CN109282941A - A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor - Google Patents
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor Download PDFInfo
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- CN109282941A CN109282941A CN201811399260.5A CN201811399260A CN109282941A CN 109282941 A CN109282941 A CN 109282941A CN 201811399260 A CN201811399260 A CN 201811399260A CN 109282941 A CN109282941 A CN 109282941A
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- monoblock type
- hopkinson bar
- pvdf sensor
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
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- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor, the invention belongs to PVDF sensor test calibration technical fields, and in particular to a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor.The present invention be in order to solve it is existing one PVDF sensor of calibration is only capable of using each shock pulse of split hopkinson bar, demarcating simultaneously such as multisensor will appear shock pulse Signal averaging non-uniform phenomenon and the short problem of calibrated span.A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor is made of monoblock type Hopkinson bar, PVDF sensor test suite, signal acquiring system；The monoblock type Hopkinson bar is an integral structure；PVDF sensor test suite is threadably secured at the sample to be tested of monoblock type Hopkinson bar；The configuration of the present invention is simple may be implemented multiple batches of PVDF sample while demarcate.
Description
Technical field
The invention belongs to PVDF sensor test calibration technical fields, and in particular to one kind is based on monoblock type Hopkinson bar
The shock measuring system of PVDF sensor.
Background technique
PVDF (gathering inclined tetrafluoroethene thin-film material) is a kind of novel high polymer piezoelectric film material, has preferable piezoelectricity
Characteristic, the PVDF sensor made of PVDF thin film have the spies such as flexible, frequency response is wide, noise signal is small, impedance matching is good
Point has a wide range of applications in explosion mechanics, ballistics etc. are conducive to.Since the common piezoelectricity of test blast impulse pressure passes
Sensor is difficult to be monitored the impact force, and the monitoring of PVDF sensor is up to 20Gpa impact force, while testing range is greater than
0.3Gpa or more has the good linearity, so being widely used in the pressure monitoring environment of blast impulse.
The problems such as uniformity of dynamic piezoelectric characteristic, frequency response, mechanical characteristic and material for PVDF itself, is current
Study less, the calibration of the piezoelectric modulus of PVDF is confined to surge and is demarcated, rushed using air gun system greater than 0.3Gpa
It hits pressure and is demarcated less than 0.3Gpa using split hopkinson bar, and be less than using split hopkinson bar
When 100Mpa Experimental Calibration, bullet velocity is easy to appear false triggering state close to minimum triggering speed, and pulse signal can not pass to
Sample surfaces, so that calibration failure；One PVDF of calibration is only capable of using each shock pulse of split hopkinson bar simultaneously to pass
Sensor, demarcating simultaneously such as multisensor will appear pulse signal superposition non-uniform phenomenon.
Summary of the invention
The present invention is to solve the existing use each shock pulse of split hopkinson bar and be only capable of one PVDF of calibration
Sensor, demarcating simultaneously such as multisensor will appear pulse signal superposition non-uniform phenomenon and the short problem of calibrated span, and
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor is provided.
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor of the present invention is by monoblock type Hope's gold
Gloomy bar, PVDF sensor test suite, signal acquiring system composition；The monoblock type Hopkinson bar is an integral structure；Institute
PVDF sensor test suite is stated to be threadably secured at the sample to be tested of monoblock type Hopkinson bar；The PVDF sensor
Test suite is made of fixture cover, fixture base, fixture fixed screw and several PVDF sensors, the fixture cover and
Fixture base is in concave-convex tight fit and is screwed by fixture fixed screw, several described PVDF sensor clampings are in fixture
Between upper cover and fixture base；The signal acquiring system is made of oscillograph and charge amplifier；The single PVDF sensing
Device is circumscribed with p-wire, and one end of the p-wire is connected on the positive and negative anodes of PVDF sensor, the other end of the p-wire
It is connected on the positive and negative anodes of charge amplifier；The signal receiving end phase of the signal output end of the charge amplifier and oscillograph
Even.
Beneficial effects of the present invention:
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor of the present invention is using whole
Formula Hopkinson bar completes PVDF transducer calibration, and shock pulse can be evenly applied to wait mark by PVDF sensor test suite
Determine sensor surface, and can realize the calibration of more sensors with a shock pulse；PVDF sensor test suite exists simultaneously
In impact test, mass block can be used as, adjust the magnitude of shock pulse, increase the range of calibration；The test macro has
Easy to operate, calibration range is greatly, calculating is succinct, it can be achieved that one impulse pulse signal completes the characteristics of multisensor is demarcated.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of shock measuring system based on monoblock type Hopkinson bar PVDF sensor；
Fig. 2 is the structural schematic diagram of PVDF sensor test suite；
Fig. 3 is the cross section view of Fig. 2；
Fig. 4 is the side view of fixture base；
Fig. 5 is the side view of fixture cover.
Specific embodiment
Specific embodiment 1: illustrating in conjunction with FIG. 1 to FIG. 5, present embodiment one kind is based on monoblock type Hopkinson bar
The shock measuring system of PVDF sensor is by monoblock type Hopkinson bar 1, PVDF sensor test suite 2, signal acquiring system 3
Composition；The monoblock type Hopkinson bar 1 is an integral structure；The PVDF sensor test suite 2 be threadably secured in
At the sample to be tested of monoblock type Hopkinson bar 1；The PVDF sensor test suite 2 by fixture cover 21, fixture base 22,
Fixture fixed screw 23 and several PVDF sensors 24 form, and the fixture cover 21 and fixture base 22 are in concave-convex tight fit
And be screwed by fixture fixed screw 23, several described 24 clampings of PVDF sensor are in fixture cover 21 and fixture base
Between 22；The signal acquiring system 3 is made of oscillograph and charge amplifier；The single PVDF sensor 24 is circumscribed with survey
Line is tried, one end of the p-wire is connected on the positive and negative anodes of PVDF sensor 24, and the other end of the p-wire is connected to electricity
On the positive and negative anodes of lotus amplifier；The signal output end of the charge amplifier is connected with the signal receiving end of oscillograph.
Present embodiment is uniform by the shock pulse that PVDF sensor test suite issues monoblock type Hopkinson bar
It is applied to PVDF sensor surface, using the piezoelectric property of PVDF sensor, corresponding electric signal is converted by shock pulse, by suddenly
The voltage value of the PVDF sensor output for mechanics value and the signal acquiring system acquisition that Pu Jinsen bar Plays sensor measures,
PVDF sensor piezoelectric modulus calibration curve to be calibrated is established by calculating.
The contact surface surface of the fixed sensor of present embodiment is smooth, flatness is high.
PVDF sensor clamping is between fixture cover and fixture base without relative displacement described in present embodiment.
PVDF sensor test suite can be used as mass block in present embodiment, by controlling PVDF sensor test group
The material of part, volume, shape control the weight of mass block, and then control shock pulse size.
The center of PVDF sensor test suite is set at the sample to be tested of present embodiment monoblock type Hopkinson bar 1
Position.
Specific embodiment 2: the present embodiment is different from the first embodiment in that: the PVDF sensor 24 with
The contact surface of fixture cover 21 and fixture base 22 coats vaseline.Other are same as the specific embodiment one.
The transmitting of shock pulse signal can be enhanced in present embodiment.
Specific embodiment 3: the present embodiment is different from the first and the second embodiment in that: the monoblock type Hope
Standard mechanics value measured by standard transducer in the gloomy bar 1 of gold is acceleration.Other are the same as one or two specific embodiments.
Specific embodiment 4: unlike one of present embodiment and specific embodiment one to three: on the fixture
Lid 21 and fixture base 22 are regular polygon structure, several described PVDF sensors 24 are evenly arranged on each side.Other with
One of specific embodiment one to three is identical.
The other end of the p-wire of several PVDF sensors of present embodiment can connect in the same charge amplifier
It also can connect on the positive and negative anodes in different channels on the positive and negative anodes of multiple independent charge amplifiers；Charge amplifier can be with
One oscillograph difference channel or the cooperation of multiple oscillographs.
Specific embodiment 5: unlike one of present embodiment and specific embodiment one to four: single described
The both ends of PVDF sensor 24 are parallel with capacitor or resistance.Other are identical as one of specific embodiment one to four.
Specific embodiment 6: unlike one of present embodiment and specific embodiment one to five: the capacitor
Capacitance is 1 μ F, and the resistance value of resistance is 10 Ω.Other are identical as one of specific embodiment one to five.
Specific embodiment 6: unlike one of present embodiment and specific embodiment one to five: one kind is based on whole
The application method of the shock measuring system of body formula Hopkinson bar PVDF sensor specifically sequentially includes the following steps: opening monoblock type
The gas valve of Hopkinson bar 1 controls the size of the pulse signal acceleration value of monoblock type Hopkinson bar 1, punching by PC
After hitting, the acceleration value that record 1 Plays sensor of monoblock type Hopkinson bar is shown, and obtain oscillograph trigger recording
Voltage value, the pressure calibration curve of PVDF sensor is established by relevant calculation；Pass through fixture cover 21 and fixture base 22
Quality acceleration figure is converted into force value；Then it is realized by changing the quality of fixture cover 21 and fixture base 22 to impact
The secondary control of pulse signal size.Other are identical as one of specific embodiment one to five.
The size needs of the pulse signal acceleration value of present embodiment monoblock type Hopkinson bar 1 are required according to calibration point
It is adjusted.
Specific embodiment 7: unlike one of present embodiment and specific embodiment one to six: the oscillograph
Amplification factor be 100 times.Other are identical as one of specific embodiment one to six.
Beneficial effects of the present invention are verified using following embodiment:
Embodiment one: a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor is by monoblock type Hope
The gloomy bar 1 of gold, PVDF sensor test suite 2, signal acquiring system 3 form；The monoblock type Hopkinson bar 1 is integral type knot
Structure；The PVDF sensor test suite 2 is threadably secured at the sample to be tested of monoblock type Hopkinson bar 1；It is described
PVDF sensor test suite 2 is by fixture cover 21, fixture base 22, fixture fixed screw 23 and several PVDF sensors 24
Composition, the fixture cover 21 and fixture base 22 are in concave-convex tight fit and are screwed by fixture fixed screw 23, described
Several 24 clampings of PVDF sensor are between fixture cover 21 and fixture base 22；The signal acquiring system 3 is by oscillograph
It is formed with charge amplifier；The single PVDF sensor 24 is circumscribed with p-wire, and one end of the p-wire is connected to PVDF
On the positive and negative anodes of sensor 24, the other end of the p-wire is connected on the positive and negative anodes of charge amplifier；The charge amplification
The signal output end of device is connected with the signal receiving end of oscillograph；The PVDF sensor 24 and fixture cover 21 and fixture base
22 contact surface coats vaseline；The fixture cover 21 and fixture base 22 are regular hexagon structure, six PVDF sensings
Device 24 is evenly arranged on six sides；The application method of the shock measuring system based on monoblock type Hopkinson bar PVDF sensor
The gas valve for opening monoblock type Hopkinson bar 1 is specifically sequentially included the following steps:, monoblock type Hopkinson bar is controlled by PC
The size of 1 pulse signal acceleration value, after impact, record 1 Plays sensor of monoblock type Hopkinson bar is shown
Acceleration value, and the voltage value of oscillograph trigger recording is obtained, the pressure calibration for establishing PVDF sensor by relevant calculation is bent
Line；Acceleration figure is converted into force value by the quality of fixture cover 21 and fixture base 22；Then by changing fixture cover 21
The secondary control to shock pulse signal magnitude is realized with the quality of fixture base 22.
The size of the pulse signal acceleration value of the present embodiment monoblock type Hopkinson bar need to be required according to calibration point into
Row is adjusted.The amplification factor of the oscillograph is 100 times.
A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor uses monoblock type Hope
The gloomy bar of gold completes PVDF transducer calibration, and shock pulse can be evenly applied to sensing to be calibrated by PVDF sensor test suite
Device surface, and the calibration of more sensors can be realized with a shock pulse；PVDF sensor test suite is tried in impact simultaneously
In testing, mass block can be used as, adjust the magnitude of shock pulse, increase the range of calibration；The test macro has operation letter
List, calibration range are big, calculate succinct, it can be achieved that one impulse pulse signal completes the characteristics of multisensor is demarcated.
Claims (7)
1. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor, it is characterised in that suddenly based on monoblock type
The shock measuring system of Pu Jinsen bar PVDF sensor by monoblock type Hopkinson bar (1), PVDF sensor test suite (2),
Signal acquiring system (3) composition；The monoblock type Hopkinson bar (1) is an integral structure；The PVDF sensor test group
Part (2) is threadably secured at the sample to be tested of monoblock type Hopkinson bar (1)；The PVDF sensor test suite (2)
It is made of fixture cover (21), fixture base (22), fixture fixed screw (23) and several PVDF sensors (24), the folder
Tool upper cover (21) and fixture base (22) are in concave-convex tight fit and pass through fixture fixed screw (23) and be screwed, it is described several
PVDF sensor (24) clamping is between fixture cover (21) and fixture base (22)；The signal acquiring system (3) is by oscillography
Device and charge amplifier composition；The single PVDF sensor (24) is circumscribed with p-wire, and one end of the p-wire is connected to
On the positive and negative anodes of PVDF sensor (24), the other end of the p-wire is connected on the positive and negative anodes of charge amplifier；The electricity
The signal output end of lotus amplifier is connected with the signal receiving end of oscillograph.
2. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 1,
It is characterized in that the contact surface coating vaseline of the PVDF sensor (24) and fixture cover (21) and fixture base (22).
3. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 1,
It is characterized in that standard mechanics value measured by the standard transducer in the monoblock type Hopkinson bar (1) is acceleration.
4. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 1,
It is characterized in that the fixture cover (21) and fixture base (22) are regular polygon structure, several described PVDF sensors
(24) it is evenly arranged on each side.
5. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 4,
It is characterized in that the both ends of the single PVDF sensor (24) are parallel with capacitor or resistance.
6. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 5,
The capacitance for being characterized in that the capacitor is 1 μ F, and the resistance value of resistance is 10 Ω.
7. a kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor according to claim 1,
It is characterized in that the application method of the shock measuring system based on monoblock type Hopkinson bar PVDF sensor specifically according to the following steps
It carries out: opening the gas valve of monoblock type Hopkinson bar (1), believed by the pulse of PC control monoblock type Hopkinson bar (1)
The size of number acceleration value, after impact, acceleration that record monoblock type Hopkinson bar (1) Plays sensor is shown
Value, and the voltage value of oscillograph trigger recording is obtained, the pressure calibration curve of PVDF sensor is established by relevant calculation；Pass through
Acceleration figure is converted to force value by the quality of fixture cover (21) and fixture base (22)；Then by change fixture cover (21) and
The quality of fixture base (22) realizes the secondary control to shock pulse signal magnitude.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811399260.5A CN109282941A (en) | 2018-11-22 | 2018-11-22 | A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811399260.5A CN109282941A (en) | 2018-11-22 | 2018-11-22 | A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor |
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| CN109282941A true CN109282941A (en) | 2019-01-29 |
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| CN201811399260.5A Pending CN109282941A (en) | 2018-11-22 | 2018-11-22 | A kind of shock measuring system based on monoblock type Hopkinson bar PVDF sensor |
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Cited By (3)
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| CN110082029A (en) * | 2019-04-19 | 2019-08-02 | 天津大学 | A kind of PVDF piezoelectric film sensor dynamic characteristics scaling method |
| CN110672241A (en) * | 2019-09-02 | 2020-01-10 | 南京理工大学 | Shock wave pressure sensor |
| CN113155338A (en) * | 2021-04-21 | 2021-07-23 | 北京理工大学 | System and method for testing time constant of underwater explosion near-field shock wave |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110082029A (en) * | 2019-04-19 | 2019-08-02 | 天津大学 | A kind of PVDF piezoelectric film sensor dynamic characteristics scaling method |
| CN110672241A (en) * | 2019-09-02 | 2020-01-10 | 南京理工大学 | Shock wave pressure sensor |
| CN113155338A (en) * | 2021-04-21 | 2021-07-23 | 北京理工大学 | System and method for testing time constant of underwater explosion near-field shock wave |
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