CN109186842A - A kind of cable method for measuring stress based on magnetoelasticity - Google Patents
A kind of cable method for measuring stress based on magnetoelasticity Download PDFInfo
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- CN109186842A CN109186842A CN201811210681.9A CN201811210681A CN109186842A CN 109186842 A CN109186842 A CN 109186842A CN 201811210681 A CN201811210681 A CN 201811210681A CN 109186842 A CN109186842 A CN 109186842A
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- signal
- magnetoelasticity
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/04—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring tension in flexible members, e.g. ropes, cables, wires, threads, belts or bands
- G01L5/10—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring tension in flexible members, e.g. ropes, cables, wires, threads, belts or bands using electrical means
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- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The present invention relates to a kind of cable method for measuring stress based on magnetoelasticity, belongs to cable stress measurement technical field.Including step S1: generating pumping signal；S2: input signal to excitation coil；S3: acquiring the signal of receiving coil, enables the signal of collected receiving coil for acquisition signal；S4: acquisition signal is filtered, filtering signal is obtained, S5: taking wirerope under multiple and different rope force value, the voltage max in filtering signal, by voltage max be ordinate and corresponding rope force value is that abscissa carries out linear function fitting, functional relation are as follows:；Wherein v is voltage max,It is stress intensity,p 1 It is slope,p 2 It is y intercept；It is acquired after fittingp 1 Withp 2 , utilize the parameter acquiredp 1 Withp 2 Constructor relational expression；S6: utilizing functional relation, in the case where measuring voltage max, calculates and obtains rope force value.
Description
Technical field
The present invention relates to cable stress measurement technical field more particularly to a kind of cable stress based on magnetoelasticity
Measurement method.
Background technique
Cable is a kind of widely used component of load facility, and one of the critical component as load-bearing,
Working condition, the size to be met with stresses will affect the safety of entire load facility.Cable once breaks down, and will lead
It causes the load-bearing of load facility to go wrong, to bring economic loss, can also cause safety accident when serious.Therefore, to wirerope
Suo Yingli, which carries out stringent detection, to have great importance.
When by stress, the magnetized state of itself can change cable.In order to obtain in magnetized state
The stress intensity information for being included, a variety of different stress measurement modes and design are largely proposed.Wherein, almost all of
The voltage integrating meter value size that measurement method based on magnetoelasticity will use reception signal is analyzed, the method only integrated
Difference, but, measurement inaccuracy big by noise effect.
Summary of the invention
The purpose of the present invention is to provide a kind of cable method for measuring stress based on magnetoelasticity, improves rope force value
The accuracy of measurement, to more accurately determine the stress on cable.
Above-mentioned purpose of the invention has the technical scheme that
A kind of cable method for measuring stress based on magnetoelasticity, including step S1: pumping signal is generated；S2: input
Pumping signal is to excitation coil；S3: acquiring the signal of receiving coil, enables the signal of collected receiving coil for acquisition signal；
S4: acquisition signal is filtered, filtering signal is obtained, S5: takes wirerope under multiple and different rope force value, filtering signal
In voltage max, by voltage max be ordinate and corresponding rope force value is that abscissa carries out linear function fitting, function
Relational expression are as follows: v=p1×σ+p2；Wherein v is voltage max, and σ is stress intensity, p1It is slope, p2It is y intercept；After fitting
The p acquired1And p2, utilize the parameter p acquired1And p2Constructor relational expression；S6: functional relation is utilized, is measuring voltage most
In the case where big value, calculates and obtain rope force value.
The present invention is further arranged to: S1: pumping signal is generated, specifically, pumping signal is by signal generator and power
Amplifier generates, and pumping signal is pulse signal, and the amplitude of pumping signal is less than the safe current size of excitation coil, frequency
Rate is fixed.
The present invention is further arranged to: S2: input signal to excitation coil, specifically, pumping signal directly inputs
Into excitation coil, continues for some time to magnetized state and stablize.
The present invention is further arranged to: S3: acquiring the signal of receiving coil, enabling the signal of collected receiving coil is to adopt
Collect signal, specifically, oscillograph is connected to receiving coil end, oscillograph is adjusted to stablize is clearly observed exponentially
Signal, is acquired by the signal of function type at this time, deposits into storage equipment.
The present invention is further arranged to: S4: being filtered to acquisition signal, filtering signal is obtained, specifically, first
The signal data of acquisition is imported in MATLAB, the high-frequency cacophony in acquisition signal is filtered out, design low-pass filter is filtered,
Obtain filtering signal:
Fs=1/10∧(-6)；
N=length (y)；
B=fir1 (40, B/ (fs/2))；
Y_after_fir=filter (b, 1, y)；
Wherein, fs is sample rate, and b is filter bandwidht, and n is number of sampling points, and y is filtering front signal, and b is filter
Construction, fir1 is filter function in MATLAB, and y_after_fir is filtered signal, and filter is that letter is filtered in MATLAB
Number.
The present invention is further arranged to: obtaining the method for the voltage max in filtering signal specifically, data are utilized
MATLAB finds voltage max: m=max (y_after_fir)；Wherein, m is voltage max, and max is obtained in MATLAB
The function of data maximums in matrix.
The present invention is further arranged to: if exponential function type signal adjacent in acquisition signal has overlapping, needing to drop
The frequency of low pumping signal.
In conclusion advantageous effects of the invention are as follows: the present invention is based on the cable stress measurement sides of magnetoelasticity
Method generates pumping signal by using signal generator, then to excitation coil input signal, in the oscillography of receiving coil end
Device carries out signal observation, and voltage signal magnitude has moment to become larger to illustrate that there is an induced voltage generation in the part, therefore acquires signal and have
Then this segment signal become zero from maximum value carries out signal filtering using MATLAB, to treated, signal is done further
Analysis, extract voltage max and rope force value and be fitted, the linear relationship of voltage max and rope force value is found, with maximum
Voltage value is that index judges cable stress represented under different maximum voltage values.Meanwhile the present invention utilizes voltage max
As new index, the accuracy of rope force measurement is also further improved, to more accurately determine answering on cable
Power.
Detailed description of the invention
Fig. 1 is the connection schematic diagram of experiment equipment in collection process；
Fig. 2 is sensor cross-section figure；
Fig. 3 is the waveform diagram of induced voltage signal；
Fig. 4 is the function relation figure of stress and voltage max, integrated value under 9V voltage；
Fig. 5 is the function relation figure of stress and voltage max, integrated value under 10V voltage；
Fig. 6 is the function relation figure of stress and voltage max, integrated value under 11V voltage.
Specific embodiment
Below in conjunction with attached drawing, the technical solution of the embodiment of the present invention is described.
Essence of the invention is a kind of particular kind of relationship found between stress and voltage, thus more acurrate by observation voltage
Ground monitors the stress on cable.The present invention finds stress and voltage max using voltage max as new index
Linear relationship judges cable stress represented under different voltages as index using voltage max, further improves stress
The accuracy of measurement.
As shown in Figure 1, being the connection schematic diagram of experiment equipment in collection process.
As shown in Fig. 2, being sensor cross-section figure.
Pumping signal is generated by using signal generator, then to excitation coil input signal, at receiving coil end
Signal observation is carried out with oscillograph, and voltage signal magnitude has moment to become larger to illustrate that there is induced voltage generation in the part, therefore acquires
Signal has this segment signal become zero from maximum value, then carries out signal filtering using MATLAB, signal is done to treated
Further analysis, extracts voltage max and rope force value is fitted, and finds the linear relationship of voltage max and rope force value,
Cable stress represented under different maximum voltage values is judged as index using maximum voltage value.
In the present embodiment, the cable method for measuring stress based on magnetoelasticity the following steps are included:
S1: pumping signal is generated；
Continuously pumping signal is generated using signal generator and power amplifier, it is solid which should be frequency
When measurement, pumping signal is directly inputted into excitation coil for fixed pulse signal.The waveform of pumping signal such as Fig. 3 institute
Show.
S2: input signal to excitation coil；
Continuously pumping signal is generated using signal generator and power amplifier, it is solid which should be frequency
When measurement, pumping signal is directly inputted into excitation coil for fixed pulse signal.
S3: the signal of receiving coil is acquired；
After a period of time, oscillograph is connected to receiving coil end, oscillograph is adjusted to stablize and is clearly observed
To the signal of exponentially function type, the process of oscillograph modulation are as follows: the sample frequency knob for first adjusting oscillograph makes on display
Waveform can be stable display.Adjusting " voltage/lattice " and " time/lattice " knob again makes entire waveform occupy the 2/3 of screen.This
When signal is acquired, deposit to storage equipment in；Enable the signal of collected receiving coil for acquisition signal.
S4: acquisition signal is filtered；
The signal data of acquisition is imported in MATLAB first, the high-frequency cacophony in acquisition signal is filtered out, designs low pass filtered
Wave device is filtered, and obtains filtering signal:
Fs=1/10∧(-6)；
N=length (y)；
B=fir1 (40, B/ (fs/2))；
Y_after_fir=filter (b, 1, y)；
Function formula:
Fir1: returning to the 40 rank FIR low pass filter coefficient vectors that 6dB cutoff frequency is B/ (fs/2), and default, which is selected, breathes out
Bright window.
Filter:y_after_fir (n)=b (1) * y (n)+b (2) * y (n-1)+...+b (nb+1) * y (n-na)-y_
after_fir(n-1)-...-y_after_fir(n-na)
Wherein, n-1 is filter order, na be after to feedback filter order, nb is the filter order of feed-forward
Number.
Wherein, fs is sample rate, and b is filter bandwidht, and n is number of sampling points, and y is filtering front signal, and b is filter
Construction, fir1 is filter function in MATLAB, and y_after_fir is filtered signal, and filter is that letter is filtered in MATLAB
Number.
S5: the linear relationship of rope force value and maximum voltage value is generated；
The corresponding size being demonstrated by synchronization stress of voltage max, to voltage max and corresponding stress intensity into
Row fitting, obtains the functional relation of voltage max and stress, using the cftool in MATLAB, is with voltage max
Ordinate, rope force value size are that abscissa carries out linear function fitting, and wherein functional relation is as follows:
V=p1×σ+p2
Wherein v is voltage max, and σ is stress intensity, p1It is slope, p2It is y intercept；The p acquired after fitting1And p2,
Utilize the parameter p acquired1And p2Constructor relational expression.For the cable wire of different model, since the difference of material, size is led
Cause magnetization degree inconsistent, obtained p1And p2It will be different.
S6: utilizing functional relation, in the case where measuring voltage max, calculates and obtains rope force value.
In this case study on implementation, by taking the experimental data that certain equipment company provides as an example, the relevant information of testing stand is as follows:
The experimental bench is by 10 tons of cranes, signal generator, oscillograph, self-control cable tension sensor, 0.35 ton of pulling force pair
As, 1.149 tons of pulling force objects, 3.63 tons of pulling force objects, specification be 15.17mm wirerope form.
This experiment is using ac square wave signal as pumping signal, because ac square wave signal can not only provide time domain periodic
The voltage of variation, and it is able to satisfy the requirement of wirerope magnetic history.Different excitation voltage amplitudes will lead to different magnetization
Intensity, to provide different transducer sensitivities.By the calculating to self-control sensor specification, selected driving voltage is respectively
9V, 10V and 11V.Furthermore, it is contemplated that the accuracy of next digital filtering process, selects 3Hz as driving voltage frequency.
By suspension different weight weight stretch wirerope, measuring steel wire rope stop swinging after induced voltage.Suo Li is tested every
Repeat three times under a rope force value and each driving voltage, the end value of each condition is the average value of three test values.Its
Measurement result such as table 1:
Above-mentioned data are fitted with the present invention, and are compared to traditional voltage integrating meter value.Table 2, table 3
Under the driving voltage for respectively showing 9V, 10V and 11V with table 4 and Fig. 4, Fig. 5, Fig. 6, rope force value and voltage max and electricity
Relationship between hematocrit score value.The method that voltage integrating meter value seeks force value are as follows: MATLAB seeks voltage integrating meter value formula:
S=sum (y_after_fir)
Wherein s is integrated voltage value, and sum () is summing function:
Wherein, n is element number in matrix, and yi is i-th of element, then seeks the linear letter of voltage integrating meter value Yu rope force value
Number relationship.
Under the driving voltage of table 2:9V, rope force value fitting result error analysis.
Under the driving voltage of table 3:10V, rope force value fitting result error analysis.
Under the driving voltage of table 4:11V, rope force value fitting result error analysis.
Wherein, p1: coefficient of first order；
P2: constant；
SSE: being the quadratic sum due to caused by the match value and measurement error of rope force value；Calculation formula are as follows:
R-square: the match value of rope force value and the coefficient of determination of measured value；Calculation formula are as follows:
RMSE: the match value of rope force value and the root-mean-square error of measured value；Calculation formula are as follows:
Wherein, n is the quantity of data in array, yiFor i data measurement of voltage regulation,It is quasi- for i data of voltage regulation
Conjunction value.For the average value of voltage measuring value.
By table 2, table 3 and table 4 and Fig. 4, Fig. 5, Fig. 6 it is found that under three kinds of driving voltages, SSE and RMSE value are closer
In 0, R-square closer to 1, linear relationship is better.Comprehensively consider three statistical parameters, voltage max and rope force value be in compared with
Good linear relationship, and induced voltage and the integral of rope force value are obviously unsatisfactory for linear relationship.The present invention is fitted in linear relationship
Property aspect be substantially better than traditional method, and there is stronger adaptability.The present invention is applied to cable stress measurement, is answering
Also have the advantages that certain in terms of power measurement accuracy, also embody the advantage for simply monitoring Suo Li size using voltage max.
Although the illustrative specific embodiment of the present invention is described above, in order to the technology of the art
Personnel understand the present invention, it should be apparent that the present invention is not limited to the range of specific embodiment, to the common skill of the art
For art personnel, if various change the attached claims limit and determine the spirit and scope of the present invention in, these
Variation is it will be apparent that all utilize the innovation and creation of present inventive concept in the column of protection.
Claims (7)
1. a kind of cable method for measuring stress based on magnetoelasticity, including step S1: generating pumping signal；S2: input swashs
Signal is encouraged to excitation coil；S3: acquiring the signal of receiving coil, enables the signal of collected receiving coil for acquisition signal；S4:
Acquisition signal is filtered, filtering signal is obtained, which is characterized in that S5: taking wirerope under multiple and different rope force value,
Voltage max in filtering signal, by voltage max be ordinate and corresponding rope force value is that abscissa progress linear function is intended
It closes, functional relation are as follows: v=p1×σ+p2；Wherein v is voltage max, and σ is stress intensity, p1It is slope, p2It is that y-axis is cut
Away from；The p acquired after fitting1And p2, utilize the parameter p acquired1And p2Constructor relational expression；S6: utilizing functional relation,
In the case where measuring voltage max, calculates and obtain rope force value.
2. a kind of cable method for measuring stress based on magnetoelasticity according to claim 1, which is characterized in that S1:
Pumping signal is generated, specifically, pumping signal is generated by signal generator and power amplifier, pumping signal is alternating-current pulse letter
Number, safe current size, the frequency that the amplitude of pumping signal is less than excitation coil are fixed.
3. a kind of cable method for measuring stress based on magnetoelasticity according to claim 1, which is characterized in that S2:
Input signal continues for some time specifically, pumping signal is directly inputted into excitation coil to magnetization to excitation coil
It is in stable condition.
4. a kind of cable method for measuring stress based on magnetoelasticity according to claim 1, which is characterized in that S3:
The signal for acquiring receiving coil enables the signal of collected receiving coil for acquisition signal, connects specifically, oscillograph is connected to
Coil-end is received, oscillograph is adjusted to stablize the signal for being clearly observed exponentially function type, at this time adopts signal
Collection is deposited into storage equipment.
5. a kind of cable method for measuring stress based on magnetoelasticity according to claim 1, which is characterized in that S4:
Acquisition signal is filtered, filtering signal is obtained, specifically, first import the signal data of acquisition in MATLAB,
The high-frequency cacophony in acquisition signal is filtered out, design low-pass filter is filtered, obtain filtering signal:
Fs=1/10 ∧ (- 6)；
N=length (y)；
B=fir1 (40, B/ (fs/2))；
Y_after_fir=filter (b, 1, y)；
Wherein, fs is sample rate, and b is filter bandwidht, and n is number of sampling points, and y is filtering front signal, and b is filter construction,
Fir1 is filter function in MATLAB, and y_after_fir is filtered signal, and filter is filter function in MATLAB.
6. a kind of cable method for measuring stress based on magnetoelasticity according to claim 5, which is characterized in that obtain
The method of voltage max in filtering signal is specifically, find voltage max: m=max (y_ using MATLAB for data
after_fir)；Wherein, m is voltage max, and max is the function that data maximums in matrix are obtained in MATLAB.
7. a kind of cable method for measuring stress based on magnetoelasticity according to claim 1, which is characterized in that if
Adjacent exponential function type signal has overlapping in acquisition signal, then needs to reduce the frequency of pumping signal.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110057872A (en) * | 2019-05-14 | 2019-07-26 | 重庆交通大学 | A kind of cable fracture of wire monitoring method based on detection self inductance effect inductance |
| CN110596233A (en) * | 2019-08-27 | 2019-12-20 | 电子科技大学 | Steel wire rope magnetic flux leakage imaging real-time processing method under continuous sampling |
| CN111676981A (en) * | 2020-06-05 | 2020-09-18 | 浙江新中源建设有限公司 | Foundation pit supporting structure and construction method thereof |
| CN115326267A (en) * | 2022-10-17 | 2022-11-11 | 山东省地质矿产勘查开发局第五地质大队（山东省第五地质矿产勘查院） | Logging cable tension measurement alarm instrument and use method thereof |
| CN115655550A (en) * | 2022-10-28 | 2023-01-31 | 思特尔智能检测系统(苏州)有限公司 | Sensor layout method for testing stress state of iron-based plate |
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| CN103557973A (en) * | 2013-11-20 | 2014-02-05 | 重庆交通大学 | In-service structure prestress in-situ detecting system and method |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110057872A (en) * | 2019-05-14 | 2019-07-26 | 重庆交通大学 | A kind of cable fracture of wire monitoring method based on detection self inductance effect inductance |
| CN110596233A (en) * | 2019-08-27 | 2019-12-20 | 电子科技大学 | Steel wire rope magnetic flux leakage imaging real-time processing method under continuous sampling |
| CN110596233B (en) * | 2019-08-27 | 2022-11-22 | 电子科技大学 | Steel wire rope magnetic flux leakage imaging real-time processing method under continuous sampling |
| CN111676981A (en) * | 2020-06-05 | 2020-09-18 | 浙江新中源建设有限公司 | Foundation pit supporting structure and construction method thereof |
| CN115326267A (en) * | 2022-10-17 | 2022-11-11 | 山东省地质矿产勘查开发局第五地质大队（山东省第五地质矿产勘查院） | Logging cable tension measurement alarm instrument and use method thereof |
| CN115326267B (en) * | 2022-10-17 | 2023-01-24 | 山东省地质矿产勘查开发局第五地质大队（山东省第五地质矿产勘查院） | Logging cable tension measurement alarm instrument and use method thereof |
| CN115655550A (en) * | 2022-10-28 | 2023-01-31 | 思特尔智能检测系统(苏州)有限公司 | Sensor layout method for testing stress state of iron-based plate |
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Application publication date: 20190111 |