CN204422780U - A kind of safety detection device - Google Patents

Abstract

The utility model relates to a safety detection device, comprising a CT detection device and a multi-view detection device, the CT detection device and the multi-view detection device share a detection channel; and a transmission device, the transmission device passes through the CT detection device A detection channel and a detection channel of a multi-view detection device. The superior effect of the utility model is that: the multi-view detection device is used in combination with the CT detection device, and the CT detection device is used to obtain the three-dimensional fault structure information of the detected object, which improves the detection accuracy of the detected object; at the same time, the multi-view detection device is adopted It makes up for the shortcomings of the CT detection device that the detection accuracy of the atomic number decreases in the environment of high-density metal objects, and improves the accuracy of the entire detection device while reducing equipment costs.

Description

A safety detection device

technical field

The utility model relates to the technical field of safety detection, in particular to a safety detection device.

Background technique

For the detection of explosives, the commonly used technical means in the world at this stage are roughly divided into X-ray detection technology, neutron detection technology, electromagnetic detection technology, and vapor trace detection technology. X-ray technology is currently the most widely used due to its own unique advantages. security check technology. X-ray security inspection technologies mainly include single-energy fluoroscopy technology, dual-energy fluoroscopy technology, multi-view technology, backscattering technology, single-energy spectral CT technology, dual-energy CT technology, etc. Single-energy fluoroscopy technology is the earliest X-ray security inspection technology used. It can only obtain the shape information of the object in the package, but not the material information. It has been phased out at present, but it is still used in some occasions with relatively low detection requirements. use. Dual-energy fluoroscopy technology is currently the most widely used technical means in X-ray fluoroscopy security inspection technology on the market. It obtains the high and low energy projections of objects without object occlusion by means of material stripping, and then determines the atomic number information of materials. Although the dual-energy perspective imaging technology can approximately determine the effective atomic number of the substance, it cannot obtain the density information of the object. The multi-view technology makes up for this shortcoming to a certain extent. This technology can obtain approximate dangerous goods through multi-view projection CT reconstruction. Thickness information, based on the thickness information and the projection value, can approximately determine the density of the substance. Since it is difficult to accurately reconstruct the object section from the projections under a few viewing angles, the detection error of this technology is relatively large. Due to its sensitivity to low atomic number and high-density substances, backscattering technology is mostly used to detect dangerous goods wrapped on the surface. As an important non-contact internal inspection method, X-ray computed tomography (CT, Computed Tomography) technology is playing an increasingly important role in the fields of medical diagnosis, nondestructive testing, and safety inspection. Especially in the field of security inspection, CT-type equipment is currently the only EDS (Explosive Detection System) type security inspection equipment certified by the US Transportation Security Administration (TSA, Transportation Security Administration), which shows the status of X-ray CT technology in the field of security inspection technology. Generally, X-ray CT technology can be divided into single-energy spectrum CT technology and multi-energy spectrum CT technology. Single-energy spectrum CT technology can obtain the attenuation coefficient information of substances (by converting equivalent density). This technology is simply copied from medical CT technology. However, only density information can be obtained, so it still has certain limitations. The X-ray dual-energy CT technology in the multi-energy spectral CT technology has the highest detection accuracy in the X-ray security inspection technology because it can obtain the atomic number and density information of the material at the same time, so it has received more and more attention in the security inspection. Applications. However, in terms of equipment cost, the cost of single-energy spectrum CT is significantly lower than that of multi-energy spectrum CT. In addition, even for multi-energy spectral CT, such as the most commonly used dual-energy CT, if there is a high-density metal object in the detected luggage, the resolution accuracy of its atomic number will be significantly reduced.

The Chinese patent with the publication number CN101470082A discloses an article detection device and a detection method thereof. The device includes an X-ray system and a CT system, and the information collected by the X-ray system and the information collected by the CT system are used comprehensively to identify dangerous goods. Increase the data information for judgment and improve the accuracy of judgment. The device only utilizes an X-ray system with a single viewing angle, and has a simple structure and low precision.

The international patent with the publication number EP2676128A2 discloses a multi-scanner system and method. The system includes a CT device and a multi-energy scanner. During detection, the object first passes through the CT device, and the tomographic information of the CT and the subsequent multi-scanner are used to detect the object. The information obtained by the scanner can be combined to identify dangerous goods. This device is not a detection mode that combines CT and multi-view equipment.

Utility model content

The purpose of the utility model is to overcome the deficiencies in the prior art and provide a high-precision safety detection device.

The utility model is achieved through the following technical solutions:

A safety detection device, comprising a CT detection device and a multi-view detection device arranged on one side of the CT detection device, the CT detection device and the multi-view detection device share a detection channel;

The CT detection device is connected with the first control and data processing computer; the multi-view detection device is equipped with a multi-view detector and a ray source module, and the multi-view detector is connected with the second control and data processing computer; the The first control and data processing computer, the second control and data processing computer are all connected to the comprehensive data processing computer;

The safety detection device also includes a transmission device, and the transmission device passes through the detection channel of the CT detection device and the detection channel of the multi-view detection device.

The technical solution is preferably that the CT detection device includes a CT ray source module, a CT gantry, and a CT detector, and the CT ray source module and the CT detector are both arranged on the CT gantry.

The technical solution is preferably that the CT detection device adopts one of a single-energy spectrum CT detection device and a multi-energy spectrum CT detection device.

The technical solution is preferably that the channel diameter of the CT detection device is 80cm-120cm.

The technical solution is preferably that the CT detector adopts one of a single-layer detector, a double-interlayer detector, and a photon counting detector.

In the technical solution, preferably, the number of viewing angles of the multi-view detection device is 2-4.

The technical solution is preferably that the multi-view detector adopts one of a single-layer detector, a double-interlayer detector, and a photon-counting detector.

The utility model provides a safety detection method, which at least includes the following steps:

a: Place the detected object on the running transmission device, the detected object passes through the CT detection device, and the first control and data processing computer obtains the three-dimensional tomographic structure information, density information and atomic number information of the detected object , obtain the region of interest of the detected object according to the density information and the atomic number information;

b: The detected object passes through the multi-view detection device, and the second control and data processing computer obtains the perspective image information of multiple viewing angles of the detected object; at the same time, combined with the three-dimensional tomographic structure information in step a, the image of the region of interest is obtained Effective atomic number information; or correct the atomic number information through the atomic number correction method to obtain effective atomic number information;

c: The comprehensive data processing computer obtains the density information and effective atomic number information of the detected object, and determines whether to give an alarm message by searching the database.

The utility model also provides a safety detection method, which at least includes the following steps:

a: placing the detected object on the running transmission device, the detected object passes through the multi-view detection device, and the second control and data processing computer obtains perspective image information and atomic number information of multiple viewing angles of the detected object, Obtain the region of interest of the detected object according to the perspective image information and atomic number information of multiple viewing angles of the detected object;

b: The detected object passes through the CT detection device, and the first control and data processing computer obtains the three-dimensional tomographic structure information, density information and atomic number information of the detected object; at the same time, it combines the perspective image information and atomic number information in step a Ordinal number information to obtain effective atomic number information of the region of interest; or correct atomic number information by atomic number correction method to obtain effective atomic number information;

c: The comprehensive data processing computer obtains the density information and effective atomic number information of the detected object, and determines whether to give an alarm message by searching the database.

Preferably, the technical solution is that the CT detection device adopts a single-energy spectrum CT detection device, and the atomic number information is corrected by an atomic number correction method, including the following steps:

1) Obtain the region of interest according to the three-dimensional tomographic structure information of the detected object, and analyze the degree of object overlap at each projection angle of view of the region of interest along the ray projection direction, and obtain the parameters of the degree of object overlap at each angle of view;

2) When the multi-view detection device obtains 2-4 perspective projection viewing angles, select the object overlapping degree parameter to calculate the effective atomic number;

The CT detection device adopts a multi-energy spectrum CT detection device, and corrects the atomic number information through an atomic number correction method, including the following steps:

1) Obtain the region of interest according to the three-dimensional tomographic structure information of the detected object, and analyze the degree of overlapping of the region of interest with the metal object at each projection angle of view along the ray projection direction, and obtain the overlapping degree parameters of the metal object at each angle of view;

2) When the multi-angle detection device obtains 2-4 perspective projection angles of view, the parameter of overlapping degree of metal objects is selected to calculate the effective atomic number.

Preferably, the technical solution is that the method for calculating the parameter of the overlapping degree of objects includes: normalizing the projection grayscale curve, treating it as a probability density function of position information, and calculating the mean square error under the probability density function, As the value of the object overlap degree parameter; the larger the value, the lower the object overlap degree, and vice versa; or locate the region of interest of the detected object, set the value of the image in the region of interest to 0, and then follow Orthographic projection is performed on the multi-view angle directions and imaging geometric parameters to obtain the projected gray curve of the object after removing the region of interest, and calculate the mean value of the projection data corresponding to the projection position of the region of interest as the overlap degree parameter. The smaller the mean value, the smaller the degree of object overlap.

The described technical solution is preferably that the calculation method of the metal object overlapping parameter includes: locating the region of interest of the detected object and determining the metal region inside it by setting a threshold value, and passing through the region of interest and outside the metal region The image in the metal area is set to 0, and the image in the metal area is set to 1, and then the forward projection is performed according to the viewing angle direction of the multi-view angle and the imaging geometric parameters, and the projected gray curve of the object after the region of interest is removed is obtained, and the sensitivity is calculated. The mean value of the projection data corresponding to the projection position of the region of interest is used as the parameter of the degree of overlap. The smaller the mean value, the smaller the degree of object overlap.

The technical solution is preferably that the density of the region of interest is 1.2-1.5 g/cm3, and the atomic number is 6-8.

Compared with the prior art, the utility model has the superior effect that: the multi-view detection device is used in combination with the CT detection device, and the CT detection device is used to obtain the three-dimensional tomographic structure information of the detected object, which improves the detection accuracy of the detected object ; At the same time, the multi-view detection device is used to make up for the shortcomings of the CT detection device for the decrease in the detection accuracy of the atomic number in the environment of high-density metal objects, and to improve the accuracy of the entire detection device while reducing equipment costs.

Description of drawings

Fig. 1 is a structural schematic diagram of the first embodiment of the safety detection device described in the present invention;

Fig. 2 is the detection flowchart of the device described in Fig. 1 adopting the dual-energy spectrum CT detection device first and then the multi-view detection device;

Fig. 3 is a schematic structural diagram of the second embodiment of the safety detection device described in the present invention;

Fig. 4 is the detection flowchart of the device described in Fig. 3 adopting the multi-view detection device first and then the dual-energy spectrum CT detection device;

Fig. 5 is a flow chart of the safety detection device first passing through the single-energy spectrum CT detection device and then passing through the multi-view detection device;

Fig. 6 is a flow chart of the safety detection device first passing through the multi-view detection device and then the single-energy spectrum CT detection device;

Fig. 7 is a flow chart of the effective atomic number calculation method when the CT detection device adopts a single energy spectrum CT detection device;

Fig. 8 is a flow chart of the effective atomic number calculation method when the CT detection device adopts a dual-energy spectrum CT detection device and there is a high-density metal in the region of interest;

Fig. 9 is a schematic flow chart of a calculation method of an object overlapping degree parameter;

Fig. 10 is a schematic flow chart of the second calculation method of the object overlapping degree parameter;

FIG. 11 is a schematic flow chart of a calculation method for a parameter of an overlapping degree of a high-density metal object.

The accompanying drawings are marked as follows:

1-CT ray source module, 2-CT frame, 3-CT detector, 4-first detector, 5-second detector, 6-second ray source, 7-third detector, 8-th Three ray sources, 9-object to be detected, 10-first control and data processing computer, 11-first ray source, 12-comprehensive data processing computer, 13-second control and data processing computer, 14-fourth detector , 15-the fourth ray source, 16-transmission device.

Detailed ways

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described in further detail.

Example 1

As shown in Figure 1, the safety detection device of the present invention includes a CT detection device and a multi-view detection device arranged on one side of the CT detection device, and the CT detection device and the multi-view detection device share a detection channel. The CT detection device is connected to a first control and data processing computer 10; a multi-view detector and a ray source module are arranged inside the multi-view detection device, and the multi-view detector is connected to a second control and data processing computer 13; The first control and data processing computer 10 and the second control and data processing computer 13 are all connected to the comprehensive data processing computer 12 for data interaction. The safety detection device also includes a transmission device 16, and the transmission device 16 sequentially passes through the detection channel of the CT detection device and the detection channel of the multi-view detection device. The CT detection device includes a CT ray source module 1, a CT frame 2, and a CT detector 3, the CT frame 2 is in the shape of a ring, and the CT ray source module 1 and the CT detector 3 are arranged on the CT frame 2 on.

Further, the multi-view detector includes a first detector 4, a second detector 5, a third detector 7, and a fourth detector 14, and the radiation source module includes a first radiation source 11, a second radiation source 6. The third ray source 8 and the fourth ray source 15 . The utility model sets the first detector 4, the second detector 5, the third detector 7, the fourth detector 14, the first ray source 11, the second ray source 6, the third ray source 8, the fourth ray The source 15 forms a safety detection device combining a CT detection device and a four-view detection device.

Wherein, the fourth detector 14 and the fourth ray source 15 form a V1 viewing angle, the third detector 7 and the third ray source 8 form a V2 viewing angle, and the second detector 5 and the second ray source 6 form a V1 viewing angle. V3 viewing angle, the first detector 4 and the first ray source 11 form a V4 viewing angle.

When the safety detection device described in the utility model is applied, firstly, the detected object 9 is placed on the transmission device 16, and the safety detection device is started, and the transmission device 16 travels to the right at a constant speed, and the detected object 9 is transported to the detection channel Middle; when the detected object 9 reaches the CT detection device, the CT gantry 2 rotates at a constant speed; the detected object 9 triggers the CT ray source module 1, and the CT ray source module 1 emits an X-ray beam to penetrate the detected object 9, and the The CT detector 3 receives the corresponding attenuation signal transmitted through the detected object 9; the CT gantry 2 continuously rotates, and the detected object 9 moves synchronously and uniformly with the transmission device 16; at the same time, the CT detector 3 continues to receive different The angle X-ray beam transmits the attenuated signal data of the detected object 9, and transmits the received data into the first control and data processing computer 10, and the first control and data processing computer 10 performs CT reconstruction of each tomographic data and data processing.

When the detected object 9 leaves the CT detection device and enters the multi-view detection device, the detected object 9 sequentially triggers the first ray source 11, the second ray source 6, the third ray source 8, and the fourth ray source 15. The source sequentially emits X-ray beams to transmit the detected object 9; the first detector 4, the second detector 5, the third detector 7, and the fourth detector 14 respectively receive the corresponding attenuation transmitted through the detected object 9 signal, and transmit the attenuated signal to the second control and data processing computer 13 to form corresponding projection image signals of V4, V3, V2, and V1 perspectives.

The first control and data processing computer 10 and the second control and data processing computer 13 transmit the received signal to the comprehensive data processing computer 12, and after data processing by the comprehensive data processing computer 12, the final detection result is obtained.

Further, a collimator (not shown) is arranged on the side where the first ray source 11, the second ray source 6, the third ray source 8, and the fourth ray source 15 emit X-rays, and the X-rays pass through After the collimator becomes a thin fan beam. The collimator is prior art.

As shown in FIG. 2 , the detection flow chart of the safety detection device of the present invention firstly passes through the dual-energy spectrum CT detection device and then passes through the multi-view detection device. S11 completes the collection of CT data, S12 performs data reconstruction, and obtains the tomographic structure information, tomographic electron density information and tomographic effective atomic number information of the detected object 9; S13 performs regional segmentation on each tomographic CT image to obtain each independent Connected regions; in S14, analyze the electron density and effective atomic number of each independently connected region, query the database, and preliminarily determine the three-dimensional region of interest; S15 carries out data acquisition of the multi-view detection device, and in S16, the image information obtained in S15 is processed Segmentation to obtain a two-dimensional region of interest, combined with the CT tomographic information in S14; in S17, correct the effective atomic number of the three-dimensional region of interest, and obtain the corrected effective atomic number information of each three-dimensional region of interest; finally in S18 For the connected regions of each three-dimensional region of interest, using the electron density information obtained in S14 and the corrected effective atomic number information obtained in S17, the detection results are given by querying the database, and the detection results are displayed in the comprehensive data processing computer 12, and decide whether to report to the police.

Example 2

As shown in Figure 3, the safety detection device described in the present invention provides another embodiment, the difference from Embodiment 1 is that the detected object 9 is placed on the transmission device 16, and the transmission device 16 travels to the left, The detected object 16 first passes through the multi-view detection device, and then passes through the CT detection device. FIG. 4 is a flowchart of the work of the safety detection device shown in FIG. 3 . The CT detection device adopts a dual-energy spectrum CT detection device, and the specific process includes: completing multi-view X-ray data acquisition in S21; completing image segmentation in S22, and querying the database according to the effective atomic number information of each segmented area, and initially determining Each two-dimensional region of interest; CT data acquisition is completed in S23, and three-dimensional reconstruction is performed on the collected CT data in S24 to obtain the structural information, electron density information and effective atomic number information of each CT slice; in S25, according to the information in S22 Two-dimensional region of interest, region segmentation is performed on each tomographic CT image information, and a three-dimensional connected region of interest corresponding to a multi-view two-dimensional region of interest is obtained; in S26, refer to the two-dimensional region of interest information in S22, and the three-dimensional sensing Correct the effective atomic number of the region of interest to obtain the corrected effective atomic number information of each three-dimensional region of interest; finally, in S27, for each three-dimensional region of interest, according to the electron density information obtained in S24 and the corrected effective atomic number obtained in S26 For ordinal information, the detection result is given by querying the database, and the detection result is displayed on the comprehensive data processing computer 12, and whether to call the police is determined.

Example 3

As shown in Figure 5, the safety detection device of the present invention also provides another embodiment. The difference between this embodiment and Embodiment 1 is that the CT detection device adopts a single energy spectrum CT detection device. The safety detection device adopts a detection method that first passes through the single-energy spectrum CT detection device and then passes through the multi-view detection device; specifically includes: S31 completes the collection of CT data, performs CT three-dimensional reconstruction in S32, and obtains fault structure information and fault electron density information , S33 performs region segmentation on each tomographic CT image to obtain each independent connected region in the tomography, S34 refers to the electron density information, and preliminarily determines the three-dimensional region of interest by querying the database; in S35, the multi-view X-ray image is completed by the multi-view detection device Information collection; in S36, the image in S35 is segmented to obtain the corresponding two-dimensional region of interest. At the same time, combined with the CT tomographic information in S34, the effective atomic number of the three-dimensional region of interest is finally calculated in S37 to obtain each three-dimensional region of interest. The effective atomic number information of the region of interest; in S38, for each three-dimensional connected region of interest, and using the electron density information obtained in S34 and the effective atomic number information obtained in S37, the detection result is given by querying the database, and The detection result is displayed on the integrated data processing computer 12, and it is decided whether to alarm.

Example 4

As shown in Figure 6, the safety detection device of the present invention also provides another embodiment. The difference between this embodiment and Embodiment 2 is that the CT detection device adopts a single energy spectrum CT detection device. The safety detection device adopts a detection method that first passes through the multi-view detection device and then passes through the single-energy spectrum CT detection device; specifically includes: S41 The multi-view detection device collects image data of the detected object 9, S42 divides the collected image information, And according to the effective atomic number information of each segmented area, query the database, preliminarily determine each two-dimensional area of interest, S43 collect data on the detected object 9, and obtain the CT tomographic structure information and tomographic electron density of the detected object 9 in S44 information, S45 performs region segmentation on each tomographic CT image according to the two-dimensional region of interest determined in S42, and obtains each three-dimensional connected region of interest corresponding to the multi-view two-dimensional region of interest, and then combines the results of S42 in S46 , calculate the effective atomic number of the three-dimensional region of interest, and obtain the effective atomic number information of each three-dimensional region of interest; ordinal information, query the database, give the detection result, and display the detection result on the comprehensive data processing computer 12, and decide whether to call the police.

Accompanying drawings 7 and 8 of the safety detection device described in the utility model provide the calculation method of the effective atomic number. Further, in FIG. Correct the ordinal information, obtain the region of interest according to the three-dimensional fault structure information of the detected object, and analyze the degree of object overlap of each projection angle of view in the region of interest along the ray projection direction, and obtain the parameters of the degree of object overlap at each angle of view; When the angle of view detection device obtains 2-4 perspective projection angles of view, the angle of view with the smallest parameter of the overlapping degree of objects is selected to calculate the effective atomic number. In Fig. 8, the CT detection device adopts a multi-energy spectrum CT detection device, and the atomic number information is corrected by the atomic number correction method, and the region of interest is obtained according to the three-dimensional tomographic structure information of the detected object, and the interest region is analyzed. The degree of overlap between the region of interest and the metal object at each projection angle of view along the ray projection direction, and obtain the overlapping degree parameter of the metal object at each angle of view; when the multi-angle detection device obtains 2-4 perspective projection angles of view, select the overlap degree of the metal object The angle of view with the smallest parameter is used to calculate the effective atomic number.

As shown in accompanying drawings 9, 10, and 11, the calculation method of the object overlapping degree parameter is provided. Further, in Fig. 9, the calculation method of the object overlapping degree parameter includes normalizing the projected grayscale curve, and As the probability density function of the position information, the mean square error under the probability density function is calculated as the value of the object overlapping degree parameter; the larger the value, the lower the object overlapping degree, and vice versa. Figure 10 shows another calculation method for the parameters of the overlapping degree of the object, locate the region of interest of the detected object, set the value of the image in the region of interest to 0, and then according to the viewing angle direction and imaging geometry of the multi-view The parameters are forward projected to obtain the projected gray curve of the object after removing the region of interest, and the mean value of the projection data corresponding to the projection position of the region of interest is calculated as the overlap degree parameter. The smaller the mean value, the smaller the degree of object overlap. The calculation method of the overlapping parameters of the metal object is shown in Fig. 11, including: locating the region of interest of the detected object and determining the metal region inside it by setting a threshold value, through the images in the region of interest and outside the metal region Set it to 0, set the image in the metal area to 1, and then perform forward projection according to the viewing angle direction of the multi-view angle and the imaging geometric parameters to obtain the projected gray curve of the object after removing the region of interest, and calculate the region of interest The mean value of the projection data corresponding to the projection position is used as the overlap degree parameter. The smaller the mean value, the smaller the degree of object overlap.

The multi-view detectors and ray source modules described in the utility model are all existing technologies, that is, ordinary detectors and ray source modules, and the number of multi-view detectors and ray source modules is combined according to actual needs, which can form Combined safety detection device of CT detection device and three-view detection device, combined safety detection device of CT detection device and double-view detection device. In addition, the CT detection device, multi-view detection device, first control and data processing computer 10, comprehensive data processing computer 12, and second control and data processing computer 13 are also existing technologies, and operators can choose according to actual conditions.

The utility model is not limited to the above-mentioned embodiments. Without departing from the essential content of the utility model, any deformation, improvement and replacement conceivable by those skilled in the art all fall within the scope of the utility model.

Claims (7)

1. A safety detection device, characterized in that it comprises a CT detection device and a multi-view detection device arranged on one side of the CT detection device, and the CT detection device and the multi-view detection device share a detection channel; The CT detection device is connected with the first control and data processing computer; the multi-view detection device is equipped with a multi-view detector and a ray source module, and the multi-view detector is connected with the second control and data processing computer; the The first control and data processing computer, the second control and data processing computer are all connected to the integrated data processing computer; The safety detection device also includes a transmission device, and the transmission device passes through the detection channel of the CT detection device and the detection channel of the multi-view detection device. 2. The safety detection device according to claim 1, wherein the CT detection device comprises a CT ray source module, a CT frame, and a CT detector, and the CT ray source module and the CT detector are all arranged on the CT rack. 3. The safety detection device according to claim 1, wherein the multi-view detector is one of a single-layer detector, a double-layer detector, and a photon counting detector. 4. The security detection device according to claim 1, characterized in that, the number of viewing angles of the multi-view detection device is 2-4. 5. The safety detection device according to claim 1 or 2, wherein the CT detection device adopts one of a single-energy spectrum CT detection device and a multi-energy spectrum CT detection device. 6. The safety detection device according to claim 1 or 2, characterized in that, the channel diameter of the CT detection device is 80cm-120cm. 7. The safety detection device according to claim 2, wherein the CT detector is one of a single-layer detector, a double-layer detector, and a photon counting detector.