fusion can achieve a better signal fusion effect. When the frequency band estimation shows that the filtered superimposed angular velocity signal is in the frequency band of 1 Hz to 20 Hz (medium frequency band), selecting adaptive Kalman filter for fusion can achieve a better signal fusion effect. When the frequency band estimation shows that the filtered superimposed angular velocity signal is in the frequency band of 20 Hz to 1000 Hz (high frequency band), selecting complementary filter for fusion can achieve a better signal fusion effect. Introducing frequency band estimation, estimating the frequency band where the superimposed angular velocity signal is located, and adaptively selecting an appropriate fusion algorithm for signal fusion can achieve wide-band angular velocity measurement from 0.1 Hz to 1 kHz, and reduce the uncertainty of angular velocity measurement.

[0101] According to another embodiment of the present invention, as Figure 8As shown, an integrated angular velocity sensor 16 is provided for implementing the above signal fusion method based on the integrated angular velocity sensor. The integrated angular velocity sensor 16 includes a housing 1, a cylinder 2, an MHD angular velocity sensor 3, a gyroscope 4, and a signal fusion circuit 7. The cylinder 2 is installed inside the housing 1. The MHD angular velocity sensor 3 is installed inside the cylinder 2, and the MHD angular velocity sensor 3 is configured to output a first output voltage in response to a signal with an unknown angular velocity input from the outside. The gyroscope 4 is installed above the MHD angular velocity sensor 3 and is coaxially arranged with the MHD angular velocity sensor 3 (the axial direction of the integrated angular velocity sensor 16 is Figure 8 the Z direction in

[0102] ). The gyroscope 4 is configured to output a second output voltage in response to a signal with an unknown angular velocity. The signal fusion circuit 7 is installed above the gyroscope 4 and is electrically connected to the MHD angular velocity sensor 3 and the gyroscope 4. The signal fusion circuit 7 is configured to obtain a fusion signal based on the first output voltage and the second output voltage. Figure 3 and Figure 8 As shown, the end cap 33 and the outer shell 32 of the MHD angular velocity sensor 3 are also fixed by screw connection to ensure the stability of the magnetohydrodynamic structure.

[0103] According to an embodiment of the present invention, in order to reduce the volume of the integrated angular velocity sensor 16, the gyroscope 4 uses a chip-type MEMS gyroscope to complete low-frequency angular velocity measurement. The model of the chip-type MEMS gyroscope is MGZ33X. The chip-type MEMS gyroscope is a 48-pin ceramic package with dimensions of 11×11×1.65 mm. The detection axis of rotation is perpendicular to the chip surface. The counterclockwise rotation along the axis of rotation is the positive direction, and the clockwise rotation along the axis of rotation is the negative direction. After the chip-type MEMS gyroscope is soldered to the package circuit board 5, it is fixed above the cylinder 2 through the conductive post 9. The material of the conductive post 9 can be copper. One side of the signal fusion circuit 7 is fixed above the chip-type MEMS gyroscope through the conductive post 9, and the other side of the signal fusion circuit 7 is fixed below the top of the housing 1 through the conductive post 9 and screw connection to ensure that the sensitive axes of the MHD angular velocity sensor 3, the sensitive axis of the chip-type MEMS gyroscope, and the center line of the integrated angular velocity sensor 16 are collinear.

[0104] According to an embodiment of the present invention, holes are provided on the cylinder body 2 for installing connectors 10. The MHD angular velocity sensor 3 is electrically connected to the connectors 10 on the cylinder body 2 through a wire 8, and the connectors 10 on the cylinder body 2 are electrically connected to the signal fusion circuit 7 through a wire 8, so as to facilitate signal transmission between the MHD angular velocity sensor 3 and the signal fusion circuit 7. The chip-type MEMS gyroscope is electrically connected to the signal fusion circuit 7 through a wire 8, so as to facilitate signal transmission between the chip-type MEMS gyroscope and the signal fusion circuit 7. The signal fusion circuit 7 is electrically connected to the connectors 10 on the housing 1 through a wire 8, so as to output a fusion signal. The connector 10 can also be led out as a power supply interface for the integrated angular velocity sensor 16.

[0105] According to an embodiment of the present invention, the signal fusion circuit 7 includes a signal acquisition unit and a processor. The signal acquisition unit is electrically connected to the MHD angular velocity sensor 3 and the gyroscope 4, and the signal acquisition unit is configured to acquire a first output voltage and a second output voltage. The processor includes a first signal processing unit, a second signal processing unit, a third signal processing unit, and a signal output unit. The first signal processing unit is electrically connected to the signal acquisition unit, and the first signal processing unit is configured to respectively output a first angular velocity signal of the MHD angular velocity sensor 3 and a second angular velocity signal of the gyroscope 4 based on the first output voltage and the second output voltage. The second signal processing unit is electrically connected to the first signal processing unit, and the second signal processing unit is configured to superimpose the first angular velocity signal and the second angular velocity signal to obtain a superimposed angular velocity signal, and input the superimposed angular velocity signal into a plurality of candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters. The third signal processing unit is electrically connected to the second signal processing unit, and the third signal processing unit is configured to compare the plurality of gains with each other by using a comparator, and determine the candidate band-pass filter corresponding to the largest gain among the plurality of gains as the target band-pass filter. The signal output unit is electrically connected to the third signal processing unit, and the signal output unit is configured to process the superimposed angular velocity signal by using the target band-pass filter, and select a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located based on the frequency band where the filtered superimposed angular velocity signal is located for fusion to obtain a fusion signal.

[0106] Figure 9 It is a block diagram of a signal fusion circuit according to an embodiment of the present invention.

[0107] According to an embodiment of the present invention, as Figure 9 shown, the signal acquisition unit uses two analog-to-digital conversion chips ADS1256 to implement the analog signal (first output voltage U MHD ) of the MHD angular velocity sensor 3 and the analog signal (second output voltage U MEMSThe acquisition of ) is sent through SPI communication. The processor is implemented based on the FPGA chip EP4CE40F23C8N and receives the first output voltage U sent by two ADS1256s respectively through two-way SPI communication MHD and the second output voltage U MEMS . Multiple frequency bands adaptively select appropriate fusion algorithms to fuse the signals and send the fused signals through SPI communication. The signal output unit in the processor uses the digital-to-analog conversion chip DAC8552 to receive the digital signals sent by the third signal processing unit, and then verifies the fused signals through the experimental test results of the in-band frequency response, noise, and drift in the wide frequency band. Finally, the fused signal Y(s) is converted into an analog signal for output.

[0108] According to an embodiment of the present invention, the integrated angular velocity sensor 16 integrates the MHD angular velocity sensor 3, the gyroscope 4, and the signal fusion circuit 7, reducing the area of the signal transmission loop and avoiding introducing external noise interference. The MHD angular velocity sensor 3 is used to measure high-frequency angular vibration information, and the gyroscope 4 is used to measure low-frequency angular vibration information. The gyroscope 4 is used to complete the low-frequency measurement compensation for the MHD angular velocity sensor 3, realizing wide-band angular velocity measurement from 0.1 Hz to 1 kHz for a single sensor.

[0109] According to an embodiment of the present invention, as Figure 8 shown, the integrated angular velocity sensor 16 further includes a signal detection circuit 6. The signal detection circuit 6 is installed in the cylinder 2 and is located above the angular velocity sensor. The signal detection circuit 6 is configured to amplify the first output voltage output by the angular velocity sensor.

[0110] According to an embodiment of the present invention, the signal detection circuit 6 is connected between the top cover 31 of the MHD angular velocity sensor 3 and the top of the cylinder 2 through a conductive post 9. The MHD angular velocity sensor 3 is electrically connected to the signal detection circuit 6 through a wire 8, and the signal detection circuit 6 is electrically connected to the connector 10 on the cylinder 2 through a wire 8, so that the signal detection circuit 6 can amplify the first output voltage output by the MHD angular velocity sensor 3 and output it to the signal fusion circuit 7.

[0111] Figure 10 is a block diagram of a signal detection circuit according to an embodiment of the present invention.

[0112] According to an embodiment of the present invention, as Figure 10As shown, the signal detection circuit 6 includes a preamplifier circuit 11 and a low-pass filter circuit 12. The preamplifier circuit 11 includes three bipolar transistors SSM-2220 connected in parallel and cascaded with an integrated operational amplifier OP27. The low-pass filter circuit 12 includes a second-order voltage-controlled voltage source low-pass filter circuit built with a low-noise integrated operational amplifier AD797. The signal detection circuit 6 further includes an AC coupling circuit 14 built using an integral feedback structure and a single-ended to differential circuit 13 built using a low-distortion operational amplifier, realizing the function of low-noise amplification and preprocessing of the first output voltage output by the MHD angular velocity sensor 3.

[0113] According to an embodiment of the present invention, as Figure 8 and Figure 9 shown, the signal fusion circuit 7 receives the analog signal output by the MHD angular velocity sensor 3 passing through the signal detection circuit 6 and the analog signal output by the gyroscope 4 through the wire 8, converts them into digital signals using the analog-to-digital conversion module in the signal acquisition unit to complete signal acquisition, and sends them to the processor through SPI communication. The core of the processor is an FPGA. The first signal processing unit in the processor receives the two-way SPI communication data of the signal acquisition unit. The second signal processing unit and the third signal processing unit build a frequency band estimation signal fusion algorithm for signal processing, and send the data to the signal output unit through SPI communication. The signal output unit receives the SPI communication data by a digital-to-analog converter and converts it into a differential signal to complete the output of the fused signal.

[0114] According to an embodiment of the present invention, the integrated angular velocity sensor 16 can form a new generation of micro angular vibration sensitive devices that meet the development needs of space exploration technology, provide data support for aspects such as in-orbit spacecraft structural health monitoring and attitude control, and thus contribute to the innovative development of aerospace science and technology frontiers such as quantum communication, interstellar exploration, and lunar exploration projects.

[0115] Figure 11 is a schematic diagram of a system for measuring angular velocity according to an embodiment of the present invention.

[0116] According to another embodiment of the present invention, as Figure 11As shown, a system for measuring angular velocity is provided. The system for measuring angular velocity includes an isolation table 18, an angular vibration table 17, an integrated angular velocity sensor 16, and a controller 19. The isolation table 18 is fixed on the ground. The angular vibration table 17 is arranged on the isolation table 18 and is configured to generate angular vibration in response to a control signal issued by the controller 19. The integrated angular velocity sensor 16 is arranged on the angular vibration table 17 and is configured to obtain a fusion signal based on the angular vibration by performing the above signal fusion method. The controller 19 is arranged on the ground and is electrically connected to the angular vibration table 17 and the integrated angular velocity sensor 16. The controller 19 is configured to acquire the fusion signal and compare the fusion signal with the angular velocity of the angular vibration generated by the angular vibration table 17, so as to perform error analysis.

[0117] According to an embodiment of the present invention, a platform 20 is arranged on the ground, the controller 19 is placed on the platform 20, and the angular vibration table 17 is arranged on the isolation table 18, which can isolate the ground from the angular vibration table 17 and the integrated angular velocity sensor 16, and reduce the influence of ground vibration on the measurement of the angular velocity of the angular vibration table 17 by the integrated angular velocity sensor 16. The controller 19 controls the angular vibration table 17 arranged on the isolation table 18 to generate angular vibration. The integrated angular velocity sensor 16 arranged on the angular vibration table 17 measures the angular velocity of the angular vibration table 17 in real time by performing the above signal fusion method, obtains a fusion signal, and transmits the fusion signal to the controller 19 through the connector 10 on the housing 1. The controller 19 receives the fusion signal and compares the angular velocity information represented in the fusion signal with the angular velocity of the angular vibration generated by the angular vibration table 17 to verify the consistency of the waveforms, so as to perform error analysis.

[0118] The embodiments of the present invention have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although the embodiments are described separately above, this does not mean that the measures in each embodiment cannot be used advantageously in combination. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, those skilled in the art can make various substitutions and modifications, and these substitutions and modifications should all fall within the scope of the present invention.

Claims

1. A signal fusion method based on an integrated angular velocity sensor, characterized in that, The integrated angular velocity sensor includes an angular velocity sensor based on magnetohydrodynamics, a gyroscope coaxially mounted with the angular velocity sensor, and a signal fusion circuit. The signal fusion circuit is electrically connected to the angular velocity sensor and the gyroscope. A processor is provided on the signal fusion circuit, and a plurality of candidate band-pass filters and comparators are provided in the processor. The signal fusion method is applied to the signal fusion circuit, and the signal fusion method includes: Collecting signals with unknown angular velocity input from the outside by using the angular velocity sensor and the gyroscope to obtain a first output voltage of the angular velocity sensor and a second output voltage of the gyroscope; Inputting the first output voltage and the second output voltage into the processor, and respectively outputting a first angular velocity signal of the angular velocity sensor and a second angular velocity signal of the gyroscope; Superimposing the first angular velocity signal and the second angular velocity signal to obtain a superimposed angular velocity signal; Inputting the superimposed angular velocity signal into a plurality of the candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters; Using the comparator to compare the plurality of gains with each other, and determining the candidate band-pass filter corresponding to the largest gain among the plurality of gains as the target band-pass filter; Processing the superimposed angular velocity signal by using the target band-pass filter, and selecting a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located based on the frequency band of the filtered superimposed angular velocity signal for fusion to obtain a fusion signal.

2. The signal fusion method according to claim 1, wherein The step of inputting the first output voltage and the second output voltage into the processor and respectively outputting the first angular velocity signal of the angular velocity sensor and the second angular velocity signal of the gyroscope includes: Inputting the signal with unknown angular velocity into the processor to determine a first scale factor of the angular velocity sensor and a second scale factor of the gyroscope; Inputting the first output voltage and the first scale factor into the processor to calculate the first angular velocity signal; Inputting the second output voltage and the second scale factor into the processor to calculate the second angular velocity signal.

3. The signal fusion method according to claim 1, wherein The candidate band-pass filters are constructed based on a first cut-off frequency of the angular velocity sensor, a second cut-off frequency of the gyroscope, and an intersection frequency point between the first cut-off frequency and the second cut-off frequency. The intersection frequency point is used as the center frequency of the candidate band-pass filter, and the center frequencies of the plurality of candidate band-pass filters are different from each other.

4. The signal fusion method according to claim 3, characterized in that, The step of inputting the superimposed angular velocity signal into a plurality of the candidate band-pass filters to respectively obtain gains corresponding to the plurality of candidate band-pass filters includes: Inputting the superimposed angular velocity signal into a plurality of the candidate band-pass filters, and calculating root mean square values through a plurality of sliding windows corresponding to the plurality of candidate band-pass filters respectively to obtain gains corresponding to the plurality of candidate band-pass filters.

5. The signal fusion method according to claim 4, wherein Processing the superimposed angular velocity signal by using the target band-pass filter, and based on the frequency band where the filtered superimposed angular velocity signal is located, selecting a fusion algorithm matching the frequency band where the superimposed angular velocity signal is located for fusion to obtain a fusion signal, including: When the filtered superimposed angular velocity signal is within the frequency band of 0.1 Hz to 1 Hz, selecting Kalman filter for fusion to obtain the fusion signal; When the filtered superimposed angular velocity signal is within the frequency band of 1 Hz to 20 Hz, selecting adaptive Kalman filter for fusion to obtain the fusion signal; When the filtered superimposed angular velocity signal is within the frequency band of 20 Hz to 1000 Hz, selecting complementary filter for fusion to obtain the fusion signal.

6. The signal fusion method according to claim 1, wherein The transfer functions of the angular velocity sensor and the gyroscope are constructed through the following steps: Testing multiple scale factors and multiple phase information of the angular velocity sensor and the gyroscope under different frequencies respectively; Using a model fitting function, based on the multiple scale factors and multiple phase information of the angular velocity sensor and the multiple scale factors and multiple phase information of the gyroscope, obtaining the transfer functions of the angular velocity sensor and the gyroscope respectively.

7. An integrated angular velocity sensor, characterized in that, For implementing the signal fusion method based on an integrated angular velocity sensor according to any one of claims 1 to 6, the integrated angular velocity sensor includes: A housing; A cylinder installed in the housing; An angular velocity sensor based on magnetohydrodynamics, installed in the cylinder, the angular velocity sensor being configured to output a first output voltage in response to a signal with an unknown angular velocity input from the outside; A gyroscope, installed above the angular velocity sensor and coaxially arranged with the angular velocity sensor, the gyroscope being configured to output a second output voltage in response to the signal with the unknown angular velocity; A signal fusion circuit, installed above the gyroscope and electrically connected to the angular velocity sensor and the gyroscope, the signal fusion circuit being configured to obtain a fusion signal based on the first output voltage and the second output voltage.

8. The integrated angular velocity sensor according to claim 7, characterized in that, The signal fusion circuit includes: A signal acquisition unit, electrically connected to the angular velocity sensor and the gyroscope, the signal acquisition unit being configured to acquire the first output voltage and the second output voltage; A processor, including: A first signal processing unit, electrically connected to the signal acquisition unit, the first signal processing unit being configured to output a first angular velocity signal of the angular velocity sensor and a second angular velocity signal of the gyroscope respectively based on the first output voltage and the second output voltage; A second signal processing unit, electrically connected to the first signal processing unit, the second signal processing unit being configured to superimpose the first angular velocity signal and the second angular velocity signal to obtain a superimposed angular velocity signal, and input the superimposed angular velocity signal into multiple candidate band-pass filters to obtain gains corresponding to the multiple candidate band-pass filters respectively; A third signal processing unit, electrically connected to the second signal processing unit, configured to compare multiple gains with each other by using a comparator, and determine the candidate band-pass filter corresponding to the largest gain among the multiple gains as the target band-pass filter; A signal output unit, electrically connected to the third signal processing unit, configured to process the superimposed angular velocity signal by using the target band-pass filter, and select a fusion algorithm matching the frequency band where the filtered superimposed angular velocity signal is located for fusion to obtain a fusion signal.

9. The integrated angular velocity sensor according to claim 7, characterized in that, Further comprising: A signal detection circuit, installed inside the cylinder and above the angular velocity sensor, configured to amplify the first output voltage output by the angular velocity sensor.

10. A system for measuring angular velocity, characterized in that, Comprising: A vibration isolation table, fixed to the ground; An angular vibration table, arranged on the vibration isolation table, configured to generate angular vibration in response to a control signal issued by a controller; An integrated angular velocity sensor, arranged on the angular vibration table, configured to obtain a fusion signal by executing the signal fusion method according to any one of claims 1 to 6 based on the angular vibration; A controller, arranged on the ground and electrically connected to the angular vibration table and the integrated angular velocity sensor, configured to acquire the fusion signal and compare the fusion signal with the angular velocity of the angular vibration generated by the angular vibration table, so as to perform error analysis.

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