CN102608346A - Electromagnetic-induction speed measurement device for underwater projectile bodies - Google Patents
Electromagnetic-induction speed measurement device for underwater projectile bodies Download PDFInfo
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- CN102608346A CN102608346A CN2012100651751A CN201210065175A CN102608346A CN 102608346 A CN102608346 A CN 102608346A CN 2012100651751 A CN2012100651751 A CN 2012100651751A CN 201210065175 A CN201210065175 A CN 201210065175A CN 102608346 A CN102608346 A CN 102608346A
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Abstract
The invention relates to an electromagnetic-induction speed measurement device for underwater projectile bodies, which is used for measuring speed of high-speed underwater projectile bodies by the aid of electromagnetic induction coil targets and belongs to the technical fields of high-speed underwater trajectory and underwater weapons. The electromagnetic-induction speed measurement device for underwater projectile bodies comprises an electromagnetic induction device, a signal processing circuit and an oscilloscope. The electromagnetic induction device comprises a coil target and a target frame, wherein the coil target is fixed on the target frame and comprises a casing and a coil, and the casing consists of an inner ring, an outer ring, an upper connecting plate and a lower connecting plate. The electromagnetic-induction speed measurement device for underwater projectile bodies has the advantages of simple structure, less interference of water characteristics, convenience in data processing, higher precision, no influence to trajectories with cavities for high-speed underwater projectile bodies and the like, and can be used for testing speed of high-speed underwater weapons such as high-speed projectiles and the like.
Description
Technical field
The present invention relates to the electromagnetic induction speedometer of body under water, a kind of device that utilizes the electromagnetic induction coil target to realize body velocity test under the high speed water belongs to high speed water ballistics and underawater ordnance technical field.
Background technology
The density of water is about more than 800 times of atmospheric density; The coefficient of viscosity is about 100 times of air, and suffered resistance was very big when the high speed body moved under water, and the underwater speed hold facility of body is low; Show as on very short move distance, the velocity attenuation of body is serious.Simultaneously, often be accompanied by the phenomenon that low speed trajectories such as supercavity, wake flow, shock wave and noise do not have when the high speed body moves under water, these complicated trajectory characteristics are all brought certain difficulty to the velocity test of body under the high speed water.
Because the huge difference of aqueous medium characteristic and air dielectric characteristic, normalized velocity test method all is difficult to use under water in the very big aeroballistic trajectory.Aqueous medium has certain electric conductivity, is rich in conductive ion in the seawater, and electric conductivity is stronger, and this type of break-make target speed measuring device receives the influence of aqueous medium electric conductivity may improper conducting, can not be used for the test of body speed under the high speed water; Often be accompanied by supercavity when the high speed body moves under water, contact speed measuring devices such as tinfoil paper target can cause the change of supercavity form or cause cavity to come off, and change the ballistic characteristics of high speed body, thereby the speed that also can't be used to test body under the high speed water; Aqueous medium has absorption and scattering process to light; The energy of light is comparatively serious with the increase decay of propagation distance; Light curtain target, CCD for Measuring Velocity and this type of high-speed photography optically measuring speeds device are owing to receive the influence of light attenuation; Effect is not good enough during the speed that is used to test the high speed body, and the optically measuring speeds device can not be used basically in impure more, test environment that water quality is muddy.
Summary of the invention
The objective of the invention is for the speed that solves ammunition in complex water areas high speed water is difficult to test, the existing lower problem of measuring accuracy of speed measuring device under water; Having proposed the electromagnetic induction speedometer of body under water, is a kind of device that utilizes ammunition speed in the electromagnetic induction principle test high speed water.
The objective of the invention is to realize through following technical scheme.
The electromagnetic induction speedometer of body under water of the present invention, this device comprises electromagnetic induction device, signal processing circuit and oscillograph;
Electromagnetic induction device comprises coil target 8 and target holder 9, and coil target 8 is fixed on the target holder 9; Coil target 8 comprises housing and coil 2, and housing is made up of interior ring 3, outer shroud 5, upper junction plate 4 and lower connecting plate 6, and interior ring 3 is a hollow cylinder; Coiling 2 on the interior ring 3; The outside of ring 3 in outer shroud 5 places, upper junction plate 4 is on the top of housing, and lower connecting plate 6 is in the bottom of housing; In the space that ring 3, outer shroud 5, upper junction plate 4 and lower connecting plate 6 were formed in coil 2 was sealed in; 2 wire guides 1 are arranged on the outer shroud 5, be used to draw lead; Around upper junction plate 4 and the lower connecting plate 6 pilot hole 7 is arranged, be used for coil target 8 is fixed on target holder 9; The junction of coil target 8 housings utilizes fluid sealant to seal, and prevents that aqueous medium from getting into enclosure interior;
Coil 2 is the enameled wire of certain number of turn; Coil 2 coilings are even, consistance is good; The supercavity form around the satisfied not disturbed test body of its diameter and the flow at high speed of aqueous medium, the induced electromotive force signal of generation sufficient intensity when the satisfied magnetization of the number of turn of coil 2 body passes through;
The diameter of coil 2 is 15～25cm, and coil 2 numbers of turn are 100～200 circles.
Signal processing circuit comprises filtering circuit 10 and amplifying circuit 11; Filtering circuit 10 can filterings because high frequency, the noise signal in the induced electromotive force signal that the aqueous medium properties influence causes, amplifying circuit 11 can be realized the amplification to the induced electromotive force signal suitable multiple.Filtering circuit 10 comprises resistance R
1And capacitor C
1, capacitor C
2, resistance R
1Preceding termination input signal, back termination capacitor C
1, capacitor C
2An end and the inverting input of operational amplifier, capacitor C
1, capacitor C
2Other end ground connection; Amplifying circuit 11 comprises operational amplifier, resistance R
2, resistance R
3, resistance R
4And resistance R
5And capacitor C
3, capacitor C
4, the inverting input of operational amplifier connects the signal after the Filtering Processing, normal phase input end connecting resistance R
2, resistance R
2Other end ground connection, the pin 7 of operational amplifier connects capacitor C
3And resistance R
3, capacitor C
3And resistance R
3Parallel connection, capacitor C
3Other end ground connection, resistance R
3Another termination forward power supply V
Cc, the pin 4 of operational amplifier connects capacitor C
4And resistance R
4, capacitor C
4And resistance R
4Parallel connection, capacitor C
4Other end ground connection, resistance R
4Another termination negative sense power supply V
EE, resistance R
5Be variable resistor, the output terminal of one of which termination operational amplifier, the inverting input of another termination operational amplifier is realized the negative feedback of output signal, plays the effect of anti-phase amplifying signal.
Oscillographic model is TST3406, has in real time demonstration and writing function.
The course of work of the electromagnetic induction speedometer of body is under the high speed water of the present invention: when the body of magnetization processing passes coil target 8; The magnetic induction line in coil 2 cutting magnetization body magnetic fields; By electromagnetic induction principle; Produce induced electromotive force signal in the coil target 8, this signal is the target signal excessively of body.When body passes a plurality of coil target 8, will correspondingly produce a plurality of target signals of crossing.The induced electromotive force signal intensity that coil target 8 produces a little less than, and, need through filtering and processing and amplifying because the effect of impurity or other disturbing factor in the aqueous medium also possibly followed some undesired signals in the electromotive force signal.After signal processing circuit is handled, obtain the induced electromotive force signal of intensity higher and noiseless (or disturbing very little), export oscillograph to and show.Utilize oscillograph can measure the time interval of adjacent two induced electromotive force signal; And the induced electromotive force signal reaction is that body is crossed target information; The range of two coil targets 8 is fixed, and utilizes the average velocity method, can measure the average velocity of body between two coil targets 8.
Beneficial effect
That the present invention has is simple in structure, receive that the aqueous medium characteristic is disturbed little, convenient data processing, precision is higher and the band cavity trajectory of ammunition in the high speed water do not had advantage such as to influence, and can be used for the velocity test of high speed underawater ordnance such as high-velocity projectiles.
Description of drawings
Fig. 1 is the electromagnetic induction device structural representation;
Fig. 2 is the structural representation of coil target;
Fig. 3 is the plan view of coil target;
Fig. 4 is the signal processing circuit synoptic diagram;
Wherein, 1-wire guide, ring in the 2-coil, 3-, 4-upper junction plate, 5-outer shroud, 6-lower connecting plate, 7-pilot hole, 8-coil target, 9-target holder, 10-filtering circuit, 11-amplifying circuit.
Embodiment
For objects and advantages of the present invention are described better, the present invention is described further below in conjunction with accompanying drawing and embodiment.
Embodiment
The electromagnetic induction speedometer of body under water, this device comprises electromagnetic induction device, signal processing circuit and oscillograph; The effect of electromagnetic induction device is: target signal, the i.e. induced electromotive force signal excessively that produce body;
Electromagnetic induction device like Fig. 1, Fig. 2 and shown in Figure 3, comprises coil target 8 and target holder 9, and coil target 8 is fixed on the target holder 9; Coil target 8 comprises housing and coil 2, and housing is made up of interior ring 3, outer shroud 5, upper junction plate 4 and lower connecting plate 6, and interior ring 3 is a hollow cylinder; Coiling 2 on the interior ring 3; The outside of ring 3 in outer shroud 5 places, upper junction plate 4 is on the top of housing, and lower connecting plate 6 is in the bottom of housing; In the space that ring 3, outer shroud 5, upper junction plate 4 and lower connecting plate 6 were formed in coil 2 was sealed in; 2 wire guides 1 are arranged on the outer shroud 5, be used to draw lead; Around upper junction plate 4 and the lower connecting plate 6 pilot hole 7 is arranged, be used for coil target 8 is fixed on target holder 9;
Wherein, the external diameter of ring 3 is 150mm in the housing, highly is 60mm; The internal diameter of outer shroud 5 is 160mm; Highly be 50mm, the thickness of interior ring 3, outer shroud 5 is 5mm, and the thickness of upper junction plate 4, lower connecting plate 6 is 10mm; The diameter of the pilot hole 7 around upper junction plate 4, the lower connecting plate 6 is 10mm, and the material of housing is a nylon.On ring 3 housings, coil 2 diameters were 150mm in coil 2 was wound on, and the number of turn is 100, and material is an enameled wire, and the enameled wire line directly is 0.5mm, and coil 2 coilings are even, consistance is good.The junction of coil target 8 housings utilizes fluid sealant to seal, and prevents that aqueous medium from getting into enclosure interior.
The effect of signal processing circuit is: the induced electromotive force signal to electromagnetic induction device produces is carried out filtering and processing and amplifying, generates to be convenient to oscillograph demonstration and stored voltage signal; Signal processing circuit comprises filtering circuit 10 and amplifying circuit 11, and is as shown in Figure 4, high frequency, noise signal in the filtering circuit 10 ability filtering induced electromotive force signal, and amplifying circuit 11 can be realized the amplification to the induced electromotive force signal suitable multiple.Filtering circuit 10 comprises resistance R
1And capacitor C
1, capacitor C
2, resistance R
1Preceding termination input signal, back termination capacitor C
1, capacitor C
2An end and the inverting input of operational amplifier, capacitor C
1, capacitor C
2Other end ground connection; Amplifying circuit 11 comprises operational amplifier, resistance R
2, resistance R
3, resistance R
4And resistance R
5And capacitor C
3, capacitor C
4, the inverting input of operational amplifier connects the signal after the Filtering Processing, normal phase input end connecting resistance R
2, resistance R
2Other end ground connection, the pin 7 of operational amplifier connects capacitor C
3And resistance R
3, capacitor C
3And resistance R
3Parallel connection, capacitor C
3Other end ground connection, resistance R
2Another termination forward power supply V
Cc, the pin 4 of operational amplifier connects capacitor C
4And resistance R
4, capacitor C
4And resistance R
4Parallel connection, capacitor C
4Other end ground connection, resistance R
4Another termination negative sense power supply V
EE, resistance R
5Be variable resistor, the output terminal of one of which termination operational amplifier, the inverting input of another termination operational amplifier is realized the negative feedback of output signal, plays the effect of anti-phase amplifying signal.R
1=100 Ω, R
2=R
3=R
4=100 Ω, R
5=100k Ω, C
1=0.1 μ F, C
2=1 μ F, C
3=C
4=0.1 μ F, V
EE=-12V, V
Cc=12V, the operational amplifier model is LF357N.
Oscillographic model is TST3406; Its effect is: the induced electromotive force signal after handling is shown and store that it has a plurality of data acquisition channels, and has automatic triggering, demonstration and quick storage function; Can gather and write down induced electromotive force signal in real time; Have higher SF simultaneously, null position that can accurately the interpretation induction electromotive force guarantees that test data has higher precision.
Before the experiment, electromagnetic induction device is arranged according to mode shown in Figure 1, the plane of each electromagnetic induction device and surface level keeping parallelism, it is vertical with surface level that each installs the line of centres, and the distance between each device equates.Each electromagnetic induction device is connected with signal processing circuit, and the output terminal of signal processing circuit connects an oscillographic passage respectively.After connection finishes; Vertically be placed on target holder in the test pools; Signal processing circuit and oscillograph are placed on outside the pond, directly over target holder, launch body vertically downward, and emitter gun barrel center overlaps with each pinwheel line; Guarantee that the body destined trajectory overlaps with each pinwheel line, body is handled through magnetization in advance.For the ease of forming contrast; Side in test pools installs clear glass additional; And experimental water is limpid; Can use high-speed photography to take the underwater trajectories of high speed body, obtain the speed of high speed body between adjacent two coil targets, compare with the result that tests the speed of electromagnetic induction device through data processing.
Experimentation is: oscillograph is set to automatic triggering, and a less trigger voltage value is set, and like 100mV, each passage is in the triggering state of treating.Above the pond, utilize emitter Vertical Launch test body (high-velocity projectiles); Because body is handled through magnetization in advance, when its process electromagnetic induction device, by the induction electromotive force principle; The magnetic induction line in coil cutting body magnetic field; In electromagnetic induction device, produce induction electromotive force, electromotive force signal enters into oscillograph after signal processing circuit is handled.When the magnitude of voltage of the electromotive force signal that produces in first target surpasses the trigger voltage value that is provided with; The electromotive force signal that first electromagnetic induction device of oscillograph opening entry produces; And on screen, show; When body passes through each target successively, correspondingly produced the target signal in the electromagnetic induction device, and write down successively and show by oscillograph.After test finishes, utilize oscillographic data processing function to come the time interval between two adjacent induced electromotive force signal of interpretation, the distance between two targets preestablishes, and utilizes the average velocity method to calculate body through the average velocity between two targets.
Six groups of experimental datas have been tested with high-speed photography and electromagnetic induction device; Wherein to have chosen two kinds be 15cm and 20cm to range; The time and the speed data of its test are as shown in table 1, and the velocity amplitude of electromagnetic induction device test is as shown in table 1 with respect to the relative deviation of the velocity amplitude of high-speed photography test.
The velocity test result of the high speed body through analyzing present embodiment, the result's that tests the speed of the test the speed result and the high-speed photography of electromagnetic induction device relative deviation explains that electromagnetic induction speedometer has higher measuring accuracy under water in 5%.In the test environment of water quality complicacy; High-speed photography is difficult to use; But this proving installation does not receive the influence of water quality, can realize the test to complicated test environment high speed body speed, and is a kind of untouchable, proving installation of high speed body trajectory not had influence.
Table 1
Claims (5)
1. the electromagnetic induction speedometer of body under water, it is characterized in that: this device comprises electromagnetic induction device, signal processing circuit and oscillograph;
Electromagnetic induction device comprises coil target (8) and target holder (9), and coil target (8) is fixed on the target holder (9); Coil target (8) comprises housing and coil (2); Housing is made up of interior ring (3), outer shroud (5), upper junction plate (4) and lower connecting plate (6); Interior ring (3) is a hollow cylinder, and interior ring (3) is gone up coiling (2), and outer shroud (5) places the outside of interior ring (3); Upper junction plate (4) is on the top of housing, and lower connecting plate (6) is in the bottom of housing; Coil (2) is sealed in the space of interior ring (3), outer shroud (5), upper junction plate (4) and lower connecting plate (6) composition; 2 wire guides (1) are arranged on the outer shroud (5), be used to draw lead; Around upper junction plate (4) and the lower connecting plate (6) pilot hole (7) is arranged, be used for coil target (8) is fixed on target holder (9); The junction of coil target (8) housing utilizes fluid sealant to seal;
Signal processing circuit comprises filtering circuit (10) and amplifying circuit (11); Filtering circuit (10) comprises resistance R
1And capacitor C
1, capacitor C
2, resistance R
1Preceding termination input signal, back termination capacitor C
1, capacitor C
2An end and the inverting input of operational amplifier, capacitor C
1, capacitor C
2Other end ground connection; Amplifying circuit (11) comprises operational amplifier, resistance R
2, resistance R
3, resistance R
4And resistance R
5And capacitor C
3, capacitor C
4, the inverting input of operational amplifier connects the signal after the Filtering Processing, normal phase input end connecting resistance R
2, resistance R
2Other end ground connection, the pin 7 of operational amplifier connects capacitor C
3And resistance R
3, capacitor C
3And resistance R
3Parallel connection, capacitor C
3Other end ground connection, resistance R
3Another termination forward power supply V
Cc, the pin 4 of operational amplifier connects capacitor C
4And resistance R
4, capacitor C
4And resistance R
4Parallel connection, capacitor C
4Other end ground connection, resistance R
4Another termination negative sense power supply V
EE, resistance R
5Be variable resistor, the output terminal of one of which termination operational amplifier, the inverting input of another termination operational amplifier.
2. the electromagnetic induction speedometer of body under water according to claim 1 is characterized in that: coil (2) is the enameled wire of certain number of turn.
3. the electromagnetic induction speedometer of body under water according to claim 1 is characterized in that: the diameter of coil (2) is 15～25cm, and coil (2) number of turn is 100～200 circles.
4. the electromagnetic induction speedometer of body under water according to claim 1 is characterized in that: oscillographic model is TST3406.
5. the electromagnetic induction speedometer of body under water according to claim 1; It is characterized in that: when the body of magnetization processing passes coil target (8); The magnetic induction line in coil (2) cutting magnetization body magnetic field; By electromagnetic induction principle, produce induced electromotive force signal in the coil target (8), this signal is the target signal excessively of body; When body passes a plurality of coil targets (8), will correspondingly produce a plurality of target signals of crossing; The induced electromotive force signal intensity that coil target (8) produces a little less than, and, need through filtering and processing and amplifying because the effect of impurity or other disturbing factor in the aqueous medium also possibly followed some undesired signals in the electromotive force signal; After signal processing circuit is handled, obtain the induced electromotive force signal that intensity is higher and noiseless or interference is very little, export oscillograph to and show; Utilize oscillograph can measure the time interval of adjacent two induced electromotive force signal; And the induced electromotive force signal reaction is that body is crossed target information; The range of two coil targets (8) is fixed, and utilizes the average velocity method, can measure the average velocity of body between two coil targets (8).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210065175 CN102608346B (en) | 2012-01-13 | 2012-01-13 | Electromagnetic-induction speed measurement device for underwater projectile bodies |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210065175 CN102608346B (en) | 2012-01-13 | 2012-01-13 | Electromagnetic-induction speed measurement device for underwater projectile bodies |
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| CN102608346A true CN102608346A (en) | 2012-07-25 |
| CN102608346B CN102608346B (en) | 2013-07-03 |
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| CN 201210065175 Expired - Fee Related CN102608346B (en) | 2012-01-13 | 2012-01-13 | Electromagnetic-induction speed measurement device for underwater projectile bodies |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107037232A (en) * | 2016-12-16 | 2017-08-11 | 华中科技大学 | A kind of velocity measuring device and method based on electromagnetic induction |
| CN110068701A (en) * | 2019-05-05 | 2019-07-30 | 太原理工大学 | Pipeline vehicle instantaneous velocity measuring system based on electromagnetic method |
| CN113671208A (en) * | 2021-09-14 | 2021-11-19 | 西南交通大学 | Double-ring mutual inductance speed measuring device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6563302B1 (en) * | 2000-04-28 | 2003-05-13 | The United States Of America As Represented By The Secretary Of The Navy | Device for sensing projectile velocity in an underwater environment |
-
2012
- 2012-01-13 CN CN 201210065175 patent/CN102608346B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6563302B1 (en) * | 2000-04-28 | 2003-05-13 | The United States Of America As Represented By The Secretary Of The Navy | Device for sensing projectile velocity in an underwater environment |
Non-Patent Citations (2)
| Title |
|---|
| 狄长安等: "单个感应线圈在水下弹丸速度测量中的应用", 《南京理工大学学报》 * |
| 狄长安等: "线阵CCD 测量水下枪弹速度的方法", 《南京理工大学学报》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107037232A (en) * | 2016-12-16 | 2017-08-11 | 华中科技大学 | A kind of velocity measuring device and method based on electromagnetic induction |
| CN110068701A (en) * | 2019-05-05 | 2019-07-30 | 太原理工大学 | Pipeline vehicle instantaneous velocity measuring system based on electromagnetic method |
| CN113671208A (en) * | 2021-09-14 | 2021-11-19 | 西南交通大学 | Double-ring mutual inductance speed measuring device |
| CN113671208B (en) * | 2021-09-14 | 2022-05-31 | 西南交通大学 | Double-ring mutual inductance speed measuring device |
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| CN102608346B (en) | 2013-07-03 |
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Granted publication date: 20130703 Termination date: 20140113 |