Explosive material identification and imaging method and system based on x-ray backscattering

Abstract

The application provides an explosive substance identification and imaging method and system based on X-ray backscattering, theoretical curves are drawn according to the high-energy and low-energy backscattering ray intensity theoretical values of different categories of substances in the explosive, the regions corresponding to each substance are divided based on the distribution of the actual high-energy and low-energy backscattering ray intensity data of different categories of substances around the respective theoretical curves, and the corresponding substance category is determined through the region where the actual high-energy and low-energy backscattering ray intensity data of the substance to be measured in the explosive is located. The method is more accurate than the existing method of directly using a straight line to divide the region to determine the substance category, has smaller algorithm operation amount, and is faster in operation, assists explosive disposal personnel in formulating an explosive disposal scheme, and improves the accuracy and success rate of explosive disposal.

Description

Technical Field

[0001] This invention belongs to the field of material detection and identification technology, and particularly relates to a method and system for identifying and imaging explosive materials based on X-ray backscattering. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] X-ray backscattering imaging (RSI) is considered an effective method for detecting explosives. This method is based on the Compton effect: when X-rays strike an object, most pass through, some are absorbed, and a small portion is reflected. X-rays scatter differently depending on the object they encounter: materials with low atomic numbers scatter more strongly, while materials with high atomic numbers scatter less. Therefore, RSI is more sensitive than transmission imaging for detecting low-density materials, making it more suitable for detecting lightweight materials like explosives. Furthermore, the shape and defect indications do not overlap, allowing for the detection of geometrically complex and multi-layered objects.

[0004] However, due to inherent technical limitations such as low imaging efficiency and image resolution, low receiving sensitivity, and high image noise, X-ray backscatter imaging technology restricts its practical application in rapid operations such as urban counter-terrorism and road mobile operations. Furthermore, during actual detection, inorganic components such as wires and circuits in explosives are easily lost, making it impossible for bomb disposal personnel to accurately assess the internal structure of the explosives. This poses a significant challenge to developing effective dismantling plans. Therefore, accurately identifying the internal components of explosives to facilitate the development of effective dismantling strategies is a problem that needs to be solved. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention provides a method and system for identifying and imaging explosive materials based on X-ray backscattering. By analyzing and calculating the backscattered ray intensity of the main components in the explosive, the backscattered intensity data of each component are separated using boundary curves. This allows for the rapid differentiation of different material categories in the explosive, assisting bomb disposal personnel in formulating bomb disposal plans and improving the accuracy and success rate of bomb disposal.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for identifying and imaging explosive materials based on X-ray backscattering, comprising: Based on the variation of theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive with different material thicknesses, theoretical curves corresponding to different types of substances are obtained. Based on the distribution of high and low energy backscattering intensity data actually produced by different types of materials around the corresponding theoretical curves, the theoretical curve is divided into multiple regions, each region corresponding to a type of material. The intensity data of high and low energy backscattered rays of the substance to be tested inside the explosive are obtained. Based on the division of the region where the obtained high and low energy backscattered ray intensity data is located, the category of the substance to be tested inside the explosive is obtained.

[0007] A second aspect of the present invention provides an explosive material identification and imaging system based on X-ray backscattering, comprising: Analysis module: Based on the changes in the theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive and their thickness, theoretical curves corresponding to different types of substances are obtained. Division module: Based on the distribution of high and low energy backscattering intensity data actually produced by different types of materials around the corresponding theoretical curve, the theoretical curve is divided into multiple division regions, each of which corresponds to a type of material; Category Detection Module: Acquires high and low energy backscattered ray intensity data of the substance to be tested inside the explosive, and determines the category of the substance to be tested inside the explosive based on the division region where the acquired high and low energy backscattered ray intensity data is located.

[0008] A third aspect of the present invention provides a computer device comprising: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the computer device is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, an explosive material identification and imaging method based on X-ray backscattering is performed.

[0009] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs a method for identifying and imaging explosive materials based on X-ray backscattering.

[0010] The above one or more technical solutions have the following beneficial effects: In this invention, theoretical curves are plotted based on the theoretical values ​​of high and low energy backscattered ray intensities of different types of substances in an explosive. Based on the distribution of actual high and low energy backscattered ray intensities of different types of substances around their respective theoretical curves, the regions corresponding to each substance are divided. The corresponding substance category is determined by the region where the actual high and low energy backscattered ray intensities of the substance to be tested within the explosive are located. Compared with the existing method of directly dividing regions using straight lines to determine the substance category, this method is more accurate, has less computational load, and is faster, assisting bomb disposal personnel in formulating bomb disposal plans and improving the accuracy and success rate of bomb disposal.

[0011] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0012] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0013] Figure 1 This is a schematic diagram of a dual-energy backscattering structure. Figure 2 This is a schematic diagram showing the high and low energy backscattering intensities of the three materials as the thickness increases in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram showing the distribution of experimental results for the three substances in Example 1 of the present invention; Figure 4 This is a schematic diagram showing the boundary division of the experimental results of the three substances in Embodiment 1 of the present invention. Detailed Implementation

[0014] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0015] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0016] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0017] Example 1 This embodiment discloses a method for identifying and imaging explosive materials based on X-ray backscattering, including: Based on the variation of theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive with different material thicknesses, theoretical curves corresponding to different types of substances are obtained. Based on the distribution of high and low energy backscattering intensity data actually produced by different types of materials around the corresponding theoretical curves, the theoretical curve is divided into multiple regions, each region corresponding to a type of material. The intensity data of high and low energy backscattered rays of the substance to be tested inside the explosive are obtained. Based on the division of the region where the obtained high and low energy backscattered ray intensity data is located, the category of the substance to be tested inside the explosive is obtained.

[0018] This embodiment analyzes and calculates the backscattered radiation intensity of the main components in the explosive, and uses boundary curves to separate the backscattered radiation intensity data of each component, so as to quickly distinguish organic, inorganic and mixed substances in the explosive, and mark them with orange, blue and green of different saturations. Then, the distribution of wire explosives inside the explosive can be obtained from the pseudo-color image, which helps bomb disposal personnel to formulate bomb disposal plans and improves the accuracy and success rate of bomb disposal.

[0019] In this embodiment, firstly, based on X-ray dual-domain backscattering imaging, a scanning image is generated by receiving Compton backscattered light from different energy domains generated by the explosive through a high-energy detector and a low-energy detector, respectively. At the same time, the received X-ray intensity signal is processed to identify the type of substance.

[0020] The theoretical value of the X-ray intensity received by the detector can be calculated using the following formula: (1) in, For the detector received X X-ray intensity, and These are the incident energy and the scattered energy, respectively; μ is the mass decay coefficient of the matter. It is the differential scattering cross section; Density of the substance; The scattering angle The maximum scattering angle that the detector can receive varies with scattering depth. The change is where d is the maximum scattering depth of the substance.

[0021] The common components in explosives fall into three main categories: first, the explosives and fuels in explosives are organic; second, the wires, circuits and other inorganic components in explosives; and third, the explosive casing and other mixtures. According to formula (1), the physical quantities of representative substances in the three categories are substituted. In this embodiment, organic TNT, inorganic metal wires and mixtures explosive casing are used as examples. A, B and C represent the three types of substances without making specific correspondences. The relationship between the high and low energy backscattering intensity of each substance with different thicknesses is plotted to obtain a theoretical curve similar to that shown in Figure 2.

[0022] like Figure 3 As shown, however, in actual detection, due to the resolution of the detector and various environmental factors, the data detected by the high and low energy detectors are discrete points close to the theoretical curve. This makes the backscatter intensity data of a certain substance distributed in the area near the theoretical curve when identifying the substance. In order to make the substance identification in actual use faster and ensure accuracy, by observing the distribution range of the discrete points of the three types of substances, two function curves are found to roughly mark the boundaries of the data points of the three types of substances. As can be seen from formula (1), the theoretical value of the data is obtained by exponential function calculation. Based on the boundary curve of the data cluster in actual detection and considering the reduction of data processing computation to improve detection speed, a quadratic function curve fitting is selected to realize the division of the material region boundary.

[0023] Taking the boundary curve of substances A and B as an example, a method for determining the boundary curve is given: 1) The theoretical distribution curves of high and low energy backscattering intensities for substance B are determined using a polynomial fitting method based on theoretical data points. Since the theoretical data distribution curves exhibit a single and clear trend, a quadratic polynomial is sufficient to fit the theoretical curves. A parameter with a coefficient of determination closer to 1 is selected to characterize the theoretical curves of substance B, denoted as [parameter name missing]. .

[0024] 2) After determining the fitted curve of substance B, use it as a reference value and decrease... The fitted curve is adjusted to change towards the boundaries of A and B. The boundary curve function during the adjustment process is initially denoted as... .

[0025] 3) Substitute the experimentally measured data points for substances A and B into the boundary curve: like or If the boundary curve is valid for dividing the data point, then the boundary curve is valid; otherwise... or If so, it means that the boundary curve has incorrectly divided the data point.

[0026] By adjusting To reduce the error rate in dividing data points by the boundary curve, a predetermined error limit is determined. When the error rate of data point partitioning is lower than Take the corresponding time As coefficients of the boundary curve function. Finally, boundary curve 1 for A and B is determined: .

[0027] Similarly, boundary curves 2 for B and C are determined: .

[0028] Furthermore, by using two boundary curves, the data points near the three theoretical curves are characterized as three material regions, such as... Figure 4 As shown.

[0029] Therefore, the method to identify which material region the measured backscattered ray intensity data falls into is as follows: (1) After the explosive undergoes Compton backscattering, the high-energy and low-energy detectors acquire backscattered ray intensity data in the high-energy and low-energy ranges, respectively.

[0030] (2) The values ​​obtained by the low-energy detector Substituting the boundary curve 1 function, if If the data point is located within the region of substance A, then the substance is substance A. If the data point is located below region A, it is either substance B or substance C.

[0031] (3) If The value obtained by the low-energy detector Substituting the boundary curve 2 function, if If the data point is located within the region of substance B, then the substance is substance B. If... If the data point is located within the region of substance C, then the substance is substance C.

[0032] By performing up to two multiplication operations on the data received by the detector, the type of substance can be identified relatively accurately and quickly. A single complete scan can distinguish the explosive components, wiring circuitry, and the explosive casing within the explosive device. Finally, based on the substance identification results, the explosive components, wiring circuitry, and explosive casing are marked with orange, blue, and green respectively, making the internal structure of the explosive device clearer and assisting bomb disposal personnel in their work.

[0033] Example 2 The purpose of this embodiment is to provide an explosive material identification and imaging system based on X-ray backscattering, including: Analysis module: Based on the changes in the theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive and their thickness, theoretical curves corresponding to different types of substances are obtained. Division module: Based on the distribution of high and low energy backscattering intensity data actually produced by different types of materials around the corresponding theoretical curve, the theoretical curve is divided into multiple division regions, each of which corresponds to a type of material; Category Detection Module: Acquires high and low energy backscattered ray intensity data of the substance to be tested inside the explosive, and determines the category of the substance to be tested inside the explosive based on the division region where the acquired high and low energy backscattered ray intensity data is located.

[0034] Example 3 The purpose of this embodiment is to provide a computing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described method.

[0035] Example 4 The purpose of this embodiment is to provide a computer-readable storage medium.

[0036] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the above method.

[0037] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0038] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0039] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for identifying and imaging explosive materials based on X-ray backscattering, characterized in that, include: Based on the variation of theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive with different material thicknesses, theoretical curves corresponding to different types of substances are obtained. Based on the distribution of high and low energy backscattering intensity data actually generated by different types of materials around the corresponding theoretical curves, the theoretical curve is divided into multiple regions, with each region corresponding to a type of material. Acquire high and low energy backscattered ray intensity data of the substance to be tested inside the explosive, and determine the category of the substance to be tested inside the explosive based on the division region where the acquired high and low energy backscattered ray intensity data is located. Different regions are divided using curves corresponding to different quadratic functions. The high and low energy backscattered ray intensity data of the substance to be tested are substituted into different quadratic functions for calculation. The category of the substance to be tested is determined based on the relationship between the calculation result and zero. The high- and low-energy backscattered ray intensity data of the analyte are substituted into different quadratic functions for calculation. Based on the relationship between the calculation results and zero, the category of the analyte is determined. Specifically: The first category of substances and the second category of substances are divided into regions using the curve corresponding to the first quadratic function, and the second category of substances and the third category of substances are divided using the curve corresponding to the second quadratic function. If the value of the high-energy backscattered ray intensity data of the substance to be tested inside the explosive is greater than the value obtained by substituting the low-energy backscattered ray intensity data of the substance to be tested inside the explosive into the first quadratic function, then the substance to be tested is a first-class substance. If the value of the high-energy backscattered ray intensity data of the substance to be tested inside the explosive is less than the value obtained by substituting the low-energy backscattered ray intensity data of the substance to be tested inside the explosive into the first quadratic function, then the substance to be tested is a second-class substance or a third-class substance. If the value of the high-energy backscattered ray intensity data of the substance to be tested inside the explosive is greater than the value obtained by substituting the low-energy backscattered ray intensity data of the substance to be tested into the second quadratic function, then the substance to be tested is a second-category substance; if the value of the high-energy backscattered ray intensity data of the substance to be tested inside the explosive is less than the value obtained by substituting the low-energy backscattered ray intensity data of the substance to be tested into the second quadratic function, then the substance to be tested is a third-category substance.

2. The explosive material identification and imaging method based on X-ray backscattering as described in claim 1, characterized in that, The explosives include three categories: organic matter, inorganic matter, and mixtures. The corresponding high and low energy backscattering intensity data are calculated based on the mass attenuation coefficient, material density, and scattering angle of representative substances in the three categories.

3. The explosive material identification and imaging method based on X-ray backscattering as described in claim 1, characterized in that, The actual high and low energy backscatter intensity data of the material inside the explosive obtained by the high and low energy detector are discrete points located around the corresponding theoretical curve. Based on the distribution of discrete points around the corresponding theoretical curve for different types of materials, multiple division regions are obtained.

4. An explosive material identification and imaging system based on X-ray backscattering, performing the explosive material identification and imaging method based on X-ray backscattering as described in any one of claims 1 to 3, characterized in that, include: Analysis module: Based on the changes in the theoretical values ​​of high and low energy backscattering intensity corresponding to different types of substances within the explosive and their thickness, theoretical curves corresponding to different types of substances are obtained. Division module: Based on the distribution of high and low energy backscattering intensity data actually generated by different types of materials around the corresponding theoretical curves, the theoretical curve is divided into multiple regions, with each region corresponding to a type of material; Category Detection Module: Acquires high and low energy backscattered ray intensity data of the substance to be tested inside the explosive, and determines the category of the substance to be tested inside the explosive based on the division region where the acquired high and low energy backscattered ray intensity data is located.

5. The explosive material identification and imaging system based on X-ray backscattering as described in claim 4, characterized in that, In the division module, the actual high and low energy backscatter intensity data of the material inside the explosive obtained by the high and low energy detector are discrete points located around the corresponding theoretical curve. Based on the distribution of discrete points around the corresponding theoretical curve for different types of materials, multiple division regions are obtained.

6. A computer device, characterized in that, include: The computer device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the computer device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, they perform the explosive material identification and imaging method based on X-ray backscattering as described in any one of claims 1 to 3.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, performs the explosive material identification and imaging method based on X-ray backscattering as described in any one of claims 1 to 3.

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