CN107907206A - A kind of intrinsic frequency on-line detecting system - Google Patents
A kind of intrinsic frequency on-line detecting system Download PDFInfo
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- CN107907206A CN107907206A CN201711129491.XA CN201711129491A CN107907206A CN 107907206 A CN107907206 A CN 107907206A CN 201711129491 A CN201711129491 A CN 201711129491A CN 107907206 A CN107907206 A CN 107907206A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H13/00—Measuring resonant frequency
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Abstract
The invention discloses a kind of intrinsic frequency on-line detecting system, include at least：Gather the signal gathering unit of time-domain signal, transmitted the signal collected by the signal gathering unit, the sensor unit being connected with signal gathering unit and the data processing unit for being handled the signal collected.Close mode is individually extracted, is indexed according to its frequency values for the intensive situation of mode present in actual test by the system of the present invention.When being tested in advance workpiece, program finds multimodal occur in investigative range, can extract the band frequency receptance function amplitude curve, to each intrinsic frequency in this section of curve into line label.In test wherein first natural frequency value is asked for according to what label was fixed.
Description
Technical field
The present invention relates to a kind of intrinsic frequency on-line detecting system, belong to frequency detecting field.
Background technology
Intrinsic frequency on-line detecting system has the larger market demand.Mainly there are two kinds of intrinsic frequencies point currently on the market
Analysis method, the first is the judgement that intrinsic frequency is carried out by manual method, its advantage is compared for the effect of close mode
It is good, it can judge the small peak frequency values adjacent with main peak.But it is by manually being analyzed, causing inefficiency, many situations
Under be off-line analysis, the retrospect for substandard product is relatively difficult, and order of accuarcy is difficult to ensure.Second is to pass through system
To be detected, it is detected by computer program efficient, accuracy is good, and constantly analysis avoids the work of data traceability
Journey.Shortcoming be current mainstream multiple systems or by search go to see in the range of amplitude maximum frequency values sentence to carry out system
It is fixed, if can only be maximized there are multiple peak values in section, it is difficult to which fixed asks for fundamental frequency.
Contrast the intrinsic frequency detecting system of forefathers' design, the automatic intrinsic frequency measuring system of brake disc of Hu Lele designs
(CN201520712770.9) to be designed purposes mainly for brake disc relatively single, since braking disk shape is regular, damping
Greatly, its natural frequency value is more open.Close mode identification can not be thus carried out, and using attached caused by acceleration transducer
Quality is added to be impacted to the measured value of workpiece.
A kind of device for detecting inherent frequency of workpiece (CN201110332097.2) of Ji Licheng designs also relies on power hammer and swashs
Hair, but it does not have the processing mode for percussion in the case of undesirable in invention, when the secondary double hit of appearance or measuring point position
Put the erroneous judgement for deviating and easily causing to workpiece.And the same accuracy for employing acceleration transducer, influencing test.
The content of the invention
The it is proposed of the present invention in view of the above problems, this application involves a kind of intrinsic frequency on-line detecting system, it is at least wrapped
Include：Gather time-domain signal signal gathering unit, the signal collected by the signal gathering unit is transmitted with letter
Number the collecting unit sensor unit being connected and the data processing unit for being handled the signal collected.
Wherein, the sensor unit, including：The power being connected with the collecting unit is hammered into shape and is connected with the collecting unit
Industrial microphone；Produced by power hammering workpiece for measurement surface caused by pumping signal, that is, power hammer hammering of transient state
Force signal；The industry microphone obtains the pumping signal produced after workpiece taps, is here sound pressure signal；
The pumping signal that the signal gathering unit collection power hammer hammering workpiece for measurement surface produces, and industrial Mike's elegance
Collect the response signal of Workpiece vibration generation, and two signals are passed into data processing unit；
The hammering signal and the response signal of workpiece that data processing unit hammers power into shape are handled by calculating, obtain consolidating for workpiece
There are frequency values, and then judge workpiece qualification.
Further, using a kind of intrinsic frequency on-line detecting system, comprise the following steps：
S1：Detection demand according to user oneself is configured, response signal when detecting system collection workpiece is hammered
When, acceleration transducer and the industrial two kinds of sensor of microphone start simultaneously at detection；
S2：Parameter configuration is carried out to system, parameter includes at least sample rate, number of taps, driving source；
S3：Standard workpiece is demarcated, delimit the region of search and tolerance interval, protects the information of test after the completion of delimitation
Test file is saved as, it is convenient to call next time；
S4：Capture card enters operating status, power hammer hammering workpiece, and the signal gathering unit collection power hammer hammers what is produced
The response signal that pumping signal and Workpiece vibration produce；
S5：First progress peak value is carried out according to the detection demarcated in the test file and the margin of tolerance to ask for, peak value is asked for
After the completion of by phase transition exclude burr interference, by the natural frequency value of acquirement and in S3The tolerance interval of middle delimitation, which is made comparisons, to be sentenced
Disconnected workpiece qualification, and judge real-time display on the screen qualification；
If certain rank modal excitation is insufficient, show that noise jamming is obvious, system prompt operator taps again；If excitation
It is abundant then the results are shown in the display module.
Further, when searching peak value and when coherence coefficient is more than 0.8, judge to strike according to coherence coefficient size
Whether the quality hit, coherence coefficient represent the correlation of input and output and are intrinsic by the value that phase transition judges to index
Frequency；
Amplitude and phase are carried out separated equation by frequency response function after abbreviation：
Wherein,For i ranks modal frequency ratio, ζiFor i rank damping ratios,Wherein ζiFor i ranks
Damping ratios, KiFor corresponding i-th rank rigidity.
Further, which is industrial microphone and acceleration transducer.
The advantage of the invention is that：The relatively pervious intrinsic frequency test of system mainly has the improvement of the following aspects.
1st, relative to manual search, the system on-line analysis, speed is fast, avoids recalling.
2nd, by amplitude and frequency, rope can be judged when making test file relative to second of system detectio, the system
Take the exponent number at peak, stable pickup peak value.
3rd, relative to other computer detection systems, the system is good for the identification of small damping close mode, and
Its damping ratio can be analyzed in the case of close mode.
4th, test process is stablized, and in the case that appearance percussion is undesirable, prompts operator to tap again.Avoid because striking
Hitting produced problem causes to judge the compliance of workpiece by accident.
5th, system can compatible acceleration transducer and industrial microphone.Compared to most detecting systems on the market using acceleration
Sensor is spent, industrial microphone sensor reduces additional mass, reduces the influence to measurement result.
6th, system is individually extracted close mode, according to its frequency for the intensive situation of mode present in actual test
Value is indexed.When being tested in advance workpiece, program finds multimodal occur in investigative range, can respond the band frequency
Function amplitude curve extracts, to each intrinsic frequency in this section of curve into line label.Fixed in test according to label
Ask for wherein first natural frequency value.
Brief description of the drawings
, below will be to embodiment or existing for clearer explanation the embodiment of the present invention or the technical solution of the prior art
Have technology describe needed in attached drawing do one and simply introduce, it should be apparent that, drawings in the following description are only
Some embodiments of the present invention, for those of ordinary skill in the art, without creative efforts, may be used also
To obtain other attached drawings according to these attached drawings.
Fig. 1 is the system flow schematic diagram of the present invention；
Fig. 2 is the overall structure diagram of the present invention.
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, with reference to the embodiment of the present invention
In attached drawing, the technical solution in the embodiment of the present invention is clearly completely described：
As shown in Figs. 1-2, it is a kind of intrinsic frequency on-line detecting system schematic diagram of the present invention, as preferable embodiment party
Formula, system include at least：Gather time-domain signal signal gathering unit, by by the signal that the signal gathering unit collects into
The sensor unit being connected with signal gathering unit and the data processing for being handled the signal collected that row transmits
Unit.It can be understood as in other embodiments, system can also include the data transmission unit and data of data transfer
Storage unit etc., as long as disclosure satisfy that, can under fixed frequency can also detecting system content, and by the content after detection into
Row display can instruct meal author's operation.
In the present embodiment, the sensor unit includes：The power being connected with the collecting unit is hammered into shape and adopted with described
Collect the industrial microphone of unit connection；Pumping signal, that is, power hammer hammer of transient state is produced by power hammering workpiece for measurement surface
Hit caused force signal；It is sound pressure signal that the industry microphone, which obtains the pumping signal produced after workpiece taps,.
As preferred embodiment, the voltage signal transmitted by collecting unit acquisition sensor unit, is converted by AD
Obtain digital signal.Collecting unit by transformed signal transmission to data processing unit, data processing unit read excitation and
Response signal simultaneously carries out calculating processing.When judging that secondary double hit occurs for pumping signal or hammer force degree is too big or too small, system
Prompt window is ejected, reminds operator to tap again.Completed when tapping, carry out intrinsic frequency identification.In the present embodiment, institute
The pumping signal that signal gathering unit collection power hammer hammering workpiece for measurement surface produces is stated, and industrial microphone collects workpiece and shakes
The response signal of movable property life, and two signals are passed into data processing unit.The hammering signal that data processing unit hammers power into shape
Handled with the response signal of workpiece by calculating, obtain the natural frequency value of workpiece, and then judge workpiece qualification.
As preferred embodiment, using intrinsic frequency on-line detecting system when is further comprising the steps of：
S1：Detection demand according to user oneself is configured, response signal when detecting system collection workpiece is hammered
When, acceleration transducer and the industrial two kinds of sensor of microphone start simultaneously at detection.It is to be understood that in other implementations
In mode, for sensor model number, system does not limit requirement, and user can select to be adapted to oneself according to the test request of oneself
It is required that sensor model number, user self-defined can select, and by the capture card in system, sensor and PC each several parts are connected
Connect.As long as disclosure satisfy that can clearly gather required signal, and be by the signal progress processing after collection and display
Can.
S2：Parameter configuration is carried out to system, parameter includes at least sample rate, number of taps, driving source；
S3：Standard workpiece is demarcated, delimit the region of search and tolerance interval, protects the information of test after the completion of delimitation
It is saved as test file；
S4：Capture card enters operating status, power hammer hammering workpiece, and the signal gathering unit collection power hammer hammers what is produced
The response signal that pumping signal and Workpiece vibration produce；
S5：First progress peak value is carried out according to the detection demarcated in the test file and the margin of tolerance to ask for, peak value is asked for
After the completion of by phase transition exclude burr interference, by the natural frequency value of acquirement and in S3The tolerance interval of middle delimitation, which is made comparisons, to be sentenced
Disconnected workpiece qualification, and judge real-time display on the screen qualification；
If certain rank modal excitation is insufficient, show that noise jamming is obvious, system prompt operator taps again；If excitation
It is abundant then the results are shown in the display module.In the present embodiment, if the insufficient i.e. frequency response function of certain rank modal excitation
Phase transition be not reaching to requirement or coherence coefficient is inadequate, coherence coefficient is for weighing input signal and output signal
Coherence, coherence coefficient height show export signal produced completely by input signal, otherwise input with output coherence it is low,
Then show that noise jamming is obvious.
As preferred embodiment, when searching peak value and when coherence coefficient is more than 0.8, according to coherence coefficient
Size judges the quality tapped, and coherence coefficient represents input and the correlation exported and the value for judging to index by phase transition
Whether it is intrinsic frequency；
Frequency response functionAmplitude and phase are carried out separated equation after abbreviation is：
Wherein,For i ranks modal frequency ratio, ζiFor i rank damping ratios,Wherein ζiFor i ranks
Damping ratios, KiFor corresponding i-th rank rigidity.It can be seen that by (1) formula when transfer curve is reaching intrinsic frequency
When (Tend to 1), due to grIt is small damping structure, it is smaller, thus there is peak value in amplitude.Pass through (2) formula, it can be seen that
When frequency response function passes through formant, the conversion of 0~180 degree is had for undamped structure phase, our research objects
In a variety of brake components its dampings be not very big relatively, when reaching intrinsic frequency, phase also occur one it is larger
Transformation.
In the present embodiment, system compatible two types sensor is industrial microphone and acceleration transducer.Can be with
It is interpreted as in other embodiments, the sensor can also be other sensors, as long as the intrinsic frequency needed for detecting is
Can.
The foregoing is only a preferred embodiment of the present invention, but protection scope of the present invention be not limited thereto,
Any one skilled in the art the invention discloses technical scope in, technique according to the invention scheme and its
Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.
Claims (4)
1. a kind of intrinsic frequency on-line detecting system, it is characterised in that include at least：
Gather the signal gathering unit of time-domain signal, transmitted the signal collected by the signal gathering unit, with
The sensor unit that signal gathering unit is connected and the data processing unit for being handled the signal collected；
Wherein, the sensor unit, including：The power hammer being connected with the collecting unit and the work being connected with the collecting unit
Industry microphone；Pumping signal, that is, power caused by power hammer hammering that transient state is produced by power hammering workpiece for measurement surface is believed
Number；It is sound pressure signal that the industry microphone, which obtains the pumping signal produced after workpiece taps,；
The pumping signal that the signal gathering unit collection power hammer hammering workpiece for measurement surface produces, and industrial microphone collect
The response signal that Workpiece vibration produces, and two signals are passed into data processing unit；
The hammering signal and the response signal of workpiece that data processing unit hammers power into shape are handled by calculating, obtain the intrinsic frequency of workpiece
Rate value, and then judge workpiece qualification.
2. a kind of intrinsic frequency on-line detecting system according to claim 1, it is characterised in that include following step during use
Suddenly：
S1：Detection demand according to user oneself is configured, and when detecting system gathers response signal when workpiece is hammered, is added
Velocity sensor and the industrial two kinds of sensor of microphone start simultaneously at detection；
S2：Parameter configuration is carried out to system, parameter includes at least sample rate, number of taps, driving source；
S3：Standard workpiece is demarcated, delimit the region of search and tolerance interval, after the completion of delimitation by the information of test preserve into
Test file；
S4：Capture card enters operating status, power hammer hammering workpiece, the excitation that the signal gathering unit collection power hammer hammering produces
The response signal that signal and Workpiece vibration produce；
S5：First progress peak value is carried out according to the detection demarcated in the test file and the margin of tolerance to ask for, after the completion of peak value is asked for
Burr interference is excluded by phase transition, by the natural frequency value of acquirement and in S3The tolerance interval of middle delimitation, which is made comparisons, judges workpiece
Qualification, and judge real-time display on the screen qualification；
If certain rank modal excitation is insufficient, show that noise jamming is obvious, system prompt operator taps again；If excitation is abundant
Then the results are shown in the display module.
3. a kind of intrinsic frequency on-line detecting system according to claim 1, is further characterized in that：
When searching peak value and when coherence coefficient is more than 0.8, the quality of percussion is judged according to coherence coefficient size, is concerned with
Whether property coefficient represents the correlation of input and output and is intrinsic frequency by the value that phase transition judges to index；
Frequency response functionAmplitude and phase are carried out separated equation after abbreviation is：
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Wherein,For i ranks modal frequency ratio, ζiFor i rank damping ratios,Wherein ζiFor i rank mode
Damping ratio, KiFor corresponding i-th rank rigidity.
4. a kind of intrinsic frequency on-line detecting system according to claim 1, is further characterized in that：The detecting system is compatible
Two types sensor is industrial microphone and acceleration transducer.
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| CN201711129491.XA CN107907206A (en) | 2017-11-15 | 2017-11-15 | A kind of intrinsic frequency on-line detecting system |
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| CN201711129491.XA CN107907206A (en) | 2017-11-15 | 2017-11-15 | A kind of intrinsic frequency on-line detecting system |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109374070A (en) * | 2018-09-28 | 2019-02-22 | 天津大学 | A kind of vortex-shedding meter measurement method of integrated pipeline intrinsic frequency on-line measurement |
| CN109613117A (en) * | 2018-12-19 | 2019-04-12 | 广州广电计量检测股份有限公司 | Vibrate defectoscope performance parameter preparation method and device |
| CN109632021A (en) * | 2019-01-30 | 2019-04-16 | 天津大学 | A kind of pipeline resonance measuring method for vortex-shedding meter |
| CN109632020A (en) * | 2019-01-30 | 2019-04-16 | 天津大学 | It can exclude the vortex-shedding meter measurement method of resonance interference |
| CN111830062A (en) * | 2020-07-22 | 2020-10-27 | 深圳市赛龙自动化科技有限公司 | Ceramic bottle flaw detection equipment and detection method thereof |
| CN112747915A (en) * | 2021-01-29 | 2021-05-04 | 浙江工业大学 | Spiral tube natural frequency measuring device |
| CN114109798A (en) * | 2021-11-26 | 2022-03-01 | 广东美的暖通设备有限公司 | Frequency determination method, frequency determination device, compressor system and storage medium |
| WO2022118154A1 (en) * | 2020-12-04 | 2022-06-09 | Haute Ecole Arc | Test method for protection equipment |
| CN114822478A (en) * | 2022-03-11 | 2022-07-29 | 中国第一汽车股份有限公司 | Automobile with active noise reduction system for road noise in automobile and vibration signal acquisition device and system development method |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109374070A (en) * | 2018-09-28 | 2019-02-22 | 天津大学 | A kind of vortex-shedding meter measurement method of integrated pipeline intrinsic frequency on-line measurement |
| CN109613117A (en) * | 2018-12-19 | 2019-04-12 | 广州广电计量检测股份有限公司 | Vibrate defectoscope performance parameter preparation method and device |
| CN109613117B (en) * | 2018-12-19 | 2021-11-09 | 广州广电计量检测股份有限公司 | Method and device for obtaining performance parameters of vibration flaw detector |
| CN109632020A (en) * | 2019-01-30 | 2019-04-16 | 天津大学 | It can exclude the vortex-shedding meter measurement method of resonance interference |
| CN109632021A (en) * | 2019-01-30 | 2019-04-16 | 天津大学 | A kind of pipeline resonance measuring method for vortex-shedding meter |
| CN111830062A (en) * | 2020-07-22 | 2020-10-27 | 深圳市赛龙自动化科技有限公司 | Ceramic bottle flaw detection equipment and detection method thereof |
| WO2022118154A1 (en) * | 2020-12-04 | 2022-06-09 | Haute Ecole Arc | Test method for protection equipment |
| CH718128A1 (en) * | 2020-12-04 | 2022-06-15 | Haute Ecole Arc | Method and device for testing protective equipment. |
| CN112747915A (en) * | 2021-01-29 | 2021-05-04 | 浙江工业大学 | Spiral tube natural frequency measuring device |
| CN112747915B (en) * | 2021-01-29 | 2024-05-31 | 浙江工业大学 | Spiral pipe natural frequency measuring device |
| CN114109798A (en) * | 2021-11-26 | 2022-03-01 | 广东美的暖通设备有限公司 | Frequency determination method, frequency determination device, compressor system and storage medium |
| CN114109798B (en) * | 2021-11-26 | 2023-08-29 | 广东美的暖通设备有限公司 | Frequency determining method, frequency determining device, compressor system and storage medium |
| CN114822478A (en) * | 2022-03-11 | 2022-07-29 | 中国第一汽车股份有限公司 | Automobile with active noise reduction system for road noise in automobile and vibration signal acquisition device and system development method |
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