CN114400986A - Cascade filtering method and device for portable relative gravimeter - Google Patents
Cascade filtering method and device for portable relative gravimeter Download PDFInfo
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- CN114400986A CN114400986A CN202111486896.5A CN202111486896A CN114400986A CN 114400986 A CN114400986 A CN 114400986A CN 202111486896 A CN202111486896 A CN 202111486896A CN 114400986 A CN114400986 A CN 114400986A
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- 238000001914 filtration Methods 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000005070 sampling Methods 0.000 claims abstract description 51
- 238000005259 measurement Methods 0.000 claims abstract description 24
- 230000005484 gravity Effects 0.000 claims description 64
- 238000005096 rolling process Methods 0.000 claims description 11
- 238000003860 storage Methods 0.000 claims description 8
- 238000004364 calculation method Methods 0.000 claims description 7
- 238000012545 processing Methods 0.000 abstract description 12
- 238000010586 diagram Methods 0.000 description 13
- 238000004590 computer program Methods 0.000 description 11
- 230000008569 process Effects 0.000 description 6
- 238000012986 modification Methods 0.000 description 5
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- 238000005516 engineering process Methods 0.000 description 4
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H17/00—Networks using digital techniques
- H03H17/02—Frequency selective networks
- H03H17/0283—Filters characterised by the filter structure
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V7/00—Measuring gravitational fields or waves; Gravimetric prospecting or detecting
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H17/00—Networks using digital techniques
- H03H17/02—Frequency selective networks
- H03H17/06—Non-recursive filters
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H17/00—Networks using digital techniques
- H03H2017/0072—Theoretical filter design
- H03H2017/0081—Theoretical filter design of FIR filters
Abstract
The invention relates to a cascade filtering method and a device of a portable relative gravimeter, and the scheme comprises two-stage filtering, wherein the output data of the gravimeter is subjected to down-sampling, and then the down-sampled output data of the gravimeter is sent to an FIR filter for filtering to obtain the final output result of the gravimeter. Through the technical scheme, the output precision of the gravimeter is high, the down-sampling treatment of the cascade filter can inhibit high-frequency noise in advance, and the measurement precision is improved. Meanwhile, the scheme saves computing resources, and the order of the filter can be reduced through the down-sampling processing of the cascade filter, so that the operation pressure is reduced.
Description
Technical Field
The invention relates to the technical field of surveying and mapping, in particular to a cascade filtering method and device of a portable relative gravimeter.
Background
The portable relative gravimeter is used as a measuring instrument capable of sensing environmental gravity information, can directly reflect the spatial distribution characteristics of mineral resources so as to provide convenience for resource exploration and utilization, and can also provide original reference gravity information for military striking. However, in the actual gravity measurement process, the external motion disturbance is often coupled with the gravity field and is simultaneously measured by the gravity sensor, thereby causing measurement errors. Therefore, an effective method capable of separating the motion disturbance from the actual gravity field needs to be adopted to improve the gravity measurement precision.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention provides a cascade filtering method and a cascade filtering device for a portable relative gravimeter, which can solve the problem that the measurement precision of the portable relative gravimeter is influenced by motion disturbance.
The technical scheme for solving the technical problems is as follows:
in a first aspect, the present invention provides a method for cascading filtering of a portable relative gravimeter, including:
down-sampling the output data of the gravimeter;
and sending the output data of the gravity meter after the down sampling into an FIR filter for filtering to obtain a final output result of the gravity meter.
Further, the gravimeter is digitally leveled prior to the gravimeter measurement.
Further, the digital leveling of the gravimeter comprises:
according to the Euler angle definition, the output value of the gravity meter and the pitching and rolling states of the equipment have the following relations:
wherein [ a ] isx ay az]The output value of the gravimeter is g, the reference gravity is g, the pitch to be solved of the equipment is alpha, and the roll to be solved of the equipment is beta;
and the relation between the output value of the gravity meter and the pitching and rolling states of the equipment is utilized to complete pitching and rolling calculation and realize digital leveling.
Further, down-sampling the gravimeter output data includes: down-sampling the gravimeter output data according to the following formula:
in the formula (f)smoothIs a down-sampling result; f. ofiThe gravity signal is an original gravity signal in the day direction at the moment i; n is the down-sampling time span.
Further, the down-sampling time span N is taken to be 1 s.
Further, the cut-off frequency f of the FIR filtersCalculated by the following formula:
d＝0.5×v×(1/fs)
in the formula: d is the spatial resolution of the gravimeter and v is the average horizontal movement velocity of the gravimeter carrier.
In a second aspect, the present invention provides a cascade filter device for a portable relative gravimeter, comprising:
the down-sampling module is used for down-sampling the data output by the gravimeter;
and the FIR filter module is used for filtering the gravity meter output data after the down sampling to obtain the final output result of the gravity meter.
Further, the device also comprises a digital leveling module which is used for carrying out digital leveling on the gravimeter before the gravimeter measures.
In a third aspect, the present invention provides an electronic device comprising:
a memory for storing a computer software program;
and the processor is used for reading and executing the computer software program so as to realize the cascade filtering method of the portable relative gravimeter according to the first aspect of the invention.
In a fourth aspect, the present invention provides a non-transitory computer readable storage medium having stored therein a computer software program for implementing the method of cascaded filtering for a portable relative gravimeter according to the first aspect of the present invention.
The invention has the beneficial effects that: the invention comprises two stages of low-pass filters, wherein the first stage of low-pass filter is used for realizing data down-sampling, and the second stage of low-pass filter is used for finishing gravity measurement filtering. The technology can be used for gravity measurement filtering of a portable relative gravimeter and has certain engineering value.
Considering that the gravity information is in a low frequency band, namely the mean value is down sampled and the effective gravity information is not attenuated, the data processing flow adopts a flow sequential processing mode. After original gravity information is measured, mean value down-sampling is carried out on high-frequency sampling data in advance, and disturbance influence is initially inhibited; and then, the low-frequency gravity data after down sampling is processed by an FIR low-pass filter to complete gravity calculation.
Through the technical scheme, the output precision of the gravimeter is high, the down-sampling treatment of the cascade filter can inhibit high-frequency noise in advance, and the measurement precision is improved. Meanwhile, the scheme saves computing resources, and the order of the filter can be reduced through the down-sampling processing of the cascade filter, so that the operation pressure is reduced.
Drawings
Fig. 1 is a schematic structural diagram of a cascade filter device of a portable relative gravimeter according to an embodiment of the present invention;
fig. 2 is a schematic flow chart of a cascade filtering method of a portable relative gravimeter according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of an electronic device according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a non-transitory computer-readable storage medium according to an embodiment of the present invention.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
As shown in fig. 1, an embodiment of the present invention provides a cascade filter device for a portable relative gravimeter. The device comprises a digital leveling module, a down-sampling module and an FIR filter module.
The digital leveling module is used for performing digital leveling on the gravity meter before measurement of the gravity meter;
the down-sampling module is used for down-sampling the output data of the gravimeter;
and the FIR filter module is used for filtering the gravity meter output data after the down sampling to obtain the final output result of the gravity meter.
Based on the device, the embodiment of the invention also provides a cascade filtering method of the portable relative gravimeter, and the flow chart of the method is shown in fig. 2. The method comprises the following steps:
carrying out digital leveling on the gravimeter;
down-sampling the output data of the gravimeter;
and sending the output data of the gravity meter after the down sampling into an FIR filter for filtering to obtain a final output result of the gravity meter.
The portable relative gravimeter adopts three accelerometers as gravity sensors, and digital leveling is required to be completed according to the pitching and rolling states of the equipment in the actual measurement process, so that the output value of the three-axis accelerometer can be correctly projected to the sky direction. According to the Euler angle definition, when the equipment has pitching and rolling, the measured value of the three-axis accelerometer and the pitching and rolling states of the equipment have the following relations:
wherein [ a ] isx ay az]The output value of the gravimeter is g, the reference gravity is g, the pitch to be solved of the equipment is alpha, and the roll to be solved of the equipment is beta;
and the relation between the output value of the gravity meter and the pitching and rolling states of the equipment is utilized to complete pitching and rolling calculation and realize digital leveling.
In the gravity measurement process, a raw sensor signal generally has a high-frequency sampling frequency of 50-500 HZ, and the signal contains high-frequency noise with large amplitude and external disturbance noise. The direct low-pass filtering calculation by using the high-frequency signal not only consumes the calculation resources of the processor seriously, but also causes the phenomenon that the low-frequency gravity information cannot be reflected correctly, and is not favorable for attenuation suppression of high-frequency disturbance. Therefore, it is necessary to adopt a down-sampling technique to process the raw data of the sensor:
in the formula (f)smoothIs a down-sampling result; f. ofiThe gravity signal is an original gravity signal in the day direction at the moment i; n is the down-sampling time span.
To fit satellite navigation measurements, which are typically at 1Hz sampling frequency, N is typically chosen to be 1 s. After the down-sampling technology is adopted, the suppression of high-frequency noise can be directly realized, and the subsequent gravity measurement filtering processing can be facilitated.
In order to further increase the accuracy of the gravity measurement result, it is necessary to design a low-pass filter for gravity measurement based on the down-sampling result based on the frequency band characteristics and measurement requirements of the gravity information. Currently, scholars mainly use finite impulse response filters (FIR filters) to implement gravity measurement, and the FIR filters can be equivalent to a differential equation form convenient for encoding implementation:
in the formula: a isk,bkIs the filter coefficient; m and N jointly form the order of the filter; x () is the input sequence; y () is the output sequence. In the process of actually applying the FIR filter, the spatial resolution requirement (or referred to as half-wavelength resolution) of the gravity measurement result needs to be combined, and the spatial resolution of the gravimeter is as follows:
d＝0.5×v×(1/fs)
in the formula: d is the spatial resolution of the gravimeter, v is the average horizontal movement velocity of the gravimeter carrier, fsThe frequency is cut for a filter corresponding to an attenuation gain of-3 dB.
Spatial resolution defined by the cut-off frequency fsDetermine, and fsThe cut-off frequency f of the filter can be calculated according to the average motion speed v when the carrier measures gravity with the required spatial resolution d as inputs。
For motion disturbance suppression, a mainstream solution is to separate motion acceleration from gravity based on signal frequency domain characteristics starting from a low-pass digital filter. Based on the technical scheme, the portable cascade filtering technology for the relative gravimeter comprises two stages of low-pass filters, wherein the first stage of low-pass filter is used for achieving data down-sampling, and the second stage of low-pass filter is used for achieving gravity measurement filtering. The technology can be used for gravity measurement filtering of a portable relative gravimeter and has certain engineering value.
Considering that the gravity information is in a low frequency band, namely the mean value is down sampled and the effective gravity information is not attenuated, the data processing flow adopts a flow sequential processing mode. After original gravity information is measured, mean value down-sampling is carried out on high-frequency sampling data in advance, and disturbance influence is initially inhibited; and then, the low-frequency gravity data after down sampling is processed by an FIR low-pass filter to complete gravity calculation.
Through the technical scheme, the output precision of the gravimeter is high, the down-sampling treatment of the cascade filter can inhibit high-frequency noise in advance, and the measurement precision is improved. Meanwhile, the scheme saves computing resources, and the order of the filter can be reduced through the down-sampling processing of the cascade filter, so that the operation pressure is reduced.
Referring to fig. 3, fig. 3 is a schematic diagram of an embodiment of an electronic device according to an embodiment of the invention. As shown in fig. 3, an embodiment of the present invention provides an electronic device 500, which includes a memory 510, a processor 520, and a computer program 511 stored in the memory 520 and executable on the processor 520, wherein the processor 520 executes the computer program 511 to implement the following steps:
down-sampling the output data of the gravimeter;
and sending the output data of the gravity meter after the down sampling into an FIR filter for filtering to obtain a final output result of the gravity meter.
Referring to fig. 4, fig. 4 is a schematic diagram illustrating an embodiment of a computer-readable storage medium according to the present invention. As shown in fig. 4, the present embodiment provides a computer-readable storage medium 600 having a computer program 611 stored thereon, the computer program 611, when executed by a processor, implementing the steps of:
down-sampling the output data of the gravimeter;
and sending the output data of the gravity meter after the down sampling into an FIR filter for filtering to obtain a final output result of the gravity meter.
It should be noted that, in the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to relevant descriptions of other embodiments for parts that are not described in detail in a certain embodiment.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A cascade filtering method of a portable relative gravimeter is characterized by comprising the following steps:
down-sampling the output data of the gravimeter;
and sending the output data of the gravity meter after the down sampling into an FIR filter for filtering to obtain a final output result of the gravity meter.
2. The method of claim 1, wherein the gravimeter is digitally leveled prior to the gravimeter measurement.
3. The method of claim 2, wherein the digitally leveling the gravimeter comprises:
according to the Euler angle definition, the output value of the gravity meter and the pitching and rolling states of the equipment have the following relations:
wherein [ a ] isx ay az]The output value of the gravimeter is g, the reference gravity is g, the pitch to be solved of the equipment is alpha, and the roll to be solved of the equipment is beta;
and the relation between the output value of the gravity meter and the pitching and rolling states of the equipment is utilized to complete pitching and rolling calculation and realize digital leveling.
4. The method of claim 1, wherein down-sampling the gravimeter output data comprises: down-sampling the gravimeter output data according to the following formula:
in the formula (f)smoothIs a down-sampling result; f. ofiThe gravity signal is an original gravity signal in the day direction at the moment i; n is the down-sampling time span.
5. The method of claim 4, wherein the downsampled time span N is taken to be 1 s.
6. Method according to claim 1, characterized in that the cut-off frequency f of the FIR filtersCalculated by the following formula:
d＝0.5×v×(1/fs)
in the formula: d is the spatial resolution of the gravimeter and v is the average horizontal movement velocity of the gravimeter carrier.
7. A cascaded filter arrangement for a portable relative gravimeter, comprising:
the down-sampling module is used for down-sampling the data output by the gravimeter;
and the FIR filter module is used for filtering the gravity meter output data after the down sampling to obtain the final output result of the gravity meter.
8. The apparatus of claim 7, further comprising a digital leveling module for digitally leveling the gravimeter prior to the gravimeter measurement.
9. An electronic device, comprising:
a memory for storing a computer software program;
a processor for reading and executing the computer software program to implement the cascade filtering method of a portable relative gravimeter according to any of claims 1 to 6.
10. A non-transitory computer readable storage medium having stored therein a computer software program for implementing the method of cascaded filtering for a portable relative gravimeter according to any of claims 1-6.
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- 2021-12-07 CN CN202111486896.5A patent/CN114400986A/en active Pending
Patent Citations (6)
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| CN101083461A (en) * | 2007-07-13 | 2007-12-05 | 北京创毅视讯科技有限公司 | Drop sampling filtering process and drop sampling filter |
| CN102033163A (en) * | 2009-10-06 | 2011-04-27 | 精工爱普生株式会社 | Frequency measurement method, frequency measurement device and apparatus equipped with frequency measurement device |
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