Projectile parameter detection system and method of Hopkinson bar

Abstract

The invention relates to the technical field of material mechanical property testing, in particular to a bullet parameter detection system and method of a Hopkinson bar, the parameter detection system comprises at least two detection modules, a magnetic identification piece and a signal acquisition and processing unit, the at least two detection modules are arranged at an interval; the detection module comprises an induction coil annular structure and a static magnetic field annular structure, the static magnetic field annular structure is coaxially installed outside the induction coil annular structure, the induction coil annular structure comprises a plurality of quadrant partitions arranged at intervals along the circumference, and each quadrant partition is provided with a plurality of coils; the time when the projectile passes through different detection modules is collected through a signal collecting and processing unit, the flight speed of the projectile is obtained by combining the distance of the detection modules, and the rotating state and the coaxial posture of the projectile are obtained by collecting signals generated by each quadrant partition when the projectile passes through the detection modules; according to the parameter detection method, multi-parameter synchronous detection can be completed in a non-contact mode, limitation of the projectile structure is avoided, universality is higher, and reliability is better.

Description

Technical Field

[0001] This invention relates to the field of material mechanical property testing technology, specifically to a projectile parameter detection system and method for a Hopkinson bar. Background Technology

[0002] The Hopkinson bar (SHPB) is a core piece of equipment for studying the dynamic mechanical properties of materials at high strain rates. Precise control of its projectile launch parameters is crucial to ensuring the reliability of experiments.

[0003] Existing methods for detecting the projectile launch parameters of the Hopkinson rod mainly include the laser interruption method, the contact wire method, and the single-coil electromagnetic induction method. The laser interruption method calculates the projectile velocity by the time difference between the projectile's passage through two laser beams; the contact wire method triggers a passing signal by causing a short circuit when the projectile contacts the wire; and the single-coil electromagnetic induction method determines the projectile's transit time through electromagnetic induction. In the Hopkinson rod experiment, the projectile is required to impact the incident rod at a velocity of 5–40 m / s, and stress wave eccentricity must be avoided to prevent centrifugal force from causing projectile attitude deviation. Direct contact with the projectile must also be avoided to prevent interference with the experimental process. Therefore, it is necessary to detect the projectile's velocity, rotational state, and coaxial attitude. However, existing methods for detecting the projectile launch parameters of the Hopkinson rod are difficult to simultaneously achieve high-precision detection of these multiple parameters. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing Hopkinson rod projectile launch parameter detection methods, which are difficult to achieve multi-parameter synchronous high-precision detection, and to provide a Hopkinson rod projectile parameter detection system and method.

[0005] In a first aspect, the present invention provides a projectile parameter detection system for a Hopkinson bar, comprising: The detection module, at least two of which are spaced apart along the projectile launch direction, has a through detection channel. The detection module includes an induction coil ring structure and a static magnetic field ring structure. The static magnetic field ring structure is coaxially mounted outside the induction coil ring structure. The induction coil ring structure includes several quadrant partitions spaced apart along the circumference. Each quadrant partition is provided with several coils. A magnetic marker is disposed on a projectile, which is driven through the detection channel by a Hopkinson rod; A signal acquisition and processing unit is used to receive and process the signal generated when the projectile passes through the detection module.

[0006] Preferably, the induction coil ring structure includes a full-ring coil assembly and a partitioned coil assembly. The full-ring coil assembly is located between the Hopkinson rod and the partitioned coil assembly. The full-ring coil assembly is uniformly wound around the coil, and the partitioned coil assembly is wound around the coil according to the quadrants.

[0007] Preferably, the static magnetic field ring structure includes a ring-shaped permanent magnet.

[0008] Preferably, the projectile comprises an aluminum rod component or an iron rod component.

[0009] Preferably, the diameter of the projectile is 6-50 mm, and the velocity of the projectile is 5-40 m / s.

[0010] Preferably, the signal acquisition and processing unit includes a controller and a hardware reconfigurable computing module. The signal acquisition and processing unit is configured to acquire the time signal of the projectile passing through the detection module, the trigger pulse signal of the projectile passing through the full-loop coil assembly, and a plurality of output voltage signals and spike pulse signals generated by the projectile passing through the partitioned coil assembly.

[0011] In a second aspect, the present invention provides a method for detecting the projectile parameters of a Hopkinson bar, employing a projectile parameter detection system for a Hopkinson bar as described above, and comprising the following steps: S1. Determine the spacing L of the detection modules and obtain the time it takes for the projectile to pass through the first detection module. The time after the projectile passes through any of the detection modules The flight speed of the projectile is calculated and determined. S2. Obtain the output voltage signal of the induction coil ring structure when the projectile passes by. - , for The offset coordinates, eccentricity distance, and offset direction of the projectile are calculated and determined by sequentially numbering the quadrant partitions clockwise. S3. Obtain the time difference between the spike pulse signal generated when the projectile passes through the first induction coil ring structure and any subsequent induction coil ring structure. The rotational speed and direction of rotation of the projectile are determined.

[0012] Preferably, the system further includes: mechanically adjusting the position of the projectile to establish a linear relationship between the projectile's offset ratio in the X or Y direction and the actual offset, and performing system calibration.

[0013] Preferably, the flight speed of the projectile satisfies: ; In the formula, The projectile's flight speed; The spacing between the two full-loop coil assemblies; The flight time of the projectile between the two detection modules. .

[0014] Preferably, the offset coordinates of the projectile ( , )satisfy: ; ; In the formula, The offset ratio of the magnetic marker on the projectile in the X direction; The offset ratio of the magnetic marker on the projectile in the Y direction; It is the angle between two adjacent quadrants; The number of quadrant partitions; for The sequence number of each quadrant partition in clockwise order; For the first The output voltage signal of the induction coil ring structure collected in each quadrant partition; The eccentricity distance satisfy: ; In the formula, The inner radius of the annular structure of the induction coil; The offset direction satisfy: .

[0015] Preferably, the rotation speed satisfy: , In the formula, The angle of rotation of the projectile as it passes between the two detection modules. ; This represents the time difference of the spike pulse signal.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a projectile parameter detection system for a Hopkinson bar. A signal acquisition and processing unit collects the time it takes for a magnetic marker on the projectile to pass through different detection modules. Combined with the distance between the detection modules, the projectile's flight velocity can be obtained. By setting up an induction coil ring structure with multiple quadrant zone coils, the system collects the corresponding signals generated by each quadrant zone when the magnetic marker on the projectile passes through the detection modules, thus obtaining the projectile's rotational state and coaxial attitude with the detection modules. This system enables non-contact, multi-parameter synchronous detection of Hopkinson bar projectile launch, is not limited by the projectile structure, has higher versatility and better reliability, avoids invalid material property data caused by stress wave eccentricity, and improves detection accuracy. 2. This invention provides a method for detecting projectile parameters of a Hopkinson rod. By employing the projectile parameter detection system of the Hopkinson rod described above, it is possible to simultaneously detect and output multiple parameters such as projectile flight speed, concentricity, rotational speed, and direction in a non-contact state. The detection accuracy is high, the versatility is high, and the reliability is good. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a projectile parameter detection system for a Hopkinson bar, as shown in Example 1.

[0018] Figure 2 This is a schematic diagram of the structure of the full-ring coil assembly described in Example 1.

[0019] Figure 3 This is a schematic diagram of the partitioned coil assembly described in Example 1.

[0020] Figure 4 This is a schematic diagram of the structure of the projectile described in Example 1.

[0021] Figure 5 This is a signal processing flowchart of a projectile parameter detection method for a Hopkinson bar, as shown in Example 2.

[0022] Marked in the image: 1-Detection module, 2-Detection channel, 3-Induction coil ring structure, 31-Full ring coil assembly, 32-Partitioned coil assembly, 33-Quadrant partition, 4-Static magnetic field ring structure, 5-Projectile, 51-Magnetic marker, 6-Hopkinson rod, 7-Signal acquisition and processing unit. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0024] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0025] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0026] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0027] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0028] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0029] Example 1 like Figures 1-4 As shown, this embodiment of a projectile parameter detection system for a Hopkinson rod is illustrated using two detection modules 1 as an example. The system includes a detection module 1, a magnetic marker 51, and a signal acquisition and processing unit 7. The two detection modules 1 are spaced apart in front of the Hopkinson rod 6 along the projectile 5's firing direction. Each detection module 1 has a detection channel 2 that axially connects to the Hopkinson rod 6. Each detection module 1 includes an induction coil ring structure 3 and a static magnetic field ring structure 4. The static magnetic field ring structure 4 is coaxially mounted outside the induction coil ring structure 3. The induction coil ring structure 3 includes several quadrant partitions 33 spaced apart along its circumference. Each quadrant partition 33 has several coils. The magnetic marker 51 is mounted on the projectile 5. The projectile 5 is driven through the detection channel 2 by the Hopkinson rod 6. The signal acquisition and processing unit 7 receives and processes the signal generated when the projectile 5 passes through the detection module 1.

[0030] The detection module 1 consists of an induction coil ring structure 3 and a static magnetic field ring structure 4. The induction coil ring structure 3 can provide a controllable electromagnetic field, and the static magnetic field ring structure 4 can provide a static magnetic field. The detection channel 2 passes through the induction coil ring structure 3 and the static magnetic field ring structure 4 along their axial directions.

[0031] The magnetic marker 51 can be a magnetic structure set on the projectile 5. It is used to cut the magnetic field of the induction coil ring structure 3 and the static magnetic field ring structure 4 by the relative movement between the magnetic marker 51 and the detection module 1, thereby generating a corresponding trigger signal for the detection and calculation of relevant parameters of the projectile 5.

[0032] In an optional implementation, the static magnetic field ring structure 4 can be a ring-shaped permanent magnet.

[0033] In an optional embodiment, the static magnetic field ring structure 4 may be formed by winding an induction coil on a magnetic conductor and providing a constant DC current to the induction coil.

[0034] In an optional implementation, the relative positions of the induction coil ring structure 3 and the static magnetic field ring structure 4 can be stabilized by an external support structure.

[0035] In an optional embodiment, the magnetic marker 51 can be a flexible magnetic patch, a plurality of magnetic patches arranged in a ring, or a single magnetic patch. It can be embedded in the surface of the projectile 5 or pasted on the surface of the projectile 5. The magnetic marker 51 is preferably square in shape and is pasted with a flexible material to prevent weight bias from affecting the flight parameters of the projectile 5.

[0036] In an optional embodiment, the projectile 5 may be an aluminum rod component or an iron rod component.

[0037] In an optional implementation, the diameter of the projectile 5 can be 6-50mm, and the velocity of the projectile 5 can be 5-40m / s.

[0038] In one or more embodiments, the induction coil ring structure 3 includes a full-ring coil assembly 31 and a partitioned coil assembly 32. The full-ring coil assembly 31 is located between the Hopkinson rod 6 and the partitioned coil assembly 32. The full-ring coil assembly 31 is uniformly wound with coils, and the partitioned coil assembly 32 is wound with coils according to quadrant partitions 33.

[0039] In an optional embodiment, the full-ring coil assembly 31 can be formed by a coil of several turns evenly distributed radially on a circular magnetic conductor. The voltage transition of the full-ring coil assembly 31 can be shaped by a comparator when the projectile 5 passes by, generating a trigger pulse signal, which can be used to indicate the time when the projectile 5 passes by, and can be used to measure the speed of the projectile 5.

[0040] In an alternative implementation, the full-to-loop coil assembly 31 may be a 256-quadrant toroidal coil.

[0041] In an optional embodiment, the partitioned coil assembly 32 can be formed by partially winding a coil of several turns on a circular magnetic conductor. The partitioned coil assembly 32 can sense changes in the magnetic field through the coils of the multi-quadrant partitions 33 to measure the eccentricity and rotation state of the projectile 5. The more quadrant partitions 33 there are, the higher the corresponding measurement accuracy. Taking the partitioned coil assembly 32 of four quadrant partitions 33 as an example, the partitioned coil assembly 32 of four quadrant partitions 33 can be formed by winding a coil of several turns in the 0°, 90°, 180°, and 270° directions of the circular magnetic conductor, which can respectively mark the upper, right, lower, and left directions of the circular magnetic conductor.

[0042] In an optional implementation, the wire diameter of each coil turn can be 0.15 mm, and the number of coil turns in each quadrant partition 33 can be set to 150-200 turns.

[0043] The signal acquisition and processing unit 7 includes a controller and a hardware reconfigurable computing module. The signal acquisition and processing unit 7 is configured to acquire the time signal of the projectile 5 passing through the detection module 1, the trigger pulse signal of the projectile 5 passing through the full-loop coil assembly 31, and several output voltage signals and spike pulse signals generated by the projectile 5 passing through the partitioned coil assembly 32. The coil output signal can be sent to the high-speed data acquisition card after low-noise amplification and bandpass filtering.

[0044] In optional implementations, the low-noise amplification can be 10-20 times, the bandpass filtering can be 5-50 kHz, and the high-speed data acquisition card parameters can be 200 kS / s and 14 bits.

[0045] In an optional implementation, the controller can be an STM32H7, and the hardware reconfigurable computing module can be an Artix-7. Through the hardware structure of the combination of MCU and FPGA, and with the embedded ST language program, high-speed signal acquisition and real-time processing can be realized.

[0046] In an optional implementation, the ST language program may include a TOF timing module, a coaxial attitude analysis module, and a rotation detection module 1.

[0047] This embodiment of a Hopkinson rod projectile parameter detection system uses a signal acquisition and processing unit 7 to collect the time it takes for the magnetic marker 51 on the projectile 5 to pass through different detection modules 1. Combined with the distance of the detection modules 1, the flight speed of the projectile 5 can be obtained. By setting an induction coil ring structure 3 with multiple quadrant partitions 33 coils, the corresponding signals generated by each quadrant partition 33 when the magnetic marker 51 on the projectile 5 passes through the detection module 1 can be collected. The rotation state of the projectile 5 and its coaxial attitude with the detection module 1 can be calculated and obtained. This system can achieve non-contact multi-parameter synchronous detection of the Hopkinson rod 6 projectile 5 launch, and is not limited by the structure of the projectile 5. It has higher versatility and better reliability, and can avoid invalid material property data caused by stress wave eccentricity, thus improving detection accuracy.

[0048] Example 2 like Figure 5 As shown, a method for detecting the projectile parameters of a Hopkinson bar uses a projectile parameter detection system for a Hopkinson bar as described in Example 1, and includes the following steps: S1. Determine the spacing L of the detection modules 1, and obtain the time it takes for the projectile 5 to pass through the first detection module 1. The time after projectile 5 passes through any detection module 1 The flight speed of projectile 5 was calculated and determined.

[0049] S1 is used to obtain the flight speed of projectile 5 based on the bistatic TOF method.

[0050] In an optional implementation, the time it takes for the projectile 5 to pass through the detection module 1 can be determined by the voltage transition of the full-loop coil assembly 31 when the projectile 5 passes through it. This voltage transition is shaped by a comparator to generate a trigger pulse, and the trigger time when the projectile 5 passes through the two detection modules 1 is recorded by the FPGA. and This allows for a projectile speed of 5.

[0051] In an optional implementation, the flight speed of projectile 5 satisfies: ; In the formula, The projectile's flight speed is 5. The spacing between the two full-ring coil assemblies 31; For the flight time of projectile 5 between the two detection modules 1, .

[0052] Furthermore, the system accuracy was verified by using a 10MHz timer clock with a resolution of 0.1μs and a velocity error of ≤1%. When the projectile 5 was launched at v=25m / s and Δt=1.2ms, the velocity error was ≤0.008%.

[0053] S2. Obtain the output voltage signal of the induction coil ring structure 3 when the projectile 5 passes by. - , for The quadrant partitions 33 are numbered clockwise, and each quadrant partition 33 corresponds to a measuring point. The offset coordinates, eccentricity distance and offset direction of the projectile 5 are calculated and determined.

[0054] S2 is used to perform attitude detection of projectile 5 based on the amplitude analysis of the multi-zone signal generated by the coil assembly 32 of each zone after the projectile 5 passes through each zone.

[0055] In an optional implementation, the offset coordinates of the projectile 5 ( , )satisfy: ; ; In the formula, The offset ratio of the magnetic marker 51 on the projectile 5 in the X direction is dimensionless. The offset ratio of the magnetic marker 51 on the projectile 5 in the Y direction is dimensionless. It is the angle between two adjacent quadrant partitions 33; The number of quadrant partitions is 33; for The sequence numbers of the 33 quadrant partitions in clockwise order; For the first The azimuth angle corresponding to quadrant partition 33 is the first quadrant partition. The angle of each quadrant partition 33 relative to the positive X-axis direction; For the first The output voltage signal of the induction coil ring structure 3 collected in quadrant partition 33, in volts.

[0056] In an optional implementation, taking the four quadrant partitions 33 of Coil1 to Coil4 as an example, when the projectile 5 passes through the detection module 1, the coils of the four quadrant partitions 33 induce changes in magnetic fields, and the output voltage changes accordingly. ~ , ~ These represent the voltage outputs of coils 1 through 4 (in the order of top, right, bottom, left), and the X-direction offset ratio of projectile 5. Y-direction offset ratio .

[0057] In an optional implementation, the eccentricity of the projectile 5 can be controlled by the eccentricity distance. It means that the conditions are met. ; In the formula, r is the actual eccentricity distance, in mm; The inner radius of the induction coil ring structure 3 is in mm.

[0058] In an optional implementation, the eccentric direction of the projectile 5 can be represented by the deflection angle between the axis and the horizontal line when the magnetic marker 51 passes through the detection module 1, satisfying the following requirements: ,in The absolute angle of the magnetic marker 51 at the two detection modules 1 can be calculated from the signals of the four quadrant partitions 33.

[0059] Furthermore, by mechanically adjusting the position of projectile 5, a system is established. / The linear relationship with the actual offset allows for system calibration with an accuracy of ≤0.02mm.

[0060] S3. Obtain the time difference between the spike pulse signal generated when the projectile 5 passes through the first induction coil ring structure 3 and any subsequent induction coil ring structure 3. The rotational speed and direction of rotation of projectile 5 are determined.

[0061] S3 is used to detect the rotation state of the projectile 5 based on the pulse analysis of the magnetic marker 51 generated by the projectile 5 passing through each partition coil assembly 32. According to the spike pulse signal output by the coils of the four quadrant partitions 33 when the magnetic marker 51 passes through the two partition coil assemblies 32, the rotation direction of the projectile 5 after passing through the two detection modules 1 can be determined. For example, when the first partition coil assembly 32 outputs a spike pulse corresponding to the right quadrant, the next partition coil assembly 32 outputs a spike pulse corresponding to the upper quadrant, and thus the rotation direction can be determined to be counterclockwise.

[0062] In an optional implementation, the rotational speed of the projectile 5 satisfy: , In the formula, The angle of rotation of projectile 5 as it passes between the two detection modules 1. ; This represents the time difference of the spike pulse signal.

[0063] To further verify the experimental accuracy of the projectile parameter detection method for a Hopkinson rod in this embodiment, a steel rod with a diameter of 16 mm and a length of 50 mm was used as the projectile 5. A 3×3×2 mm radial magnet was embedded in the surface of the projectile 5 as a magnetic marker 51. The experimental conditions were set as follows: speed 20 m / s, coaxial attitude intentionally offset by 0.01 mm in the X direction and 0.005 mm in the Y direction, rotation speed 1000 rpm, clockwise direction. The projectile parameter detection method of this embodiment and the projectile parameter detection system of embodiment 1 were used for detection. The detection results were as follows: projectile 5 flight speed v = 20.05 m / s (error 0.25%), concentricity r = 0.012 mm (error 20%), rotation speed 998 rpm, and direction clockwise (accuracy 100%).

[0064] Upon testing, the projectile parameter detection method of the Hopkinson rod in this embodiment has an output speed error of ≤1% and a concentricity error of ≤0.02mm corresponding to a projectile flight speed of 2-25m / s, and an error of ≤2% corresponding to a rotation speed of 0-5000rpm, with a direction judgment accuracy of 100%.

[0065] This embodiment of a Hopkinson bar projectile parameter detection method employs a Hopkinson bar projectile parameter detection system from Embodiment 1. It achieves precise sensing of magnetic field distribution through multi-quadrant coils, solving the coaxial attitude detection problem. A rotational characteristic signal is provided by a magnetic marker 51, making it adaptable to projectile structures such as iron or aluminum rods, exhibiting high versatility. The rotation direction judgment accuracy is 100%, and high-precision time interval measurement ensures speed accuracy ≤1%, resulting in good reliability. Simultaneously, speed, coaxial attitude, and rotation information are extracted non-contactly from the coil signals of the same detection module 1, enabling simultaneous detection and output of multiple parameters. This avoids the influence of contact methods on the projectile's trajectory errors. The signal processing delay is ≤10μs, meeting the high-speed experimental requirements of the Hopkinson bar, and providing high detection accuracy. Coaxial attitude monitoring avoids invalid material property data caused by stress wave eccentricity.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A projectile parameter detection system for a Hopkinson bar, characterized in that, include: The detection module (1) is provided with at least two detection modules (1) arranged at intervals along the launching direction of the projectile (5). The detection module (1) is provided with a through detection channel (2). The detection module (1) includes an induction coil ring structure (3) and a static magnetic field ring structure (4). The static magnetic field ring structure (4) is coaxially installed outside the induction coil ring structure (3). The induction coil ring structure (3) includes a number of quadrant partitions (33) arranged at intervals along the circumference. Each quadrant partition (33) is provided with a number of coils. A magnetic marker (51) is disposed on a projectile (5), which is driven through the detection channel (2) by a Hopkinson rod (6); The signal acquisition and processing unit (7) is used to receive and process the signal generated when the projectile (5) passes through the detection module (1).

2. The projectile parameter detection system for a Hopkinson bar according to claim 1, characterized in that, The induction coil ring structure (3) includes a full-ring coil assembly (31) and a partitioned coil assembly (32). The full-ring coil assembly (31) is located between the Hopkinson rod (6) and the partitioned coil assembly (32). The full-ring coil assembly (31) is uniformly wound with a coil, and the partitioned coil assembly (32) is wound with a coil according to the quadrant partitions (33).

3. The projectile parameter detection system for a Hopkinson bar according to claim 1, characterized in that, The static magnetic field ring structure (4) includes a ring permanent magnet.

4. The projectile parameter detection system for a Hopkinson bar according to claim 1, characterized in that, The projectile (5) includes an aluminum rod component or an iron rod component.

5. The projectile parameter detection system for a Hopkinson bar according to claim 1, characterized in that, The diameter of the projectile (5) is 6-50mm, and the velocity of the projectile (5) is 5-40m / s.

6. The projectile parameter detection system for a Hopkinson bar according to claim 2, characterized in that, The signal acquisition and processing unit (7) includes a controller and a hardware reconfigurable computing module. The signal acquisition and processing unit (7) is configured to acquire the time signal of the projectile (5) passing through the detection module (1), the trigger pulse signal of the projectile (5) passing through the full-ring coil assembly (31), and a number of output voltage signals and spike pulse signals generated by the projectile (5) passing through the partitioned coil assembly (32).

7. A method for detecting projectile parameters using a Hopkinson bar, characterized in that, A projectile (5) parameter detection system using a Hopkinson bar (6) as described in any one of claims 1-6, comprising the following steps: S1. Determine the spacing L of the detection modules (1) and obtain the time it takes for the projectile (5) to pass through the first detection module (1). The time it takes for the projectile (5) to pass through any of the detection modules (1) The flight speed of the projectile (5) is calculated and determined. S2. Obtain the output voltage signal of the induction coil ring structure (3) when the projectile (5) passes by. - , for The offset coordinates, eccentricity distance and offset direction of the projectile (5) are calculated and determined by the clockwise sequential numbering of the quadrant partitions (33); S3. Obtain the time difference between the spike pulse signal generated when the projectile (5) passes through the first induction coil ring structure (3) and any subsequent induction coil ring structure (3). The rotational speed and direction of rotation of the projectile (5) are determined.

8. The method for detecting projectile parameters of a Hopkinson bar according to claim 7, characterized in that, The flight speed of the projectile (5) satisfies: ; In the formula, The flight speed of the projectile (5); The spacing between the two full-ring coil assemblies (31); For the flight time of the projectile (5) between the two detection modules (1), .

9. The method for detecting projectile parameters of a Hopkinson bar according to claim 7, characterized in that, The offset coordinates of the projectile (5) , )satisfy: ； ； In the formula, The offset ratio of the magnetic marker (51) on the projectile (5) in the X direction; The offset ratio of the magnetic marker (51) on the projectile (5) in the Y direction; The angle between two adjacent quadrant partitions (33); The number of quadrant partitions (33); for The quadrant partitions (33) are numbered in a clockwise order; For the first The output voltage signal of the induction coil ring structure (3) collected by each quadrant partition (33); The eccentricity distance satisfy: ; In the formula, The inner ring radius of the induction coil ring structure (3) is given by the inner ring radius. The offset direction satisfy: .

10. The method for detecting projectile parameters of a Hopkinson bar according to claim 9, characterized in that, The rotation speed satisfy: , In the formula, The angle through which the projectile (5) turns between the two detection modules (1), ; This represents the time difference of the spike pulse signal.

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