CN105527047B - One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer - Google Patents
One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer Download PDFInfo
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- CN105527047B CN105527047B CN201511020998.2A CN201511020998A CN105527047B CN 105527047 B CN105527047 B CN 105527047B CN 201511020998 A CN201511020998 A CN 201511020998A CN 105527047 B CN105527047 B CN 105527047B
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- mems acceleration
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- cable force
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- 230000004907 flux Effects 0.000 title claims abstract description 53
- 230000001133 acceleration Effects 0.000 title claims abstract description 41
- 238000001514 detection method Methods 0.000 claims abstract description 16
- 230000005284 excitation Effects 0.000 claims abstract description 13
- 230000006698 induction Effects 0.000 claims abstract description 13
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 6
- 239000010959 steel Substances 0.000 claims abstract description 6
- 239000003990 capacitor Substances 0.000 claims description 11
- 238000012937 correction Methods 0.000 claims description 4
- 230000032683 aging Effects 0.000 abstract description 4
- 238000012544 monitoring process Methods 0.000 abstract description 4
- 238000012545 processing Methods 0.000 abstract description 2
- 238000004519 manufacturing process Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 description 13
- 238000005259 measurement Methods 0.000 description 10
- 238000005070 sampling Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 230000035882 stress Effects 0.000 description 3
- 238000005553 drilling Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000003483 aging Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000007716 flux method Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- 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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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Bridges Or Land Bridges (AREA)
Abstract
The present invention relates to one kind to be based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, it includes MEMS acceleration transducer, excitation coil, induction coil, frequency overlapped-resistable filter, microcontroller, data disaply moudle etc..After the vibration signal that external drive suffered by bridge cable generates is filtered out aliasing signal by frequency overlapped-resistable filter by MEMS acceleration transducer, digital signal is converted into using analog-digital converter, FFT operation finally is carried out by microcontroller, finally obtains the characteristic frequency value of bridge steel cable vibration.The purpose is to for the bridge cable force detection device that detect currently based on the magnetic flux data wander caused by the aging of internal electronic component due to need to carry out field calibration, use cost height and data processing difficulty is big the problems such as.One kind of proposition has structure simple, manufacture feature magnetic flux cable force detecting device easy to use, it only needs a MEMS acceleration transducer built in inside magnetic flux transducer, it can solve the problems, such as the current maximum time drift of magnetic flux cable force detecting device, monitoring cost is reduced, and improves the validity and reliability of monitoring data.
Description
Technical field
The invention belongs to civil engineering structure security detection equipment fields, are passed more particularly to one kind based on MEMS acceleration
The modified magnetic flux cable force detecting device of sensor.
Background technique
The Suo Li size of bridge cable directly decides the work shape of the guy systems bridge such as cable-stayed bridge, suspension bridge, arch bridge
State, the variation of Suo Li are the important symbols measured zipper system bridge cable structure and whether be in normal operating condition.Therefore, it adopts
Carrying out detection to bridge cable force with accurate method is to guarantee the necessary means of bridge smooth construction and safe operation.
Currently, the detection of domestic bridge cable force is usually to use following several methods: oil pressure gauge method, pressure sensor are surveyed
Fixed, vibratory drilling method (frequency method) etc..But since oil pressure gauge method is there are the easy deviation of pointer, pointer shake is big when high pressure, and reading is artificial
The disadvantages of error is big；The problems such as determination of pressure sensor method dynamic response is poor, and the service life is short, expensive；Vibratory drilling method (frequency method)
Reliability depend on the installation site of vibration pickup, the problems such as can not achieve round-the-clock detection.
But in recent years for bridge cable force detection occur using magnetic flux method as the new method of representative, and have compared with
High future in engineering applications.The principle of bridge cable force magnetic flux quantity measuring method is the magnetoelastic effect based on ferrimagnet, i.e.,
When the external mechanical load that ferrimagnet is born changes, the internal intensity of magnetization (magnetic conductivity) changes.?
In engineering practice, the magnetic conductivity variation of the component made of test ferrimagnet can be used to measure in component to answer
Power.However, being a static absolute voltage currently based on the magnetic flux that the bridge cable force detection device that magnetic flux detects measures
Value, this voltage value can be because of the agings of magnetic flux transducer Inside coil and other electronic components and over time
It can cause data wander.This, which will lead to, is needed in engineering practice to the bridge cable force detection device detected based on magnetic flux again
Carry out field calibration；Meanwhile this also leads to the difficulty that use cost increases and increases data processing.Therefore, this to be based on magnetic
Application has some limitations the bridge cable force detection device of flux detection in engineering.
Summary of the invention
Aiming at the shortcomings in the prior art, it is modified based on MEMS acceleration transducer that the object of the present invention is to provide one kind
Magnetic flux cable force detecting device.Micro-vibration occurs since bridge cable will receive the exciting of the factors such as vehicle, strong wind, this hair
It is bright to be built into the solution of the technology in magnetic flux transducer using by the acceleration transducer for being based on MEMS (micro-electromechanical technology)
Scheme.The mechanical characteristic for showing that bridge cable is current is analyzed by measurement bridge steel cable vibration frequecy characteristic, and is passed through
The characteristic corrects the data wander of magnetic flux transducer, to not only solve magnetic flux transducer Inside coil and other electricity
Data wander problem caused by the aging of sub- component also improves the stability and reliability of bridge cable force measurement.
Technical solution of the invention:
One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, including MEMS acceleration transducer
1, temperature sensor 2, excitation coil 3, induction coil 4, boost module 5, thyristor 6, high-voltage capacitor 7, bridge cable 8,
Integrator 9, low-pass filter 10, analog-digital converter 11, microcontroller 12, frequency overlapped-resistable filter 13, RS485 interface 14, data
Display module 15；
It is characterized by: the both ends of MEMS acceleration transducer 1 are connected to 13 both ends of frequency overlapped-resistable filter, it is anti-aliasing
Filter 13 is connect by RS485 interface 14 with microcontroller 12；The both ends of induction coil 4 are connect respectively at the both ends of integrator 9,
Low-pass filter 10 is connected between integrator 9 and analog-digital converter 11, analog-digital converter 11 be connected to low-pass filter 10 with
Between microcontroller 12；The both ends of excitation coil 3 and high-voltage capacitor 7 are connected in parallel on respectively on boost module 5 and thyristor 6, brilliant
Brake tube 6 is connected between high-voltage capacitor 7 and boost module 5, and data disaply moudle 15 is connected on microcontroller 12；
MEMS acceleration transducer 1 is by being mounted on formation magnetic flux Suo Li on magnetic flux transducer skeleton built in pcb board
Detection device, the vibration signal that MEMS acceleration transducer 1 generates external drive suffered by bridge cable pass through anti-mixed
After folded filter 13 filters out aliasing signal, it is converted into digital signal using analog-digital converter 11, finally passes through microcontroller 12
FFT operation is carried out, the characteristic frequency value of bridge steel cable vibration is finally obtained.
Wherein temperature sensor 2 is used to correct the temperature drift of magnetic flux transducer；Excitation coil 3 is to be detected to fill by Suo Li
Set the pumping signal of transmission；Low-pass filter 11 is the fixed frequency set according to the bandwidth of magnetic flux transducer output signal
Low-pass filter, for filtering out interference and noise except signal bandwidth；Frequency overlapped-resistable filter 13 is passed according to MEMS acceleration
The cable vibration frequecy characteristic of sensor output, according to sampling thheorem, setting meets the cutoff frequency of Sampling Theorem, mixed for filtering out
Folded signal；Thyristor 6 is used as electronic switch, is controlled by the logical signal of microcontroller 12.
Preferably, the direction of the MEMS acceleration transducer 1 is Z axis.
Preferably, the MEMS acceleration transducer 1 and 2 common power supply terminal of temperature sensor.
Preferably, the data disaply moudle 15 is touch screen, can show current cable force value, temperature drift value, feature
The data correction value of frequency values and magnetic flux transducer.
Preferably, the induction coil 4 is directly inserted in excitation coil 3, in engineering detecting, by bridge cable 8
It is directly anchored on induction coil 4, the induced voltage sensed is obtained bridge wirerope by 9 operation of integrator by induction coil 4
Rope magnetic conductivity because of caused by stress changes, and finally obtains the changing value of integral voltage.
Preferably, the microcontroller 12 can choose 51 series monolithics, also can choose ARM Series Controller,
The characteristic frequency value of bridge cable mainly is obtained to time-domain signal progress FFT operation, MEMS acceleration transducer is surveyed
The rope force value progress characteristic frequency obtained, which is calculated the data correction value of magnetic flux transducer and transfers data to data, to be shown
Module 15.
Relational expression between characteristic frequency value and bridge cable are as follows:
T=4ml2fr2/r
(wherein m is unit length Suo Chong, and l is that rope is long, and fr is r rank modal frequency)
By analyzing fr, and counter release current force value T, so that it may correct the current measurement force value of magnetic flux transducer.
High-voltage capacitor 7 discharges to excitation coil 3 by thyristor 6.
What it is because of vibration measurement is frequency signal, and by component aging generate time drift influenced is signal
Amplitude, therefore because of the time data wander will not occur for the rope force value measured by MEMS acceleration transducer, so the error
Data relative to magnetic flux transducer measurement have the meaning of bench-marking, can carry out to the measurement data of magnetic flux transducer
Amendment.It is described based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, it is characterised in that: induction coil 4
The induced voltage sensed is shown that bridge cable magnetic conductivity because of caused by stress changes by 9 operation of integrator, finally
Obtain the changing value of integral voltage.
The present invention has structure simple, manufactures feature easy to use, it is only necessary to one built in inside the magnetic flux transducer
A MEMS acceleration transducer, so that it may solve the problems, such as the current maximum time drift of magnetic flux cable force detecting device, reduce
Monitoring cost, and improve the validity and reliability of monitoring data.
Detailed description of the invention
Fig. 1 is magnetic flux transducer internal structure chart of the present invention；
Fig. 2 is magnetic flux acquisition principle block diagram of the present invention.
The components in the drawings are labeled as follows: 1, MEMS acceleration transducer；2, temperature sensor；3, excitation coil；4,
Induction coil；5 boost modules；6, thyristor；7, high-voltage capacitor；8, bridge cable；9, integrator；10, low-pass filter；
11, analog-digital converter；12, microcontroller；13, frequency overlapped-resistable filter；14, RS485 interface；15, data disaply moudle.
Specific embodiment
The present invention can be embodied by disclosed technology, can be carried out the present invention into one by the following examples
The description of step, however, the scope of the present invention is not limited to following embodiments.
Embodiment is as shown in Figure 2: MEMS sensor is fixed on pcb board simultaneously by the present invention first in implementation process
It is built-in to be mounted on magnetic flux transducer skeleton, since the vibration axis direction of MEMS acceleration transducer will be with bridge cable
Direction of vibration keeps vertical, so being typically chosen the direction that Z axis is MEMS acceleration transducer.Further, since MEMS acceleration
Sensor need to only power can direct voltage output signal, so the power supply of MEMS sensor can be together with temperature sensor
Power supply is to reduce power supply terminal.
After cable force detecting device is installed make as shown in Figure 2 Suo Li detection can be carried out to bridge cable.?
In engineering practice, the output cord of MEMS acceleration transducer need to only be drawn.When detection device and bridge cable are pacified
After the completion of dress, Suo Li detection can be started.Firstly, magnetic flux cable force detecting device is by boost module 5 using thyristor 6
The charging of high-voltage capacitor 7 is until setting voltage value；Then, when magnetic flux cable force detecting device microcontroller 12 receives acquisition life
After order, high-voltage capacitor 7 discharges to excitation coil 3 by the thyristor 6 connecting with excitation coil 3, while induction coil 4
Sense the induced voltage because of caused by magnetic flux change；Finally, passing through the integrating circuit inside magnetic flux cable force detecting device
And it filter filtering and improves and obtains the induction caused by the variation of corresponding magnetic conductivity under different stress conditions of bridge cable
Voltage change.
When needing to correct the data of magnetic flux cable force detecting device magnetic flux transducer measurement, firstly, it is necessary to utilize
MEMS acceleration transducer is sampled, and the data of sampling obtain after being handled by frequency overlapped-resistable filter 13 and analog-digital converter 11
The time domain data of one group of equal interval sampling；Then, and FFT operation is carried out to it by microcontroller 12 and obtains current bridge wirerope
The characteristic frequency value of Suo Zhendong；Finally, correcting magnetic flux transducer by rope force value corresponding to current signature frequency values
Inductive voltage value.For example, the bridge steel cable tension value that measurement obtains after magnetic flux cable force detecting device is installed for the first time is T0,
The characteristic frequency that MEMS acceleration transducer measures at this time is 5Hz, can be calculated current bridge by T=4ml2fr2/r formula
The pulling force of joist steel cable is T, is stored the two data as the initial value of detection device, at the beginning of general installation (T0=T).
But, it is assumed that magnetic flux cable force detecting device is detected by magnetic flux Suo Li and is filled after the use of some months
The current value of thrust of bridge wirerope cable for setting measurement is T1, and is Tn by the value of thrust that MEMS acceleration transducer measures,
At this point, can be the correction value of magnetic flux transducer by Tn-T=A, T1- (T0+A)=C, C, so as to each measurement
Value subtracts C and can be obtained absolute by value of thrust suffered by current bridge cable, is finally reached the modified technical effect of Suo Li.
The above only expresses the preferred embodiment of the present invention, and the description thereof is more specific and detailed, but can not be because
This and be interpreted as limitations on the scope of the patent of the present invention.It should be pointed out that for those of ordinary skill in the art,
Under the premise of not departing from present inventive concept, several deformations can also be made, improves and substitutes, these belong to protection of the invention
Range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.
Claims (6)
1. one kind is based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, including MEMS acceleration transducer
(1), temperature sensor (2), excitation coil (3), induction coil (4), boost module (5), thyristor (6), high-voltage capacitor
(7), bridge cable (8), integrator (9), low-pass filter (10), analog-digital converter (11), microcontroller (12), anti-aliasing
Filter (13), RS485 interface (14), data disaply moudle (15)；It is characterized by: the two of MEMS acceleration transducer (1)
End is connected on frequency overlapped-resistable filter (13), and frequency overlapped-resistable filter (13) is connected by RS485 interface and microcontroller (12)
It connects；Induction coil (4) is directly inserted in excitation coil (3), and both ends are connect respectively on integrator (9), and integrator successively connects
Connect low-pass filter (10), analog-digital converter (11) and microcontroller (12), bridge cable force detection when bridge cable (8) with
Induction coil (4) is fixedly connected；The MEMS acceleration transducer (1) is built on magnetic flux transducer skeleton by pcb board,
And the vibration signal for generating external drive suffered by bridge cable, successively through frequency overlapped-resistable filter, analog-digital converter and micro-control
Device processed obtains the characteristic frequency value of bridge steel cable vibration；The both ends of the excitation coil (3) and high-voltage capacitor (7) difference
It being connected in parallel on boost module (5) and thyristor (6), thyristor (6) is connected between high-voltage capacitor (7) and boost module (5),
High-voltage capacitor (7) discharges to excitation coil (3) by thyristor (6).
2. according to claim 1 be based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, feature
Be: the vibration axis direction of the MEMS acceleration transducer (1) is vertical with the holding of the direction of vibration of bridge cable, and MEMS adds
The vibration axis direction of velocity sensor (1) is Z axis.
3. according to claim 1 or 2 be based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, spy
Sign is: the MEMS acceleration transducer (1) and temperature sensor (2) common power supply terminal.
4. according to claim 1 be based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, feature
Be: microcontroller (12) is 51 series monolithics or ARM Series Controller.
5. according to claim 1 be based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer, feature
Be: microcontroller (12) carries out FFT operation to time-domain signal and obtains the characteristic frequency value of bridge cable, to MEMS acceleration
Rope force value measured by sensor carries out characteristic frequency and the data correction value of magnetic flux transducer is calculated, and data are transmitted
To data disaply moudle (15).
6. it is based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer according to claim 1 or 5, it is special
Sign is: data disaply moudle (15) is touch screen, and is connect with microcontroller (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511020998.2A CN105527047B (en) | 2015-12-30 | 2015-12-30 | One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511020998.2A CN105527047B (en) | 2015-12-30 | 2015-12-30 | One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer |
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| CN105527047A CN105527047A (en) | 2016-04-27 |
| CN105527047B true CN105527047B (en) | 2019-03-19 |
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| CN201511020998.2A Expired - Fee Related CN105527047B (en) | 2015-12-30 | 2015-12-30 | One kind being based on the modified magnetic flux cable force detecting device of MEMS acceleration transducer |
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Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107063545B (en) * | 2016-12-20 | 2024-02-27 | 江西飞尚科技有限公司 | Cable force motion detector based on correction FFT algorithm and algorithm thereof |
| CN106644229B (en) * | 2017-01-20 | 2022-09-20 | 华中科技大学 | In-service cable force detection device and method |
| CN109024279A (en) * | 2018-09-30 | 2018-12-18 | 柳州欧维姆机械股份有限公司 | A kind of built-in acceleration sensor drag-line |
| CN109596257B (en) * | 2018-11-15 | 2024-03-08 | 交通运输部公路科学研究所 | Force nondestructive in-situ measurement device and method |
| CN109406631B (en) * | 2018-11-28 | 2024-05-24 | 交通运输部公路科学研究所 | Parallel steel wire pulling sling detection device and method |
| CN111928890B (en) * | 2020-07-14 | 2022-04-05 | 宁波大学 | Method for measuring self-vibration frequency and cable force of inhaul cable in real time |
| CN113295317A (en) * | 2021-05-20 | 2021-08-24 | 吉林大学 | Bridge construction cable force testing method and device based on bionic principle |
| CN114878053B (en) * | 2022-06-02 | 2024-04-19 | 辽宁省交通高等专科学校 | Novel high-precision cable force device of piezoelectric type |
| CN115452204B (en) * | 2022-08-30 | 2023-05-12 | 华能广西清洁能源有限公司 | Force sensing measurement method based on inverse magnetostriction effect |
| CN116026512B (en) * | 2023-03-30 | 2023-07-04 | 江西飞尚科技有限公司 | Soxhlet calculation temperature fitting method, system, computer and readable storage medium |
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| CN1952635A (en) * | 2006-11-14 | 2007-04-25 | 重庆大学 | Differential and temperature compensating type on-line testing method and system for bridge cable force |
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| CN202757721U (en) * | 2012-04-06 | 2013-02-27 | 江西飞尚科技有限公司 | Magnetic-flux cable force detection device |
| CN103528720A (en) * | 2013-10-25 | 2014-01-22 | 交通运输部公路科学研究所 | Precise detection device and detection method for stress of invitro prestressed steel beam |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US6941824B2 (en) * | 2003-04-25 | 2005-09-13 | Delphi Technologies, Inc. | Magnetic force sensor and control circuit for same |
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|---|---|---|---|---|
| CN1952635A (en) * | 2006-11-14 | 2007-04-25 | 重庆大学 | Differential and temperature compensating type on-line testing method and system for bridge cable force |
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