A method, apparatus, medium, and device for noise processing in an inertial navigation system.

Abstract

This invention discloses a noise processing method, apparatus, medium, and device for inertial navigation systems, relating to the field of inertial navigation system design. The method includes: conducting random vibration tests on the inertial navigation system to obtain test data; performing noise band testing on the test data using low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges; within each initial noise band range, performing noise band testing on the test data using notch filters with different initial frequencies to obtain multiple target noise band ranges; the target noise band ranges are the noise band ranges generated by frequency aliasing; within each target noise band range, designing notch filter parameters for the target noise band range to obtain a target notch filter; and using the target notch filter to filter out the noise signal output by the inertial navigation system. This method can process noise signals generated by frequency aliasing in inertial navigation systems.

Description

Technical Field

[0001] This invention relates to the field of inertial navigation system design, and particularly to a noise processing method, apparatus, medium, and device for inertial navigation systems. Background Technology

[0002] Micro-Electro-Mechanical Systems (MEMS) based inertial navigation systems have attracted increasing attention and are widely used in various fields due to their small size, high reliability, and fully autonomous navigation capabilities. Currently, most MEMS inertial navigation systems are connected to the device under test (DUT) via strapdown connections. However, the rigid connections and the complex mechanical environment during operation result in significant output noise, severely impacting the accuracy of inertial navigation calculations. Therefore, the method of handling external noise in inertial navigation systems has become a key issue affecting the development of inertial navigation.

[0003] Currently, noise reduction methods for inertial navigation systems (INS) typically fall into two categories: First, designing physical damping mechanisms within the existing INS and then potting it before use. However, potting significantly increases the product's operational risks. Alternatively, users can add damping to the contact surfaces between the INS and the equipment, but this external damping greatly increases design costs. Second, adding digital low-pass filters to the INS removes high-frequency noise, allowing it to output a valid signal. While this simple low-pass filtering method effectively processes ultra-high-frequency signals to some extent, it cannot address noise generated by frequency aliasing. Furthermore, when the low-pass filter's cutoff frequency is designed too low, it filters out some valid signals, reducing the accuracy of navigation calculations.

[0004] Therefore, there is an urgent need for a method to process noise signals generated by frequency aliasing in inertial navigation systems. Summary of the Invention

[0005] Therefore, it is necessary to provide a noise processing method, apparatus, medium, and device for inertial navigation systems to address the aforementioned technical problems. This method can process noise signals generated by frequency aliasing effects in inertial navigation systems.

[0006] The present invention adopts the following technical solution:

[0007] This invention provides a noise processing method for an inertial navigation system, comprising:

[0008] Random vibration tests were conducted on the inertial navigation system to obtain random vibration test data;

[0009] Noise band measurements were performed on random vibration test data using low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges.

[0010] For each initial noise frequency band, noise frequency band tests were performed on the random vibration test data using notch filters with different initial frequencies to obtain multiple target noise frequency bands; the target noise frequency bands are the noise frequency bands generated by the frequency aliasing effect.

[0011] For each target noise frequency band, the parameters of the notch filter within the target noise frequency band are designed to obtain the target notch filter; and the target notch filter is used to filter out the noise signal within the target noise frequency band in the output data of the inertial navigation system.

[0012] Preferably, noise band measurements are performed on random vibration test data using low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges, specifically including:

[0013] Obtain the initial cutoff frequency of the low-pass filter and determine the transfer function of the low-pass filter at the initial cutoff frequency;

[0014] Input the random vibration test data into the designed low-pass filter and record the ratio of the time domain signal amplitude of the random vibration test data before and after processing by the low-pass filter.

[0015] The initial cutoff frequency of the low-pass filter is adjusted by a first preset step size increment, and the transfer function of the low-pass filter after the corresponding initial cutoff frequency is determined.

[0016] Input the random vibration test data into the low-pass filter after the initial cutoff frequency update, and record the ratio of the time domain signal amplitude of the random vibration test data before and after processing by the low-pass filter after the initial cutoff frequency update.

[0017] When the output frequency of an inertial navigation system is greater than a preset multiple of the initial cutoff frequency, the ratio of the time-domain signal amplitude under any adjacent initial cutoff frequency setting is compared. If the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial cutoff frequency settings exceeds a first preset threshold, then the frequency range between adjacent initial cutoff frequencies is determined as the initial noise frequency band range.

[0018] Preferably, under each initial noise frequency band, noise frequency band tests are performed on the random vibration test data using notch filters with different initial frequencies to obtain multiple target noise frequency bands, specifically including:

[0019] For any initial noise frequency band, the minimum frequency within the initial noise frequency band is taken as the initial frequency of the notch filter.

[0020] Input the random vibration test data into the notch filter after parameter design, and record the ratio of the time domain signal amplitude of the random vibration test data before and after notch filter processing.

[0021] The initial frequency of the notch filter is adjusted by the second preset step size increment to obtain the frequency-updated notch filter. The random vibration test data is then input into the frequency-updated notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after processing by the frequency-updated notch filter is recorded.

[0022] When the updated initial frequency is the maximum frequency within the initial noise frequency band, compare the time-domain signal amplitude ratio under any adjacent initial frequency setting. If the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial frequency settings exceeds the second preset threshold, then the frequency range between adjacent initial frequencies is determined as the target noise frequency band range.

[0023] Preferably, the notch filter parameters include a first notch parameter and a second notch parameter. For each target noise frequency band, the notch filter parameters are designed for that specific target noise frequency band to obtain the target notch filter. Specifically, this includes:

[0024] For any target noise frequency band, the center of the target noise frequency band is determined as the center frequency of the notch filter, and the first initial value of the first notch parameter and the second initial value of the second notch parameter of the notch filter are obtained.

[0025] With the first initial value unchanged, the second initial value is adjusted by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions. The second initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal is determined as the value of the second notch parameter.

[0026] Keep the value of the second notch parameter, adjust the first initial value with a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determine the first initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the first notch parameter.

[0027] The target notch filter is obtained based on the values ​​of the first notch parameter and the second notch parameter.

[0028] Preferably, the second initial value is adjusted by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, including:

[0029] The second initial value is adjusted by a third preset step size increment. If the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the second initial value, the second initial value is adjusted by a third preset step size decrease until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the second initial value stops.

[0030] Preferably, the first initial value is adjusted by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, including:

[0031] The first initial value is adjusted by a third preset step size increment. If the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the first initial value, the first initial value is adjusted by a third preset step size decrease until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the first initial value stops.

[0032] Preferably, the method further includes:

[0033] After obtaining the target notch filter, random vibration tests were conducted on the inertial navigation system to determine the noise processing performance of the target notch filter. The target notch filter is the noise processing component of the inertial navigation system.

[0034] This invention provides a noise processing device for an inertial navigation system, comprising:

[0035] The acquisition module is used to acquire random vibration test data obtained from random vibration tests on inertial navigation systems.

[0036] The first processing module is used to test the noise frequency band of random vibration test data under low-pass filters with different initial cutoff frequencies, and to determine multiple initial noise frequency band ranges.

[0037] The second processing module is used to perform noise band testing of the random vibration test data with notch filters at different initial frequencies under each initial noise band range, to obtain multiple target noise band ranges; the target noise band range is the noise band range generated by the frequency aliasing effect.

[0038] The third processing module is used to design the notch filter parameters for each target noise frequency band to obtain the target notch filter; and to use the target notch filter to filter out noise signals in the target noise frequency band of the inertial navigation system output data.

[0039] The present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described noise processing method for an inertial navigation system.

[0040] The present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the noise processing method of an inertial navigation system described above.

[0041] The above-mentioned at least one technical solution adopted in this invention can achieve the following beneficial effects:

[0042] This method involves acquiring random vibration test data from an inertial navigation system (INS). Noise band measurements are then performed on the test data using low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges. Based on each initial noise band range, noise band measurements are further performed on the random vibration test data using notch filters with different initial frequencies to obtain multiple target noise band ranges. These target noise band ranges represent the noise band range generated by frequency aliasing. For each target noise band range, notch filter parameters are designed to filter out noise signals generated by aliasing. This technique, by designing multiple low-pass filters and multiple notch filters with different initial cutoff frequencies, can precisely process noise generated by frequency aliasing in the INS, while more completely preserving the effective signal output by the actual INS. Furthermore, this method requires no structural or hardware modifications to the existing INS, making it highly practical in engineering applications. Attached Figure Description

[0043] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0044] Figure 1 A schematic flowchart of a noise processing method for an inertial navigation system provided by the present invention;

[0045] Figure 2 A detailed flowchart of a noise processing method for an inertial navigation system provided by the present invention;

[0046] Figure 3 A diagram of a noise processing device for an inertial navigation system provided by the present invention;

[0047] Figure 4 A schematic diagram of a computer device for a noise processing method of an inertial navigation system provided by the present invention. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0049] The technical solutions provided by the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0050] Figure 1 This is a schematic flowchart of a noise processing method for an inertial navigation system according to the present invention, which specifically includes the following steps:

[0051] S101: Conduct random vibration tests on the inertial navigation system to obtain random vibration test data.

[0052] In one exemplary embodiment, the inertial navigation system is mounted on a vibration table for random vibration testing, and the random vibration test data is recorded.

[0053] S102: Perform noise band tests on random vibration test data under low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges.

[0054] In an exemplary embodiment, noise band testing is performed on random vibration test data under low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges. Specifically, this includes: obtaining the initial cutoff frequency of the low-pass filter and determining the transfer function of the low-pass filter at the initial cutoff frequency; inputting the random vibration test data into the designed low-pass filter and recording the time-domain signal amplitude ratio of the random vibration test data before and after low-pass filter processing; adjusting the initial cutoff frequency of the low-pass filter by a first preset step size increment and determining the low-pass filter transfer function updated to the corresponding initial cutoff frequency; inputting the random vibration test data into the low-pass filter with the updated initial cutoff frequency and recording the time-domain signal amplitude ratio of the random vibration test data before and after low-pass filter processing with the updated initial cutoff frequency; when the output frequency of the inertial navigation system has an initial cutoff frequency greater than a preset multiple, comparing the time-domain signal amplitude ratios under any adjacent initial cutoff frequency setting; if the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial cutoff frequency setting exceeds a first preset threshold, then the frequency range between adjacent initial cutoff frequencies is determined as the initial noise band range.

[0055] The first preset step size, the first preset threshold, and the preset multiple can be set according to specific engineering practices; for example, the first preset step size is 10, the first preset threshold is 1 / 3, and the preset multiple is 0.5.

[0056] Specifically, the basic model for noise filtering in an inertial navigation system consists of a low-pass filter and multiple notch filters.

[0057] Low-pass filters are typically designed using a second-order digital low-pass filter design method. The design transfer function of a second-order digital low-pass filter is shown in Equation (1).

[0058]

[0059] Where U1(s) is the filter output signal, I1(s) is the filter input signal, ε is the low-pass filter design parameter, and ω c Design the cutoff frequency for the low-pass filter.

[0060] The transfer function of the notch filter is shown in Equation (2).

[0061]

[0062] Where ε1 and ε2 are the design parameters of the notch filter, ω cR This is the design frequency for the notch filter.

[0063] Noise band testing was conducted on random vibration test data of the inertial navigation system. Based on the environmental requirements of the inertial navigation system, noise signal tests were performed using low-pass filters with different initial cutoff frequencies. Taking a first preset step size of 10, a preset multiplier of 0.5, and a first preset threshold of 1 / 3 as an example, the test method is as follows:

[0064] (1) Determine the initial cutoff frequency ω1 of the low-pass filter, and design the transfer function of the low-pass filter at this frequency, as shown in formula (1). In formula (1), ω c The value of is the initial cutoff frequency of the low-pass filter.

[0065] (2) Pass the random vibration test data of the inertial navigation system through the designed low-pass filter and record the time domain signal amplitude ratio of the random vibration test data before and after filtering.

[0066] (3) Adjust the initial cutoff frequency of the low-pass filter to ω2=ω1+10, design the transfer function of the low-pass filter at this frequency, and record the time-domain signal amplitude ratio of the random vibration test data before and after filtering after updating the initial cutoff frequency of the low-pass filter.

[0067] (4) Adjust the initial cutoff frequency of the low-pass filter in increments of 10, and determine the transfer function of the low-pass filter after the corresponding initial cutoff frequency update. Record the time-domain signal amplitude ratio of the random vibration test data before and after the frequency update until the initial cutoff frequency of the designed low-pass filter is greater than 0.5 times the output frequency of the inertial navigation system.

[0068] (5) Compare the ratio of the time domain signal amplitude before and after filtering of random vibration test data of inertial navigation system under different initial cutoff frequency settings. If the absolute value of the difference between the two ratios exceeds 1 / 3, it is considered that the output of aliasing frequency noise is within this frequency band range. That is, the frequency range between the two corresponding initial cutoff frequencies is determined as the initial noise frequency band range.

[0069] For example, if the initial cutoff frequencies of the selected low-pass filter are ω1, ω2, ω3, and ω4 respectively, and the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial cutoff frequencies exceeds a first preset threshold, then the frequency range between adjacent initial frequencies is determined as the initial noise frequency band range. For example, first, compare whether the absolute value of the difference between the time-domain signal amplitude ratios under ω1 and ω2 exceeds 1 / 3. If the absolute value of the difference between the time-domain signal amplitude ratios under ω1 and ω2 exceeds 1 / 3, then (ω1, ω2) is determined as the initial noise frequency band range. Following the same principle, compare ω2 and ω3, ω3 and ω4 in sequence to determine multiple initial noise ranges.

[0070] S103: Under each initial noise frequency band, the noise frequency band of the random vibration test data is tested by notch filters with different initial frequencies to obtain multiple target noise frequency bands; the target noise frequency band is the noise frequency band generated by the frequency aliasing effect.

[0071] In an exemplary embodiment, under each initial noise frequency band, noise band tests are performed on random vibration test data using notch filters with different initial frequencies to obtain multiple target noise frequency bands. Specifically, this includes: for any initial noise frequency band, the minimum frequency within the initial noise frequency band is used as the initial frequency of the notch filter; the random vibration test data is input into the parameter-designed notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after notch filter processing is recorded; the initial frequency of the notch filter is adjusted by a second preset step increment to obtain a frequency-updated notch filter, and the random vibration test data is input into the frequency-updated notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after frequency-updated notch filter processing is recorded; when the updated initial frequency is the maximum frequency within the initial noise frequency band, the time-domain signal amplitude ratio under any adjacent initial frequency setting is compared. If the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial frequency settings exceeds a second preset threshold, then the frequency range between adjacent initial frequencies is determined as the target noise frequency band range.

[0072] The second preset step size and the second preset threshold can be set according to specific engineering practices. For example, the second preset step size can be 1, the second preset threshold can be 1 / 5, and the second preset threshold is less than the first preset threshold.

[0073] Specifically, the frequency band design of the notch filter is carried out. Based on the multiple initial noise frequency bands determined in S102, the notch filter is designed for these fixed frequency bands. Taking an initial noise frequency band range, with a second preset step size of 1 and a second preset threshold of 1 / 5 as an example, the design method is as follows:

[0074] (1) Based on the determined initial noise frequency band, confirm the target noise frequency band of the inertial navigation system output, and determine the initial frequency of the notch filter as ω. cR1 Simultaneously, the bandwidth parameters of a notch filter with a bandwidth of 1 Hz are designed; the initial frequency is the minimum frequency within the initial noise bandwidth range.

[0075] (2) Pass the random vibration test data through the designed notch filter and record the ratio of the time domain signal amplitude of the random vibration test data before and after filtering.

[0076] (3) Update the initial frequency of the notch filter to ω. cR2 =ω cR1 +1, and design a notch filter with a frequency band of 1 Hz. Input the random vibration test data into the notch filter with updated frequency after parameter design, and record the time domain signal amplitude ratio of the random vibration test data before and after filtering.

[0077] (4) Stop frequency updating when the difference between the updated initial frequency and the notch filter initial frequency is 10.

[0078] It should be noted that in this embodiment, the difference between the updated initial frequency and the initial frequency of the notch filter is 10. This is because the difference between the minimum and maximum values ​​of the initial noise frequency range is 10, which actually updates the initial frequency to the maximum frequency of the initial noise frequency range.

[0079] (5) If the absolute value of the difference between the time domain signal amplitude ratios under different initial frequency settings exceeds 1 / 5, then the frequency range between different initial frequencies is determined as the target noise frequency band range.

[0080] For example, the initial frequencies of the selected notch filter are ω. 11 ω 12 ω 13 and ω 14 If the absolute value of the difference between the time-domain signal amplitude ratios of adjacent initial frequencies exceeds a second preset threshold, then the frequency range between adjacent initial frequencies is determined as the target noise frequency band; for example, first compare ω 11 and ω 12 Does the absolute value of the difference between the time-domain signal amplitude ratios exceed 1 / 5? If ω 11 and ω 12 If the absolute value of the difference between the time-domain signal amplitude ratios exceeds 1 / 5, then (ω) 11 ω 12 The target noise frequency band is determined; then, following the same principle, ω is compared sequentially. 12 and ω 13 ω 13 and ω 14 This is used to determine the noise range of multiple targets.

[0081] S104: Design the parameters of the notch filter within the target noise frequency band for each target noise frequency band to obtain the target notch filter; and use the target notch filter to filter out the noise signal within the target noise frequency band in the output data of the inertial navigation system.

[0082] In an exemplary embodiment, the notch filter parameters include a first notch parameter and a second notch parameter. For each target noise frequency band, the notch filter parameters are designed to obtain a target notch filter. Specifically, this includes: for any target noise frequency band, determining the center of the target noise frequency band as the center frequency of the notch filter, and obtaining a first initial value for the first notch parameter and a second initial value for the second notch parameter; while keeping the first initial value unchanged, adjusting the second initial value by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the second initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the second notch parameter; keeping the value of the second notch parameter unchanged, adjusting the first initial value by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the first initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the first notch parameter; and obtaining the target notch filter based on the values ​​of the first and second notch parameters.

[0083] The process of adjusting the second initial value with a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions includes: adjusting the second initial value incrementally with the third preset step size; if the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the second initial value, then adjusting the second initial value incrementally with the third preset step size until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the second initial value is stopped. Similarly, adjusting the first initial value with a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions includes: adjusting the first initial value incrementally with the third preset step size; if the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the first initial value, then adjusting the first initial value incrementally with the third preset step size until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the first initial value is stopped.

[0084] The value of the third preset step can be set according to the actual situation, and is not limited in this embodiment.

[0085] Specifically, based on the determined target noise frequency band, a corresponding notch filter is designed to remove noise from the inertial navigation system while fully preserving the effective signal of the inertial navigation system. Taking a third preset step size of 0.001 as an example, the notch filter parameters are set as follows:

[0086] (1) Based on the determined target noise frequency band range, select the midpoint of the target noise frequency band range as the center frequency of the notch filter, and initialize the first initial value ε1 of the first notch parameter and the second initial value ε2 of the second notch parameter of the notch filter.

[0087] (2) While keeping the first initial value ε1 unchanged, adjust the second initial value ε2 to make the ratio of the filtered noise signal to the original output signal under random vibration conditions the minimum. During the judgment process, if the ratio continues to increase, adjust ε2 = ε2 + 0.001, otherwise adjust ε2 = ε2 - 0.001. Stop adjusting the second initial value when the ratio of the filtered noise signal to the original signal under random vibration conditions shows a trend of increasing from small to large. At this time, the filtering effect is optimal. The second initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal is determined as the value of the second notch parameter.

[0088] (3) After ε2 is adjusted, keep the value of the second notch parameter unchanged. Similarly, adjust the first initial value ε1 according to the ratio before and after filtering. If the ratio continues to increase, adjust ε1 = ε1 - 0.001, otherwise adjust ε1 = ε1 + 0.001. Stop adjusting the first initial value when the ratio of the filtered noise signal to the original signal under random vibration conditions shows a trend of increasing from small to large. At this time, the filtering effect is optimal. The first initial value corresponding to the smallest ratio of the filtered noise signal to the original output signal is determined as the value of the first notch parameter.

[0089] (4) Complete the design of notch filters in multiple target noise frequency bands to obtain target notch filters.

[0090] It should be noted that there can be multiple target notch filters. Multiple notch filters are designed in series, and noise signals are filtered through multiple target notch filters designed in series. For example, the target notch filters include a first target notch filter and a second target notch filter. The original output signal of the inertial navigation system can be input to the first target notch filter to obtain the first filtered signal output by the first target notch filter. The first filtered signal is then input to the second target notch filter to obtain the second filtered signal output by the second notch filter. The second filtered signal is determined as the filtered noise signal output by the target filter.

[0091] In one exemplary embodiment, after obtaining the target notch filter, a random vibration test is performed on the inertial navigation system to determine the noise processing performance of the target notch filter. The target notch filter is the noise processing component of the inertial navigation system.

[0092] Based on the determined notch filter design parameters, discretization programming design is carried out. The filter design parameters are shown in formula (4).

[0093]

[0094] Based on the design results, the output calculation method of the inertial navigation system after noise processing is shown in formula (5).

[0095]

[0096] in, Δt is the discretization time step. This is the output of the noise processing of the inertial navigation system at the current moment. Output of noise processing of the inertial navigation system at the current moment This is the input for the noise processing of the inertial navigation system at the previous moment. This is the input for noise processing of the inertial navigation system at the previous time step. This is the output of the noise processing of the inertial navigation system at the previous moment. This is the output of the noise processing of the inertial navigation system at the previous time step.

[0097] In one exemplary embodiment, as follows: Figure 2 The diagram illustrates a specific flowchart of a noise processing method for an inertial navigation system. The inertial navigation device is the inertial navigation system itself. The process includes: setting up the basic filtering model for the inertial navigation system, including a digital low-pass filter and multiple notch filters; conducting random vibration tests on a vibration table; performing frequency band testing based on the random vibration test data; initializing the cutoff frequency of the low-pass filter and increasing it in 10Hz steps, recording the input-output time-domain signal amplitude ratio at each frequency; stopping frequency updates when the cutoff frequency exceeds 0.5 times the data output frequency; recording the frequency band range and designing initial values ​​for the notch filters when the recorded input-output time-domain signal amplitude ratio exceeds a set value; and then increasing the frequency band in 1Hz steps. A notch filter is designed with a step size of 1 Hz and a notch bandwidth of 1 Hz. Random vibration test data is input into the notch filter, and the ratio of the input and output time-domain signal amplitudes is recorded. If the absolute value of the difference between the time-domain signal amplitude ratios exceeds the set value, the frequency range is confirmed as the notch frequency range. The notch center frequency is confirmed, and ε1 is kept constant while ε2 is adjusted. ε2 is updated with a step size of 0.001 until the filter output-input ratio is less than the threshold. After confirming ε2, ε2 is kept constant while ε1 is adjusted with a step size of 0.001 until the filter output-input ratio is less than the threshold. The noise filtering model is discretized and programmed.

[0098] When applying the noise processing method for an inertial navigation system provided by this invention, it is not necessary to consider... Figure 1 The steps shown are executed in sequence. The specific execution order of each step can be determined as needed, and this invention does not impose any restrictions on it.

[0099] The above describes a noise processing method for an inertial navigation system according to the present invention. Based on the same idea, the present invention also provides a corresponding noise processing device for an inertial navigation system, such as... Figure 3 As shown.

[0100] Figure 3 A schematic diagram of a noise processing device for an inertial navigation system provided by the present invention includes:

[0101] The acquisition module 301 is used to acquire random vibration test data obtained from random vibration tests on the inertial navigation system;

[0102] The first processing module 302 is used to perform noise frequency band testing on random vibration test data under low-pass filters with different initial cutoff frequencies, and to determine multiple initial noise frequency band ranges.

[0103] The second processing module 303 is used to perform noise band testing of the random vibration test data with notch filters at different initial frequencies under each initial noise band range, to obtain multiple target noise band ranges; the target noise band range is the noise band range generated by the frequency aliasing effect.

[0104] The third processing module 304 is used to design the notch filter parameters for each target noise frequency band to obtain the target notch filter; and to use the target notch filter to filter out noise signals in the target noise frequency band of the inertial navigation system output data.

[0105] For specific limitations regarding the noise processing device for an inertial navigation system, please refer to the limitations of the noise processing method for an inertial navigation system described above, which will not be repeated here. Each module in the aforementioned noise processing device for an inertial navigation system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0106] The present invention also provides a computer-readable storage medium storing a computer program that can be used to execute the above-described... Figure 1 A noise processing method for an inertial navigation system is provided.

[0107] The present invention also provides Figure 4 The schematic diagram of the computer device shown is as follows: Figure 4As shown, at the hardware level, this computer device includes a processor, internal bus, network interface, memory, and non-volatile memory, and may also include other hardware required for business operations. The processor reads the corresponding computer program from the non-volatile memory into memory and then executes it to achieve the above. Figure 1 A noise processing method for an inertial navigation system is provided.

[0108] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0109] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this invention.

Claims

1. A noise processing method for an inertial navigation system, characterized in that, include: Random vibration tests were conducted on the inertial navigation system to obtain random vibration test data; The noise frequency band of the random vibration test data was tested under low-pass filters with different initial cutoff frequencies to determine multiple initial noise frequency band ranges. Under each initial noise frequency band, the noise frequency band of the random vibration test data is tested using a notch filter with different initial frequencies to obtain multiple target noise frequency bands; the target noise frequency band is the noise frequency band generated by the frequency aliasing effect. For each target noise frequency band, the parameters of the notch filter within the target noise frequency band are designed to obtain the target notch filter; and the target notch filter is used to filter out the noise signal within the target noise frequency band in the output data of the inertial navigation system. The random vibration test data is subjected to noise band testing under low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges. Specifically, this includes: obtaining the initial cutoff frequency of the low-pass filter and determining the transfer function of the low-pass filter at the initial cutoff frequency; inputting the random vibration test data into the designed low-pass filter and recording the time-domain signal amplitude ratio of the random vibration test data before and after processing by the low-pass filter; adjusting the initial cutoff frequency of the low-pass filter by a first preset step size increment and determining the transfer function of the low-pass filter after updating the corresponding initial cutoff frequency; inputting the random vibration test data into the low-pass filter after updating the initial cutoff frequency and recording the time-domain signal amplitude ratio of the random vibration test data before and after processing by the low-pass filter after updating the initial cutoff frequency; when the output frequency of the inertial navigation system has an initial cutoff frequency greater than a preset multiple, comparing the time-domain signal amplitude ratio under any adjacent initial cutoff frequency setting; if the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial cutoff frequency settings exceeds a first preset threshold, then the frequency range between the adjacent initial cutoff frequencies is determined as the initial noise band range. In each initial noise frequency band, the random vibration test data is tested for noise frequency bands using notch filters with different initial frequencies to obtain multiple target noise frequency bands. Specifically, this includes: for any initial noise frequency band, the minimum frequency within the initial noise frequency band is used as the initial frequency of the notch filter; the random vibration test data is input into the parameter-designed notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after processing by the notch filter is recorded; the initial frequency of the notch filter is adjusted by a second preset step increment to obtain a frequency-updated notch filter, and the random vibration test data is input into the frequency-updated notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after processing by the frequency-updated notch filter is recorded; when the updated initial frequency is the maximum frequency within the initial noise frequency band, the time-domain signal amplitude ratio under any adjacent initial frequency setting is compared. If the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial frequency settings exceeds a second preset threshold, then the frequency range between the adjacent initial frequencies is determined as the target noise frequency band range. The notch filter parameters include a first notch parameter and a second notch parameter. The step of designing the notch filter parameters for each target noise frequency band to obtain a target notch filter includes: for any target noise frequency band, determining the center of the target noise frequency band as the center frequency of the notch filter, and obtaining a first initial value for the first notch parameter and a second initial value for the second notch parameter; while keeping the first initial value unchanged, adjusting the second initial value by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the second initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the second notch parameter; keeping the value of the second notch parameter unchanged, adjusting the first initial value by the third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the first initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the first notch parameter; and obtaining the target notch filter based on the values ​​of the first and second notch parameters.

2. The method as described in claim 1, characterized in that, The step of adjusting the second initial value with a third preset step size until the ratio of the filtered noise signal to the original output signal under random vibration conditions is minimized includes: The second initial value is adjusted by the third preset step size increment. If the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the second initial value, the second initial value is adjusted by the third preset step size decrease until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the second initial value is stopped.

3. The method as described in claim 1, characterized in that, Adjusting the first initial value with the third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions includes: The first initial value is adjusted by the third preset step size increment. If the ratio of the filtered noise signal to the original output signal increases during the incremental adjustment of the first initial value, the first initial value is adjusted by the third preset step size decrease until the ratio of the filtered noise signal to the original output signal shows a trend of increasing from small to large, at which point the adjustment of the first initial value is stopped.

4. The method as described in claim 1, characterized in that, The method further includes: After obtaining the target notch filter, a random vibration test is conducted on the inertial navigation system to determine the noise processing performance of the target notch filter, which is the noise processing part of the inertial navigation system.

5. A noise processing device for an inertial navigation system, characterized in that, include: The acquisition module is used to acquire random vibration test data obtained from random vibration tests on inertial navigation systems. The first processing module is used to perform noise band testing on the random vibration test data under low-pass filters with different initial cutoff frequencies, and to determine multiple initial noise band ranges. The second processing module is used to perform noise band testing of the random vibration test data with notch filters at different initial frequencies under each initial noise band range, so as to obtain multiple target noise band ranges. The third processing module is used to design the parameters of the notch filter within each target noise frequency band to obtain the target notch filter; and to use the target notch filter to filter out the noise signal within the target noise frequency band in the output data of the inertial navigation system. The random vibration test data is subjected to noise band testing under low-pass filters with different initial cutoff frequencies to determine multiple initial noise band ranges. Specifically, this includes: obtaining the initial cutoff frequency of the low-pass filter and determining the transfer function of the low-pass filter at the initial cutoff frequency; inputting the random vibration test data into the designed low-pass filter and recording the time-domain signal amplitude ratio of the random vibration test data before and after processing by the low-pass filter; adjusting the initial cutoff frequency of the low-pass filter by a first preset step size increment and determining the transfer function of the low-pass filter after updating the corresponding initial cutoff frequency; inputting the random vibration test data into the low-pass filter after updating the initial cutoff frequency and recording the time-domain signal amplitude ratio of the random vibration test data before and after processing by the low-pass filter after updating the initial cutoff frequency; when the output frequency of the inertial navigation system has an initial cutoff frequency greater than a preset multiple, comparing the time-domain signal amplitude ratio under any adjacent initial cutoff frequency setting; if the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial cutoff frequency settings exceeds a first preset threshold, then the frequency range between the adjacent initial cutoff frequencies is determined as the initial noise band range. In each initial noise frequency band, the random vibration test data is tested for noise frequency bands using notch filters with different initial frequencies to obtain multiple target noise frequency bands. Specifically, this includes: for any initial noise frequency band, the minimum frequency within the initial noise frequency band is used as the initial frequency of the notch filter; the random vibration test data is input into the parameter-designed notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after processing by the notch filter is recorded; the initial frequency of the notch filter is adjusted by a second preset step increment to obtain a frequency-updated notch filter, and the random vibration test data is input into the frequency-updated notch filter, and the time-domain signal amplitude ratio of the random vibration test data before and after processing by the frequency-updated notch filter is recorded; when the updated initial frequency is the maximum frequency within the initial noise frequency band, the time-domain signal amplitude ratio under any adjacent initial frequency setting is compared. If the absolute value of the difference between the time-domain signal amplitude ratios under adjacent initial frequency settings exceeds a second preset threshold, then the frequency range between the adjacent initial frequencies is determined as the target noise frequency band range. The notch filter parameters include a first notch parameter and a second notch parameter. The step of designing the notch filter parameters for each target noise frequency band to obtain a target notch filter includes: for any target noise frequency band, determining the center of the target noise frequency band as the center frequency of the notch filter, and obtaining a first initial value for the first notch parameter and a second initial value for the second notch parameter; while keeping the first initial value unchanged, adjusting the second initial value by a third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the second initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the second notch parameter; keeping the value of the second notch parameter unchanged, adjusting the first initial value by the third preset step size until the ratio of the filtered noise signal to the original output signal is minimized under random vibration conditions, and determining the first initial value corresponding to the minimum ratio of the filtered noise signal to the original output signal as the value of the first notch parameter; and obtaining the target notch filter based on the values ​​of the first and second notch parameters.

6. A computer-readable storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, implements the method as described in any one of claims 1 to 4.

7. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method as described in any one of claims 1 to 4.

Images