Debugging method and device of MEMS inertial sensor, terminal and medium

Abstract

The invention provides a debugging method and device of an MEMS inertial sensor, a terminal and a medium, and relates to the technical field of MEMS inertial sensors. According to the invention, the MEMS inertial sensing chip and the vibration sensing chip which are relatively fixed in position are arranged, and the vibration sensing chip is used for collecting the vibration frequency of the inertial sensing chip after vibration damping actually borne by the inertial sensing chip; the vibration frequency after vibration reduction actually measured by the vibration sensing chip is compared with the target working frequency of the inertial sensing chip, so that the compression degree of the vibration reduction module is adjusted, and the vibration frequency after vibration reduction is changed until the vibration frequency after vibration reduction actually borne by the inertial sensing chip under the actual operation working condition is matched with the working frequency of the inertial sensing chip. Therefore, the actual vibration frequency of the inertial sensor after vibration reduction is shifted to the working frequency band, the working frequency band of the MEMS inertial sensor is matched with the actual application frequency band, the inertial sensor chip keeps a large signal-to-noise ratio and small distortion in the actual working environment, and the optimal working performance is played.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of MEMS inertial sensor, and particularly relates to a debugging method and device of MEMS inertial sensor, a terminal and a medium. BACKGROUND

[0002] The MEMS inertial sensor is a MEMS device for detecting linear motion or angular motion of an object by using mass inertia, and can directly output acceleration or angular velocity signals. The working bandwidth of the MEMS inertial sensor is a frequency range in which the sensor can effectively measure, and within the range, the motion of the object can be accurately responded. When the frequency exceeds the range, the output amplitude is reduced, the phase is distorted, and the signal-to-noise ratio is suddenly reduced, and no longer represents the real motion. Before being shipped, the MEMS inertial sensor is usually calibrated by simulating a motion mode to match the motion mode required by a user, so as to operate in an optimal working frequency band.

[0003] However, when the user is not sure about the accurate working frequency band requirement or the actual working frequency band requirement changes, the problem of mismatching of the working frequency band is likely to occur. In addition, in order to resist vibration, a damping pad is usually arranged between the shell and the chip of the inertial sensor. The damping pad changes the vibration frequency while resisting vibration, so that the actual vibration frequency borne by the chip when the external vibration is conducted to the chip position through the shell and the damping pad is not equal to the external vibration frequency. After being shipped, the installation and debugging stage also lacks a calibration environment of simulating a motion mode. Therefore, the existing method usually sets a wide working bandwidth of the MEMS inertial sensor to avoid the problem of mismatching of the working frequency band in actual application. For example, a combination structure sensor of a high-frequency chip and a low-frequency chip is set. For another example, a high-frequency response structure and a low-frequency response structure are arranged in the same chip. The existing method has a complex structure and high cost. SUMMARY

[0004] The embodiments of the present application provide a debugging method, device, terminal and medium of a MEMS inertial sensor to solve the problem of mismatching of the working frequency band of the MEMS inertial sensor and the actual application frequency band.

[0005] In a first aspect, an embodiment of the present application provides a debugging method of a MEMS inertial sensor, the MEMS inertial sensor comprising a MEMS inertial sensing chip, a vibration sensing chip and a damping module; the method comprising: obtaining a working frequency range of the MEMS inertial sensing chip; obtaining a post-damping vibration frequency range; the post-damping vibration frequency range is a frequency range measured by the vibration sensing chip under an actual running condition of a measured object; the MEMS inertial sensor is fixed on the measured object; a relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed; if the working frequency range and the post-damping vibration frequency range are not matched, adjusting a compression degree of the damping module until the working frequency range of the MEMS inertial sensing chip and the post-damping vibration frequency range are matched.

[0006] In a possible implementation, after the post-damping vibration frequency range is obtained, the method further comprises: if the post-damping vibration frequency bandwidth is smaller than the working frequency bandwidth, and a proportion of the post-damping vibration frequency range falling within the working frequency range is not less than a first preset threshold, determining that the working frequency range and the post-damping vibration frequency range are matched; if the post-damping vibration frequency bandwidth is smaller than the working frequency bandwidth, and the proportion of the post-damping vibration frequency range falling within the working frequency range is less than the first preset threshold, determining that the working frequency range and the post-damping vibration frequency range are not matched.

[0007] In a possible implementation, after the post-damping vibration frequency range is obtained, the method further comprises: if the post-damping vibration frequency bandwidth is not smaller than the working frequency bandwidth, a proportion of the working frequency range falling within the post-damping vibration frequency range is not less than a second preset threshold, and a center frequency of the post-damping vibration frequency range also falls within the working frequency range, determining that the working frequency range and the post-damping vibration frequency range are matched; if the post-damping vibration frequency bandwidth is not smaller than the working frequency bandwidth, the proportion of the working frequency range falling within the post-damping vibration frequency range is less than the second preset threshold, or the center frequency of the post-damping vibration frequency range does not fall within the working frequency range, determining that the working frequency range and the post-damping vibration frequency range are not matched.

[0008] In a possible implementation, the obtaining of the post-damping vibration frequency range comprises: obtaining a time domain signal collected by the vibration sensing chip under a working state of the measured object; the time domain signal comprising time and amplitude; converting the time domain signal to obtain a frequency domain signal; the frequency domain signal comprising frequency and amplitude; removing frequencies higher than a preset high frequency in the frequency domain signal to obtain a de-noised frequency domain signal; screening frequencies with amplitudes greater than a threshold in the de-noised frequency domain signal to obtain an amplitude-screened frequency domain signal; and obtaining the post-damping vibration frequency range based on a frequency range of the amplitude-screened frequency domain signal.

[0009] In a possible implementation, the MEMS inertial sensor is a three-axis inertial sensor; the MEMS inertial sensing chip and the vibration sensing chip are arranged in each axis direction with a fixed relative position; and the compression degrees of the damping pads in each axis direction are adjusted independently.

[0010] In a possible implementation, the triaxial inertial sensor is a hexahedron package; for any axial direction, among two faces perpendicular to the axial direction, one face is provided with the MEMS inertial sensing chip, and the other face is provided with the vibration sensing chip.

[0011] In a possible implementation, the MEMS inertial sensor further includes a shell; the damping module is arranged between the shell and the MEMS inertial sensing chip, and arranged between the shell and the vibration sensing chip.

[0012] In a second aspect, an embodiment of the present application provides a debugging device of a MEMS inertial sensor, the MEMS inertial sensor including a MEMS inertial sensing chip, a vibration sensing chip, and a damping module; the device includes: a working frequency acquisition module, configured to acquire a working frequency range of the MEMS inertial sensing chip; a vibration frequency acquisition module, configured to acquire a post-damping vibration frequency range; the post-damping vibration frequency range is a frequency range measured by the vibration sensing chip under an actual running condition of a measured object; the MEMS inertial sensor is fixed on the measured object; a relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed; and an adjustment module, configured to, if the working frequency range and the post-damping vibration frequency range do not match, adjust a compression degree of the damping module until the working frequency range of the MEMS inertial sensing chip and the post-damping vibration frequency range match.

[0013] In a third aspect, an embodiment of the present application provides a terminal, including a memory and a processor, the memory storing a computer program, and the processor implementing the method in the first aspect or any possible implementation manner of the first aspect when executing the computer program.

[0014] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, the computer readable storage medium storing a computer program, and the computer program implementing the method in the first aspect or any possible implementation manner of the first aspect when executed by a processor.

[0015] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, and the computer program implementing the method in the first aspect or any possible implementation manner of the first aspect when executed by a processor.

[0016] The embodiment of the present application sets the position-fixed MEMS inertial sensing chip and the vibration sensing chip, both of which move synchronously, so that the vibration sensing chip collects the actual damping vibration frequency of the inertial sensing chip; under the actual running condition after installation, the actual damping vibration frequency measured by the vibration sensing chip is compared with the target working frequency of the inertial sensing chip, so as to adjust the compression degree of the damping module and change the damping vibration frequency until the actual damping vibration frequency of the inertial sensing chip under the actual running condition matches the working frequency, thereby moving the actual vibration frequency of the inertial sensor after damping into the working frequency band, matching the working frequency band of the MEMS inertial sensor with the actual application frequency band, keeping the inertial sensing chip in the actual working environment with a large signal-to-noise ratio and small distortion, and exerting the best working performance. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is the application scenario diagram of the debugging method of the MEMS inertial sensor provided by the embodiment of the present application; Figure 2 is the implementation flowchart of the debugging method of the MEMS inertial sensor provided by the embodiment of the present application; Figure 3 is the structural schematic diagram of the MEMS inertial sensor provided by the embodiment of the present application; Figure 4 is the structural schematic diagram of the debugging device of the MEMS inertial sensor provided by the embodiment of the present application; Figure 5 is the schematic diagram of the terminal provided by the embodiment of the present application. DETAILED DESCRIPTION

[0018] The embodiment of the present application will be described in detail below with reference to the accompanying drawings.

[0019] Figure 1 is the application scenario diagram of the debugging method of the MEMS inertial sensor provided by the embodiment of the present application. As shown in Figure 1 indicated, the inertial sensor has been widely applied in various fields such as sports health, automobile and flight. The inertial sensor moves synchronously with the moving object to collect inertial data such as acceleration or angular velocity.

[0020] Inertial sensors are not responsive to all vibration frequencies, but only in a certain frequency range, which is the working bandwidth. For example, the core of the inertial sensor is to perceive the external motion / vibration through the inertial displacement of the movable component cantilever beam. For example, when the sensor is subjected to acceleration or external vibration, the mass block fixed at the end of the cantilever beam will produce displacement relative to the cantilever beam base due to inertia, and the sensor will convert this small displacement into an electrical signal through capacitance or other means, and finally calculate the acceleration, vibration amplitude and other parameters. When the external vibration frequency and the working frequency of the cantilever beam are different, the vibration amplitude of the cantilever beam will be greatly different, which directly determines whether the sensor can accurately perceive, which is the physical root of the working bandwidth. The working bandwidth of the inertial sensor is not artificially specified, but is determined by the physical law of the response of the cantilever beam working frequency to the external frequency. Beyond the working bandwidth, the signal is distorted or invalid.

[0021] The first case: when the user purchases, if the user cannot clearly describe the motion mode, but the actual frequency band during actual use may be lower than the calibrated working frequency band; or the actual frequency band is higher than the calibrated frequency band, the working frequency of the cantilever beam of the sensor is much lower than the actual frequency band, and high-frequency vibration cannot produce effective displacement of the cantilever beam, and finally invalid signals are output.

[0022] The second case: the user's demand changes dynamically, and the original calibrated frequency band cannot cover the new scene. Even if the initial demand is clear, if the working frequency band changes during actual use, for example, the sensor is originally used for unmanned aerial vehicle cruising frequency band 10-50Hz, and then changed to unmanned aerial vehicle hovering obstacle avoidance frequency band 0.5-5Hz, mismatching will also occur.

[0023] The embodiment of the present application solves the problem of mismatching between the working frequency band of the MEMS inertial sensor and the actual application frequency band by debugging the sensor structure composed of the MEMS inertial sensing chip and the vibration sensing chip in the actual working environment after installation.

[0024] Figure 2 It is an implementation flowchart of the debugging method of the MEMS inertial sensor provided by the embodiment of the present application. Referring to Figure 2 The debugging method provided by the embodiment of the present application is based on the combined sensor of the inertial sensing chip and the vibration sensing chip. Referring to Figure 1 The MEMS inertial sensor is fixed on the measured object.

[0025] In some embodiments, the MEMS inertial sensor includes a MEMS inertial sensing chip, a vibration sensing chip, and a vibration reduction module.

[0026] It should be noted that in the MEMS inertial sensor, the damping module is used to protect the internal MEMS inertial sensing chip and the vibration sensing chip. The damping module can avoid damage to the structure of the MEMS inertial sensing chip and the vibration sensing chip caused by strong impact. It should also be noted that the compression degree of the damping module is adjustable, that is, the compression degree of the damping module can be adjusted again during the installation and debugging stage after the MEMS inertial sensor is shipped.

[0027] In some embodiments, the MEMS inertial sensor further comprises a shell; the damping module is arranged between the shell and the MEMS inertial sensing chip, and arranged between the shell and the vibration sensing chip.

[0028] Figure 3 is a structural schematic diagram of the MEMS inertial sensor provided by the embodiment of the application; refer to Figure 3 , for example, the MEMS inertial sensor comprises a shell 11, a damping pad 12, and a position-fixed MEMS inertial sensing chip 13 and a vibration sensing chip 14.

[0029] For example, the MEMS inertial sensor can further comprise a rigid carrier. The rigid carrier is fixed with the MEMS inertial sensing chip and the vibration sensing chip. The damping pad is arranged between the rigid carrier and the shell.

[0030] It should also be noted that the compression degree of the damping pad is adjustable. That is, the compression degree of the damping pad can be adjusted during the actual application installation and debugging after shipment. For example, the bolt compression structure, the bolt directly compresses a damping pad, and the compression amount can be adjusted by the bolt. Clockwise screwing the bolt, the bolt presses the damping pad downward, and the compression amount of the damping pad increases; counterclockwise screwing the bolt, the bolt loosens upward, and the compression amount of the damping pad decreases. For another example, the C-shaped damping pad surrounds the rigid carrier, and the cover plate of the shell compresses the C-shaped damping pad and fixes the rigid carrier. Further, the compression degree of the damping pad can be adjusted by adjusting the compression degree of the cover plate.

[0031] It should be further noted that the execution subject of the adjustment action can be an operator or an electric adjustment device. The following adjustment method is used to determine how to adjust. The execution subject of the adjustment method can be a sensor debugging device, and a control module is arranged in the device to execute a program representing the adjustment method. The control module can issue a prompt to guide the operator to specifically adjust the compression degree of the damping pad, or directly control the electric adjustment device to execute the adjustment of the compression degree of the damping pad.

[0032] The above describes the structure of the MEMS inertial sensor, which is the basis of the debugging method. The specific steps of the debugging method of the MEMS inertial sensor are described below. The method comprises: Step 201, obtaining the working frequency range of the MEMS inertial sensing chip.

[0033] The working frequency range, or working vibration frequency range, or working bandwidth, not only represents the width of the working frequency, but also represents the range of the working frequency. The working bandwidth of the MEMS inertial sensing chip is a hardware structure inherent characteristic, and is not a variable that can be arbitrarily adjusted by the user. It can be directly obtained based on the product information provided by the manufacturer.

[0034] Step 202, obtaining the vibration frequency range after damping; the vibration frequency range after damping is a frequency range measured by the vibration sensing chip under the actual running condition of the measured object; the MEMS inertial sensor is fixed on the measured object; the relative position between the vibration sensing chip and the MEMS inertial sensing chip is fixed.

[0035] For example, under the working state of the measured object, the vibration frequency range after damping is obtained through the vibration sensing chip.

[0036] The working frequency range of the vibration sensing chip is usually much larger than that of the MEMS inertial sensing chip. The MEMS inertial sensing chip aims to measure inertial quantities with high precision, and its structure design needs to prioritize low noise and high linearity, which inevitably sacrifices the frequency coverage range. For example, the typical structure of the MEMS inertial sensing chip is a cantilever beam combined with a large mass block. The vibration sensing chip aims to capture full-band vibration signals, and its structure design focuses on wide frequency response capability, with relatively relaxed requirements for local precision. For example, taking a piezoelectric vibration sensing chip as an example, the movable structure is a piezoelectric ceramic piece combined with a small mass block, and the piezoelectric ceramic has extremely large stiffness, much higher than the MEMS silicon cantilever beam, and the mass block is extremely small. Further, the structure of the vibration sensing chip is usually simple, and the manufacturing cost is also much lower than that of the MEMS inertial sensing chip. In summary, the embodiment of the present application determines the vibration frequency after damping in a larger frequency range through the vibration sensing chip with lower cost and wider bandwidth.

[0037] It should be noted that the actual running condition of the measured object is the actual working state of the user using the MEMS inertial sensor. For example, in the field of vehicle applications, after installing the MEMS inertial sensor on the vehicle, the actual driving process of the vehicle is the working state.

[0038] Whether it is vehicle driving, equipment operation, human activity, or environmental interference, the essence of its movement is periodic vibration. The main factor affecting MEMS inertial sensors is frequency. Users may not be able to predict the real use frequency, which is rooted in the complexity of the real use scenario far exceeding the prediction. For example, the use frequency of the same measured object will change with the working condition, rather than a fixed value; for another example, the vibration of the measured object not only contains its own working vibration, but also superimposes environmental interference vibration, and the interference frequency is often unknown. Further, assuming that the user determines the vibration frequency of the measured object itself through preliminary testing, but this frequency is the original frequency before vibration reduction, and the frequency after vibration reduction transmitted to the sensor chip will change unpredictably due to the nonlinear characteristics of the vibration reduction pad, installation errors and other factors, which cannot be directly derived by theoretical calculation.

[0039] The embodiment of the present application adopts real-time acquisition, and directly acquires the vibration signal at the installation position of the MEMS inertial sensing chip inside the sensor. At this time, the frequency after vibration reduction obtained is the frequency directly interacting with the MEMS inertial sensing chip. Therefore, the problems that the user cannot determine the use frequency and cannot accurately derive the frequency after vibration reduction are solved, and the frequency data obtained is real and relevant.

[0040] In some embodiments, the MEMS inertial sensor is fixed on the measured object; and the relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed.

[0041] It should be noted that the fact that the MEMS inertial sensor is fixed on the measured object means that the vibration of the measured object is transmitted to the MEMS inertial sensor. The fact that the relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed means that the vibration sensing chip and the MEMS inertial sensing chip move synchronously. The vibration measured by the vibration sensing chip is the frequency after vibration reduction.

[0042] In a real scene, the signal collected by the vibration sensing chip is a mixed signal of effective vibration and various noises. For example, the target vibration signal of the motor after vibration reduction may be mixed with ground low-frequency interference and circuit high-frequency noise. Directly using the original signal cannot distinguish which frequency is the vibration after vibration reduction that needs to be concerned and which is irrelevant noise. Therefore, the embodiment of the present application processes through steps 2021-2025 to strip noise and focus on effective frequency, and finally obtains the accurate frequency range of vibration after vibration reduction.

[0043] In a possible implementation manner, the frequency range of vibration after vibration reduction is obtained, including: Step 2021, acquiring a time domain signal collected by the vibration sensing chip under the working state of the measured object; the time domain signal includes time and amplitude; The time-domain signal is represented by time as the horizontal axis and vibration amplitude as the vertical axis, and represents the law of vibration amplitude changing with time. The vibration sensing chip, such as a piezoelectric type, continuously captures the vibration of the measured object at a fixed sampling rate. Each sampling records two key data: sampling time and vibration amplitude at that time, and finally forms the original data corresponding to time and amplitude, i.e. the time-domain signal. Here, all the information of the vibration and noise after damping in the real scene is completely retained, whether it is the low-frequency vibration needed or the high-frequency noise irrelevant, which will be recorded in the form of amplitude changing with time.

[0044] Step 2022, converting the time-domain signal to obtain a frequency-domain signal; the frequency-domain signal includes frequency and amplitude; The time-domain signal can only see the fluctuation of amplitude with time, but cannot directly know which frequency components are contained in the fluctuation. Fourier transform, such as fast Fourier transform, can convert the time-domain signal into a frequency-domain signal containing frequency and amplitude. The frequency-domain signal represents the intensity of vibration of different frequencies in the overall vibration. This step separates the mixed vibration into individual frequency components, and can clearly see which frequencies exist and how strong the vibration of each frequency is, laying a foundation for subsequent screening of effective frequencies.

[0045] Step 2023, removing frequencies higher than a preset high frequency in the frequency-domain signal to obtain a denoised frequency-domain signal; The preset high frequency is a noise cutoff frequency set based on the performance of the vibration sensing chip and the actual scene requirements. For example, if the measured object is an industrial motor, its normal vibration frequency after damping is usually not more than 500 Hz, and signals above 1000 Hz are mostly circuit thermal noise or environmental electromagnetic interference. These high-frequency signals are meaningless for judging whether the MEMS inertial sensor is suitable, and are irrelevant noise. Therefore, by using a signal processing algorithm such as a low-pass filter, the frequency components in the frequency-domain signal higher than the preset high frequency can be filtered out. This step first eliminates obvious irrelevant high-frequency noise to reduce interference in subsequent screening.

[0046] Step 2024, screening frequencies with amplitudes greater than a threshold value in the denoised frequency-domain signal to obtain an amplitude-screened frequency-domain signal; The amplitude threshold is a minimum value set based on the effective intensity of vibration. For example, if the vibration amplitude is too small, its effect on the MEMS inertial sensor is negligible, and the sensor cannot distinguish between vibration and noise. Such small-amplitude vibration can be considered as invalid signal; on the contrary, when the amplitude is large, it is the effective vibration that can actually affect the sensor. This step further screens the effective frequencies that have actual impact from the denoised frequencies, avoiding counting weak invalid vibrations into the frequency range after damping, and ensuring that the final frequency range is the frequency range that the MEMS inertial sensor really needs to adapt to.

[0047] At step 2025, a frequency range of the vibration after damping is obtained based on the amplitude screening of the frequency domain signal.

[0048] For example, the frequency range of the vibration after damping refers to an interval from a minimum value to a maximum value of all effective frequencies in the frequency domain signal after the amplitude screening. For example, if the effective frequencies after the screening are 50 Hz (0.3 g), 80 Hz (0.25 g), and 100 Hz (0.2 g), the minimum frequency is 50 Hz, the maximum frequency is 100 Hz, and the frequency range of the vibration after damping is finally determined as 50 Hz-100 Hz.

[0049] If there are multiple discrete effective frequencies, even if there is a missing frequency in the middle, the span of all effective frequencies needs to be covered to ensure that the MEMS sensor bandwidth can cover all effective frequencies. The discrete effective frequencies are converted into a continuous frequency interval. Subsequently, it needs to be determined whether the working bandwidth of the MEMS inertial sensor covers the interval and whether the damping module needs to be adjusted.

[0050] The above embodiment gives a way to determine the effective frequency range of the vibration after damping.

[0051] In a possible implementation, after obtaining the frequency range of the vibration after damping, the method further includes determining whether the working frequency range and the frequency range of the vibration after damping match.

[0052] The matching is not that the sensor bandwidth and the frequency after damping are completely consistent, but that the working frequency range of the sensor can cover the effective vibration frequency after damping, or the covered frequencies are all in the optimal performance interval of the sensor. On the one hand, the minimum value of the frequency range of the vibration after damping is greater than or equal to the lower limit of the working bandwidth of the sensor, and the maximum value of the frequency after damping is less than or equal to the upper limit of the working bandwidth of the sensor, so as to ensure that all effective vibration frequencies are within the response capability range of the sensor, and to ensure that low-frequency capture or high-frequency attenuation distortion does not occur. On the other hand, the effective vibration frequency after damping does not fall into the performance invalidation interval of the sensor, mainly the resonance section, that is, the interval close to the inherent frequency of the movable structure of the sensor, to avoid signal serious distortion or sensor damage caused by resonance.

[0053] The mismatch can include partial mismatch and complete mismatch. The complete matching means that the frequency range of the vibration after damping is 100% within the effective interval of the working bandwidth of the sensor. The effective interval needs to exclude the performance invalidation section, such as the resonance section. For example, the vibration frequency is overall beyond one end of the working frequency range, or part of it does not fall into the working frequency range. The mismatch can also include high and low. The high and low are based on the overall position relationship between the frequency range of the vibration and the working frequency range.

[0054] The following embodiment illustrates the case that the vibration frequency bandwidth after damping is less than the working frequency bandwidth. When the vibration bandwidth < sensor bandwidth, the sensor is theoretically capable of covering all the vibration, thereby further confirming whether the vibration is really within the sensor bandwidth or only partially falls within.

[0055] In a possible implementation, after the vibration frequency range after damping is acquired, the method further includes: Step A1, if the vibration frequency bandwidth after damping is less than the working frequency bandwidth, and the proportion of the vibration frequency range after damping falling within the working frequency range is not less than a first preset threshold, it is determined as matching. For example, the falling proportion is the ratio of the length of the frequency falling within the sensor working bandwidth in the vibration frequency range to the total bandwidth of the vibration. When the vibration bandwidth is less than the sensor bandwidth, if most or even all of the vibration frequencies fall within the sensor bandwidth, it indicates that the sensor can completely cover the effective frequency range of the vibration and no key frequency is missing.

[0056] The first preset threshold is a quantitative standard for determining whether to match, and its value needs to be combined with the accuracy requirement of the application scenario. For example, the first preset threshold can be 100%. The first preset threshold being 100% is the most stringent matching standard, which is suitable for scenarios with extremely high requirements for frequency coverage completeness.

[0057] Step A2, if the vibration frequency bandwidth after damping is less than the working frequency bandwidth, and the proportion of the vibration frequency range after damping falling within the working frequency range is less than the first preset threshold, it is determined as not matching.

[0058] When most of the frequencies of the vibration do not fall within the sensor bandwidth, even if the vibration bandwidth is narrower, the sensor cannot capture the core vibration signal, resulting in invalid data.

[0059] The embodiment of the application measures the overlapping degree of the vibration and the sensor by the falling proportion when the vibration bandwidth is less than the sensor bandwidth. The higher the proportion, the better the matching degree.

[0060] The following embodiment illustrates the case that the vibration frequency bandwidth after damping is not less than the working frequency bandwidth. If the vibration bandwidth ≥ sensor bandwidth, the sensor bandwidth cannot completely cover the vibration, and thus it needs to be concerned whether the sensor can cover the important central frequency of the vibration and whether the vibration range covered by the sensor is large enough. Only when both conditions are met, can it be ensured that the signal collected by the sensor has practical significance, rather than only capturing the edge invalid frequency of the vibration.

[0061] In a possible implementation, after the vibration frequency range after damping is acquired, the method further includes: Step B1, if the vibration frequency bandwidth after damping is not less than the working frequency bandwidth, the proportion of the working frequency range falling into the vibration frequency range after damping is not less than the second preset threshold, and the center frequency of the vibration frequency range after damping also falls into the working frequency range, it is determined as matching; The proportion of the working frequency range falling into the vibration range is the proportion of the width of the overlapping part of the sensor bandwidth and the vibration range to the sensor bandwidth. Please note that here is the proportion of the sensor bandwidth overlap, not the proportion of the vibration bandwidth overlap.

[0062] For example, the center frequency can be the midpoint of the vibration frequency range after damping. The center frequency is usually the frequency with the most concentrated vibration energy. If the center frequency falls into the sensor bandwidth, the sensor covers the core interval with the strongest vibration energy, the signal-to-noise ratio of the collected signal is high, and the real state of the vibration can be accurately reflected.

[0063] The second preset threshold is a standard representing the use of the working frequency range of the sensor itself. When the vibration bandwidth is greater than or equal to the sensor bandwidth, the sensor can only cover a part of the vibration at most. If the falling proportion is too low, it means that the use rate of the working frequency range of the sensor itself is small. For example, the second preset threshold can be set to 100%.

[0064] Step B2, if the vibration frequency bandwidth after damping is not less than the working frequency bandwidth, the proportion of the working frequency range falling into the vibration frequency range after damping is less than the second preset threshold, or the center frequency of the vibration frequency range after damping does not fall into the working frequency range, it is determined as not matching.

[0065] For example, if the vibration frequency bandwidth after damping is not less than the working frequency bandwidth, the proportion of the working frequency range falling into the vibration frequency range after damping is less than the second preset threshold, it is determined as not matching; if the vibration frequency bandwidth after damping is not less than the working frequency bandwidth, and the center frequency of the vibration frequency range after damping does not fall into the working frequency range, it is determined as not matching.

[0066] Step 203, if the working frequency range and the vibration frequency range after damping do not match, adjust the compression degree of the damping module until the working frequency range of the MEMS inertial sensor chip and the vibration frequency range after damping match.

[0067] Referring to the above, it has been explained that the compression degree of the damping module is adjustable. The compression degree directly determines the stiffness of the damping module, which further affects the system natural frequency, and the system natural frequency is the core of screening the vibration frequency. When the vibration is transmitted through the damping module, the system natural frequency determines which frequencies can be transmitted and which frequencies will be filtered. Therefore, adjusting the compression degree can change the screening range, and finally realize the adjustment of the vibration frequency range after damping.

[0068] The greater the compression degree is within the elastic limit of the damping module material, the greater the rigidity is, for example, the more the soft rubber is pressed, the harder the rubber is, and the stronger the ability to resist deformation is; on the contrary, the smaller the compression degree is, the smaller the rigidity is. The damping module and the chip constitute a vibration system. According to the vibration transmission law, only the vibration with a frequency close to the natural frequency of the system can be effectively transmitted to the chip position to form the vibration after damping; the vibration with a larger frequency of the vibration source will be greatly filtered by the damping module and cannot form the effective vibration after damping. Therefore, the height of the natural frequency of the system directly determines the upper limit of the frequency range of the vibration after damping. The higher the natural frequency of the system is, the more high-frequency vibrations can be transmitted, and the wider the frequency range after damping is; the lower the natural frequency of the system is, the less high-frequency vibrations can be transmitted, and the narrower the frequency range after damping is.

[0069] In a possible implementation, the method for changing the frequency range of the vibration after damping by adjusting the compression degree of the damping module comprises: increasing the frequency range of the vibration after damping by increasing the compression degree of the damping module; or reducing the frequency range of the vibration after damping by reducing the compression degree of the damping module.

[0070] For example, the compression amount of the damping module is reduced by loosening the bolt, the rigidity is reduced, the natural frequency of the system is reduced, the upper limit of the high-frequency vibration that can be transmitted is reduced, and the frequency range after damping is reduced.

[0071] For example, the compression amount of the damping module is increased by pressing the bolt, the rigidity is increased, the natural frequency of the system is increased, the upper limit of the high-frequency vibration that can be transmitted is increased, and the frequency range after damping is increased.

[0072] The embodiment of the application sets the MEMS inertial sensing chip and the vibration sensing chip with a relatively fixed position, and the two synchronously move, so that the vibration sensing chip collects the frequency of the vibration after damping actually borne by the inertial sensing chip; under the actual running condition after installation, the frequency of the vibration after damping actually measured by the vibration sensing chip is compared with the target working frequency of the inertial sensing chip, so as to adjust the compression degree of the damping module and change the frequency of the vibration after damping, until the frequency of the vibration after damping actually borne by the inertial sensing chip under the actual running condition matches the working frequency, so that the actual vibration frequency of the inertial sensor after damping is moved into the working frequency band, the working frequency band of the MEMS inertial sensor is matched with the application frequency band, the inertial sensing chip keeps a large signal-to-noise ratio and a small distortion in the actual working environment, and the best working performance is achieved.

[0073] In a possible implementation, the MEMS inertial sensor is a three-axis inertial sensor; the MEMS inertial sensing chip and the vibration sensing chip are arranged in each axis direction and have a relatively fixed position; and the compression degree of the damping module in each axis direction is adjusted independently.

[0074] The triaxial MEMS inertial sensor respectively measures inertial signals of three orthogonal axial directions X, Y and Z.

[0075] For example, one vibration sensing chip is configured for each of the three axial directions X, Y and Z, and the sensitive direction of each vibration sensing chip strictly corresponds to the axial direction.

[0076] For example, one MEMS inertial sensing chip is configured for each of the three axial directions X, Y and Z, such as an X-direction accelerometer chip, a Y-direction accelerometer chip and a Z-direction accelerometer chip.

[0077] For example, one vibration damping pad is arranged for each of the three axial directions X, Y and Z, such as one left and one right for the X-direction, one front and one back for the Y-direction, and one up and one down for the Z-direction.

[0078] The embodiment of the present application solves the problem of frequency band mismatch caused by multi-axial vibration coupling, and ensures that the three-axis MEMS inertial sensing chips can work in the best frequency band.

[0079] In a possible implementation, the triaxial inertial sensor is a hexahedral package; for any axial direction, among two faces perpendicular to the same axial direction, one face is provided with a MEMS inertial sensing chip, and the other face is provided with a vibration sensing chip.

[0080] It should be noted that the triaxial inertial sensor is a hexahedral package; for any axial direction, among two faces perpendicular to the same axial direction, one face is provided with a MEMS inertial sensing chip, and the other face is provided with a vibration sensing chip, so that the vibration sensing chip and the MEMS chip face each other, and ensure that they perceive the vibration of the same axial direction and the same position.

[0081] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0082] The following is a device embodiment of the present application, and for details not described in detail, reference can be made to the corresponding method embodiments described above.

[0083] Figure 4A schematic diagram of the debugging device for a MEMS inertial sensor provided in an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below: The MEMS inertial sensor is fixed to the object being measured; the MEMS inertial sensor includes a housing, a vibration damping pad, and a MEMS inertial sensing chip and a vibration sensing chip with relatively fixed positions; a debugging device 4 for a MEMS inertial sensor includes: The acquisition module 41 is used to acquire the operating frequency range of the MEMS inertial sensing chip.

[0084] The vibration frequency acquisition module 42 is used to acquire the vibration frequency range after vibration reduction; the vibration frequency range after vibration reduction is the frequency range measured by the vibration sensing chip under the actual operating conditions of the object under test; the MEMS inertial sensor is fixed on the object under test; the relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed.

[0085] The adjustment module 43 is used to adjust the compression degree of the vibration damping module if the operating frequency range does not match the vibration frequency range after vibration damping, until the operating frequency range of the MEMS inertial sensing chip matches the vibration frequency range after vibration damping.

[0086] This invention employs a MEMS inertial sensor chip and a vibration sensor chip with relatively fixed positions, both moving synchronously. The vibration sensor chip collects the vibration frequency actually experienced by the inertial sensor chip after vibration reduction. Under actual operating conditions after installation, the vibration frequency measured by the vibration sensor chip after vibration reduction is compared with the target operating frequency of the inertial sensor chip. The compression degree of the vibration reduction module is adjusted accordingly, and the vibration frequency after vibration reduction is changed until the vibration frequency actually experienced by the inertial sensor chip under actual operating conditions matches its operating frequency. This shifts the actual vibration frequency of the inertial sensor after vibration reduction into the operating frequency band, ensuring that the operating frequency band of the MEMS inertial sensor matches the actual application frequency band. The inertial sensor chip maintains a high signal-to-noise ratio and low distortion in the actual working environment, achieving optimal performance.

[0087] Figure 5 This is a schematic diagram of a terminal provided in an embodiment of the present invention. Figure 5 As shown, the terminal 5 in this embodiment includes a processor 50 and a memory 51. The memory 51 stores a computer program 52. When the processor 50 executes the computer program 52, it implements the steps in the various method embodiments described above. Alternatively, when the processor 50 executes the computer program 52, it implements the functions of each module / unit in the various device embodiments described above.

[0088] By way of example, the computer program 52 can be segmented into one or more modules / units that are stored in the memory 51 and executed by the processor 50 to accomplish the present application. The one or more modules / units can be a series of computer program instruction segments that accomplish a specific function, and are used to describe the execution process of the computer program 52 in the terminal 5.

[0089] The terminal 5 can include, but is not limited to, the processor 50 and the memory 51. Those skilled in the art can understand that the terminal 5 can include more or fewer components than those shown, or combine certain components, or include different components, such as input / output devices, network access devices, buses, and the like. Figure 5 The terminal 5 is merely an example and does not constitute a limitation on the terminal 5, and can include more or fewer components than those shown, or combine certain components, or include different components, such as input / output devices, network access devices, buses, and the like.

[0090] The processor 50 can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic, discrete hardware components, or the like. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0091] The memory 51 can be an internal storage unit of the terminal 5, such as a hard disk or a memory of the terminal 5. The memory 51 can also be an external storage device of the terminal 5, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, or the like, which is equipped on the terminal 5. Further, the memory 51 can include both an internal storage unit and an external storage device of the terminal 5. The memory 51 is used to store the computer program 52 and other programs and data required by the terminal 5. The memory 51 can also be used to temporarily store data that has been output or will be output.

[0092] For the convenience and brevity of description, only the division of the above functional modules / units is exemplified, and in actual applications, the above functions can be completed by different functional modules / units as needed. The above modules / units can be implemented in the form of hardware, software, or a combination of hardware and software.

[0093] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the method in each method embodiment.

[0094] The embodiment of the present application further provides a computer program product, which comprises a computer program. The computer program is executed by a processor to implement the method in each method embodiment.

[0095] The computer program comprises computer program code, which can be in the form of source code, object code, executable files or some intermediate forms. The computer readable medium can comprise any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, Read-Only Memory (ROM), Random Access Memory (RAM), electric carrier wave signal, telecommunication signal and software distribution medium, etc.

[0096] In the above embodiments, the description of each embodiment has its own focus, and the parts not described or recorded in a certain embodiment can be referred to the relevant description of other embodiments. If there is no special description and no logical conflict, the terms and / or descriptions of different embodiments are consistent and can be mutually referred to, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0097] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for debugging a MEMS inertial sensor, characterized in that, The MEMS inertial sensor includes a MEMS inertial sensing chip, a vibration sensing chip, and a vibration reduction module; the method includes: Obtain the operating frequency range of the MEMS inertial sensor chip; The vibration frequency range after vibration reduction is obtained; the vibration frequency range after vibration reduction is the frequency range measured by the vibration sensing chip under the actual operating conditions of the object under test; the MEMS inertial sensor is fixed on the object under test; the relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed. If the operating frequency range does not match the vibration frequency range after vibration reduction, the compression degree of the vibration reduction module is adjusted until the operating frequency range of the MEMS inertial sensing chip matches the vibration frequency range after vibration reduction.

2. The debugging method for a MEMS inertial sensor according to claim 1, characterized in that, After obtaining the vibration frequency range after vibration reduction, the method further includes: If the vibration frequency bandwidth after vibration reduction is less than the working frequency bandwidth, and the proportion of the vibration frequency range after vibration reduction falling within the working frequency range is not less than the first preset threshold, then it is determined to be a match; If the vibration frequency bandwidth after vibration reduction is less than the working frequency bandwidth, and the proportion of the vibration frequency range after vibration reduction falling within the working frequency range is less than the first preset threshold, then it is determined to be a mismatch.

3. The debugging method for a MEMS inertial sensor according to claim 1, characterized in that, After obtaining the vibration frequency range after vibration reduction, the method further includes: If the vibration frequency bandwidth after vibration reduction is not less than the working frequency bandwidth, the proportion of the working frequency range falling into the vibration frequency range after vibration reduction is not less than the second preset threshold, and the center frequency of the vibration frequency range after vibration reduction also falls into the working frequency range, then it is determined to be a match. If the vibration frequency bandwidth after vibration reduction is not less than the working frequency bandwidth, the proportion of the working frequency range falling within the vibration frequency range after vibration reduction is less than the second preset threshold, or the center frequency of the vibration frequency range after vibration reduction does not fall within the working frequency range, then it is determined to be a mismatch.

4. The debugging method for a MEMS inertial sensor according to claim 1, characterized in that, The range of vibration frequencies obtained after vibration reduction includes: The vibration sensing chip acquires the time-domain signal under the working state of the object being tested; the time-domain signal includes time and amplitude. The time-domain signal is converted to a frequency-domain signal; the frequency-domain signal includes frequency and amplitude. Remove frequencies higher than a preset high frequency from the frequency domain signal to obtain the denoised frequency domain signal; The frequency domain signal with amplitude greater than a threshold is selected from the denoised frequency domain signal to obtain the amplitude-selected frequency domain signal. Based on the frequency range of the frequency domain signal after amplitude filtering, the vibration frequency range after vibration reduction is obtained.

5. The debugging method for a MEMS inertial sensor according to claim 1, characterized in that, The MEMS inertial sensor is a triaxial inertial sensor; each axis is equipped with a MEMS inertial sensing chip and a vibration sensing chip with relatively fixed positions; the compression degree adjustment of each axis vibration reduction module is independent of each other.

6. The debugging method for a MEMS inertial sensor according to claim 5, characterized in that, The triaxial inertial sensor is encapsulated in a hexahedral shape. For any given axis, in two planes perpendicular to the same axis, a MEMS inertial sensor chip is placed on one plane and a vibration sensor chip is placed on the other plane.

7. The debugging method for a MEMS inertial sensor according to claim 1, characterized in that, The MEMS inertial sensor also includes a housing; the vibration damping module is disposed between the housing and the MEMS inertial sensing chip, and also between the housing and the vibration sensing chip.

8. A debugging device for a MEMS inertial sensor, characterized in that, The MEMS inertial sensor includes a MEMS inertial sensing chip, a vibration sensing chip, and a vibration reduction module; the device includes: The operating frequency acquisition module is used to acquire the operating frequency range of the MEMS inertial sensing chip. The vibration frequency acquisition module is used to acquire the vibration frequency range after vibration reduction; the vibration frequency range after vibration reduction is the frequency range measured by the vibration sensing chip under the actual operating conditions of the object under test; the MEMS inertial sensor is fixed on the object under test; the relative position of the vibration sensing chip and the MEMS inertial sensing chip is fixed. An adjustment module is used to adjust the compression degree of the vibration damping module if the operating frequency range does not match the vibration frequency range after vibration damping, until the operating frequency range of the MEMS inertial sensing chip matches the vibration frequency range after vibration damping.

9. A terminal, characterized in that, It includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the debugging method of the MEMS inertial sensor as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the debugging method for the MEMS inertial sensor as described in any one of claims 1 to 7.

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