HK1128961A - Device and method for inspecting contraband in aviation cargo container - Google Patents

Description

Device and method for checking contraband in air freight container

Technical Field

The invention relates to the field of cargo security inspection, in particular to a device and a method for inspecting contraband in air cargo.

Background

The main inspection methods in the field of inspection of air cargo (such as air containers) are manual inspection and transmission of X-ray machine (only small air containers). There are also devices for inspection of goods using CT (computed tomography) technology, such as the products of smith corporation (which uses an X-ray machine) and the washingx corporation (which uses a radioactive source). Because of the low penetration of the X-ray machine, the strict control of the radiation source on the use management makes the two products have many limitations on use. In particular, these apparatuses perform CT imaging inspection by using horizontal pass-through scanning, i.e., the object to be inspected passes horizontally, and the scanning system rotates around the passing path of the object to be inspected, which makes the cargo throughput of these CT inspection systems low. Moreover, such CT inspection systems are severely limited in structural size and penetration capability and therefore are not capable of inspecting larger sized air containers. For example, none of the existing devices is capable of inspecting air containers that are more than 2 meters in length and width. Furthermore, the horizontal pass-through scanning system requires equal floor space on both the left and right sides of the cargo passage, and thus occupies a large space.

In addition, various radiation imaging methods, such as fluoroscopy, multi-view imaging, and CT imaging, have been proposed in the prior art, and these different imaging methods generally correspond to different scanning methods of the cargo by the scanning system. The above-described conventional inspection apparatuses generally implement only one of the scanning modes, thereby limiting the selection of the imaging mode. However, different scanning imaging modes are sometimes required to be carried out on the same cargo in the cargo inspection process, and the existing inspection device cannot meet the requirement.

Disclosure of Invention

The object of the present invention is to solve at least one of the above-mentioned drawbacks of the prior art.

In order to achieve the above object, the present invention provides an apparatus for inspecting contraband in an air cargo container, comprising:

the rotary table is positioned at the object detection position and used for bearing the object to be detected and driving the object to be detected to rotate;

an object conveying system for conveying the object to be inspected onto the turntable in a horizontal direction and conveying the object to be inspected away from the turntable after the inspection is completed;

the scanning system is arranged around the rotary table and used for scanning the detected object and acquiring imaging data, and comprises a radiation source and a detector which can synchronously move along the vertical direction;

a turntable driving/controlling subsystem which drives and controls the rotation of the turntable so that the turntable can be continuously rotated about its rotation axis or rotated to any predetermined angular position;

a scanning drive/control subsystem that drives and controls the synchronous movement of the radiation source and the detector in the vertical direction so that the radiation source and the detector can be moved continuously in the vertical direction or to any predetermined vertical position;

and the main control computer provides a human-computer interaction interface so as to control the work of the device according to the instruction of an operator, and images and displays according to the imaging data.

In the apparatus of the present invention, the turntable can be continuously rotated or rotated to any predetermined angular position, and the scanning system (including the radiation source and the detector) can be continuously moved in the vertical direction or moved to any predetermined vertical position. Through the combination of different movement modes of the turntable and the scanning system, the device can scan the detected object in multiple scanning modes, an operator can select one or more scanning modes to scan the detected object according to actual conditions, and then the detected object is imaged in different modes by matching with corresponding algorithms, so that different requirements are met. Therefore, the device of the invention is a multifunctional comprehensive inspection system.

Drawings

FIG. 1 is a side view of an embodiment of the apparatus of the present invention.

Fig. 2 is a top view of the device in the embodiment of fig. 1.

Fig. 3 is a left side view of the device in the embodiment of fig. 1.

Detailed Description

Referring to fig. 1-3, one embodiment of the apparatus for inspecting contraband in an air cargo container of the present invention is shown. As shown, the apparatus includes a turntable 11, which is located at an object detection position, and is used for carrying an object to be detected (not shown), such as an air container, and driving the object to be detected to rotate. The apparatus further includes an object conveying system (not shown) for conveying the object to be inspected onto the turntable in a horizontal direction and away from the turntable after the inspection is completed, as is well known to those skilled in the art. The object conveying system and the turntable together may be referred to as a conveying system. The turntable 11 is in the transport path of the object transport system. In one embodiment, the turntable 11 is a compound rotary transfer table. Such a compound carousel is described in the applicant's chinese patent application No.200610169797.3, which is incorporated herein by reference in its entirety. The composite rotary worktable can convey the detected object through the scanning channel and can also support and drive the detected object to rotate in the scanning channel. In this way, when the object to be inspected is to be rotationally scanned, the scanning system (described in detail below) is allowed to rotate not around the object to be inspected but by the object to be inspected itself.

The apparatus also includes a turntable drive/control subsystem (not shown) for the turntable that drives and controls the rotation of the turntable so that the turntable can be rotated continuously or to any predetermined angular position about its axis of rotation. The turntable drive/control subsystem typically includes a motor and a servo controller for the motor.

The apparatus also includes a scanning system disposed about the turntable for scanning the inspected object and acquiring imaging data. As shown in the figure, the scanning system comprises a radiation source 6 and a detector 17 which are arranged at two sides of a rotary table 11, the radiation source 6 and the detector 17 can move synchronously along the vertical direction, and a horizontal ray plane 16 from the radiation source 6 and a plane where the detector 17 is located are always on the same horizontal plane. The radiation source 6 emits controllable X-rays or gamma rays, and may be a linear electron accelerator, an isotope source, or an X-ray machine. The detector 17 is responsible for converting the ray passing through the detected object into an electric signal, and can be a solid detector or a gas detector; the structure may be formed using one or more linear or arcuate arrays, and may also be formed using high and low energy detectors. The scanning system also comprises a data acquisition unit which is responsible for converting the electric signals of the detector into digital signals and transmitting the digital signals to a main control computer through a bus or Ethernet. The detector 17 itself may carry the data collector.

The scanning system further comprises a radiation source mounting structure for mounting the radiation source 6 and a detector mounting structure for mounting the detector 17, which are arranged on both sides of the turntable 11. The radiation source mounting structure or the detector mounting structure includes one or more column assemblies. In one embodiment, the radiation source mounting structure and the detector mounting structure each include one or more column assemblies. In one embodiment, each post assembly has a substantially identical structure. In fig. 1-3, the radiation source mounting structure preferably comprises a single column assembly, while the detector mounting structure preferably comprises two column assemblies, thereby forming a scanning architecture in the form of a three-column. The three-column structure reduces the occupied area to the maximum extent under the condition of ensuring the stable installation of the detector and the radiation source. In addition, in order to further reduce the floor space, the detectors arranged on the two column assemblies are preferably planar detector arrays, and the floor space of the planar detector arrays is smaller than that of the curved detector arrays.

In fig. 1 to 3, the pillar assembly includes a pillar 8, 1 or 10 disposed in a vertical direction. Wherein, for the radiation source mounting structure, the upright post assembly comprises an upright post 8; for the detector mounting structure, two column assemblies are provided, including column 1 and column 10. On each column, a lifting mechanism is provided along the extension direction of the column, the lifting mechanism is supported by the column, and the radiation source or the detector is mounted on the lifting mechanism. The lifting mechanism comprises a roller screw 12 and a lifting platform 7, 2 or 9 arranged along the column, wherein in fig. 1 to 3, the lifting platform in one column assembly of the radiation source mounting structure is denoted by reference numeral 7, and the lifting platforms in two column assemblies of the detector mounting structure are denoted by reference numerals 2 and 9, respectively. The lifting platform 7, 2 or 9 is mounted on the threaded spindle 12 and is in threaded connection therewith, on which the radiation source 6 or the detector 17 is correspondingly fixedly mounted. In this way, when the screw 12 is rotated, the lifting platform 7, 2 or 9 can be moved up and down along the screw by interaction with the thread of the screw. In one embodiment, the lifting platform may be threadably connected to the lead screw via a nut, wherein the nut is threadably connected to the lead screw, and wherein the lifting platform is fixedly connected to the nut. In another embodiment, the lift platform itself may include a threaded passage therethrough that is threadably connected to the lead screw. The lifting mechanism may further comprise at least one guide rail disposed along the upright, along which the lifting platform is slidable to guide the lifting movement of the lifting platform. As shown, the lifting mechanism preferably includes two guide rails 13 disposed on either side of the lead screw 12. In one embodiment, the lifting platform is slidably coupled to the rail via a slider, wherein the slider is slidably coupled to the rail and the lifting platform is fixedly coupled to the slider. In another embodiment, the lift platform may include a channel therethrough through which the rail extends.

When the detector mounting structure or the radiation source mounting structure includes a plurality of column assemblies, the mounting structure may further include a connection beam connected between each pair of adjacent columns in order to achieve structural stability between the column assemblies. As shown in fig. 1 to 3, in the probe mounting structure, a connection beam 3 is connected between columns 1 and 10.

When the detector mounting structure comprises a plurality of column assemblies, the mounting structure may further comprise a cross beam connected between each pair of adjacent lifting platforms, wherein the detector (preferably a planar detector array) is fixedly mounted on the cross beam and via the cross beam is fixedly mounted to the lifting platforms. As shown in fig. 1 to 3, in the probe mounting structure, a cross beam 4 is connected between the elevating platforms 2 and 9, and a probe 17 is connected to the cross beam 4. Due to the rigid characteristic of the mechanical structure, in order to reduce the requirements on the manufacturing precision, particularly the installation precision of the rigid structure, the detector beam 4 adopts an installation mode that one end is fixedly hinged and the other end is elastically connected to connect the two ends of the beam 4 to the connection points of the detector lifting platforms 2 and 9 respectively. So that the detector beam 4 can normally run synchronously during the scanning operation.

Also included in the apparatus of the present invention is a scan drive/control subsystem that drives and controls the synchronized movement of the radiation source and the detector in the vertical direction so that the radiation source and the detector can be moved continuously in the vertical direction or to any predetermined vertical position. The scanning driving/controlling subsystem comprises a servo driving motor 5, a driving motor and a driving control system, wherein the servo driving motor is used for driving a lead screw 12 in each upright post component; and a servo synchronization controller (not shown) for controlling the synchronous operation of the respective servo drive motors 5. When the device of the invention is a three-column structure, the servo synchronous controller is a three-axis servo synchronous controller.

The apparatus of the present invention may also include a master control computer. The control portions in the turntable drive/control subsystem and the scan drive/control subsystem may be implemented by a single control system, which may be implemented by the host computer and dedicated software in the host computer, for example. The active computer may also provide a human-computer interface to control the operation of the device according to operator instructions and to image and display based on the imaging data. For example, the operator may input parameters such as the continuous rotation angle or predetermined angular position of the turntable, the continuous movement length or predetermined vertical position of the radiation source and detector, etc. to the turntable drive/control subsystem and the scanning drive/control subsystem via the human-machine interface. Thus, the operator can control the device to scan the detected object in different modes. Moreover, the main control computer can utilize the imaging data obtained by the scanning system to carry out imaging according to a certain data processing algorithm.

As described above, the apparatus of the present invention can inspect an object to be inspected in a plurality of operation modes. These modes may include, for example:

(1) the device comprises a perspective plane imaging mode, a rotary table, a radiation source, a detector and a two-dimensional imaging device, wherein the rotary table drives a detected object to at least one preset angle position, when the detected object is located at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device respectively forms two-dimensional perspective images of the detected object at each preset angle position according to the perspective image data at each preset angle position;

(2) the device comprises a multi-view three-dimensional imaging mode, a turntable, a radiation source, a detector and a three-dimensional imaging device, wherein the turntable drives the detected object to a plurality of preset angle positions, when the detected object is positioned at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device reconstructs a three-dimensional image of the detected object according to the perspective image data at each preset angle position; the algorithm used in the multi-view three-dimensional imaging mode can be found in, for example, chinese patent application No.200610076574.2 of the present applicant, which is incorporated herein by reference in its entirety.

(3) A CT plane (slice or fault) imaging mode, wherein the radiation source and the detector are positioned at least one preset vertical position, when the radiation source and the detector are positioned at each preset vertical position, the rotary table drives the detected object to continuously rotate to obtain CT projection data at each preset vertical position, and the device respectively reconstructs a two-dimensional fault image of the detected object at each preset vertical position according to the CT projection data at each preset vertical position;

(4) the device comprises a CT spiral scanning imaging mode, wherein the radiation source and the detector move from a first preset vertical position to a second preset vertical position along the vertical direction, meanwhile, the rotary table drives the detected object to rotate continuously, so that spiral scanning is carried out on the detected object, CT spiral scanning projection data of the detected object between the first preset vertical position and the second preset vertical position are obtained, and a three-dimensional tomographic (body data) image of the detected object between the first preset vertical position and the second preset vertical position is reconstructed by the device according to the CT spiral scanning projection data.

These modes above are exemplary only and not exhaustive. It is noted that the turntable may be continuously rotated or pivoted to any predetermined angular position, while the scanning system (including the radiation source and the detector) may be continuously moved or moved in a vertical direction to any predetermined vertical position. The skilled person can study the different combinations of the movement patterns of the turntable and the scanning system in the device according to the invention to obtain the various possible modes of operation of the device according to the invention. The operator may select one or more of various possible modes of operation to inspect the inspected object.

The device of the invention can be used for rapidly detecting large and medium goods such as standard-sized air containers and the like, and providing radiation images such as perspective plane images, CT slice plane images and three-dimensional data images (by using a multi-view imaging method or a spiral CT method) which reflect the shapes and density distribution of the goods in the air containers. The inspectors can finally and quickly judge whether the goods are consistent with the declaration and whether the goods have contraband goods or not by analyzing the characteristic information of the detected object provided by the device, thereby realizing accurate and effective safety inspection.

An exemplary operation of the device of the invention is described below:

in step (1), the object to be inspected is transferred to a turntable 11.

In steps (2) to (4), the device of the present invention is used to inspect the object in a perspective planar imaging mode.

And (2) the rotary table 11 is static, the radiation source 6 and the detector 17 synchronously perform one scanning in the vertical direction, and perspective image data of the detected object at the current angular position is obtained.

And (3) rotating the rotary table 11 by 90 degrees, and repeatedly executing the step (2) once to obtain another perspective image data.

And (4) displaying the perspective images in the steps (2) and (3) on a computer screen, and analyzing by an operator through the two perspective images, such as finding a suspicious area, and then turning to the step (8).

In steps (5) to (7), the device of the invention is used for inspecting the object to be inspected in a multi-view three-dimensional imaging mode.

And (5) rotating the turntable 11 by a small angle, for example, an angle between 10 and 30 degrees, and repeatedly executing the step (2) once.

And (6) repeating the step (5) for ten times.

And (7) reconstructing a three-dimensional image of the object through data processing according to the 12 pieces of perspective image data obtained in the step (7), and if a suspected area is found, turning to the step (8), otherwise, detecting the object.

In step (8), the suspect region is scanned in a CT plane (slice or slice) imaging mode or a CT helical scan imaging mode using the apparatus of the present invention. Specifically, the radiation source 6 and the detector 17 are positioned to the height of the suspected area, and the turntable 11 drives the object to rotate continuously. For the CT plane (slice or tomographic) imaging mode, the radiation source 6 and the detector 17 are kept stationary, CT projection data of the current position are acquired, and a two-dimensional tomographic image is reconstructed by data processing. For the CT helical scan imaging mode, the radiation source 6 and the detector 17 scan in the vertical direction within the range of the suspected region along the vertical direction, so as to obtain CT projection data of the suspected region, and reconstruct a three-dimensional tomographic volume data image through data processing.

And (9) giving final judgment by the operator through the tomography image.

Claims (24)

1. An apparatus for inspecting contraband in an air cargo container, comprising:

the rotary table is positioned at the object detection position and used for bearing the object to be detected and driving the object to be detected to rotate;

an object conveying system for conveying the object to be inspected onto the turntable in a horizontal direction and conveying the object to be inspected away from the turntable after the inspection is completed;

the scanning system is arranged around the rotary table and used for scanning the detected object and acquiring imaging data, and comprises a radiation source and a detector which can synchronously move along the vertical direction;

a turntable driving/controlling subsystem which drives and controls the rotation of the turntable so that the turntable can be continuously rotated about its rotation axis or rotated to any predetermined angular position;

a scan drive/control subsystem that drives and controls the synchronized movement of the radiation source and detector in the vertical direction such that the radiation source and detector can be moved continuously in the vertical direction or to any predetermined vertical position.

2. The apparatus of claim 1, wherein the apparatus is configured to inspect the same inspected object in at least one of a plurality of operating modes.

3. The apparatus of claim 1, wherein the apparatus is configured to inspect the same inspected object in at least two of a plurality of operating modes.

4. The apparatus of claim 2 or 3, wherein at least one of the plurality of operating modes is selected from:

the device comprises a perspective plane imaging mode, a rotary table, a radiation source, a detector and a device, wherein the rotary table drives the detected object to at least one preset angle position, when the detected object is located at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device respectively forms two-dimensional perspective images of the detected object at each preset angle position according to the perspective image data at each preset angle position;

the device comprises a multi-view three-dimensional imaging mode, a rotating table, a radiation source, a detector and a device, wherein the rotating table drives the detected object to a plurality of preset angle positions, when the detected object is located at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device reconstructs a three-dimensional image of the detected object according to the perspective image data at each preset angle position;

the device comprises a CT plane imaging mode, wherein the radiation source and the detector are positioned at least one preset vertical position, when the radiation source and the detector are positioned at each preset vertical position, the rotary table drives the detected object to continuously rotate to obtain CT projection data at each preset vertical position, and the device respectively reconstructs a two-dimensional tomographic image of the detected object at each preset vertical position according to the CT projection data at each preset vertical position; and

the device comprises a radiation source, a detector, a rotary table, a CT spiral scanning projection data and a CT spiral scanning imaging mode, wherein the radiation source and the detector vertically move from a first preset vertical position to a second preset vertical position, the rotary table drives the detected object to continuously rotate, so that the detected object is spirally scanned, the CT spiral scanning projection data of the detected object between the first preset vertical position and the second preset vertical position are obtained, and the device reconstructs a three-dimensional tomographic body data image of the detected object between the first preset vertical position and the second preset vertical position according to the CT spiral scanning projection data.

5. The apparatus of claim 1, wherein the turntable is a compound rotary transfer table.

6. The apparatus of claim 1, wherein the scanning system further comprises a radiation source mounting structure for mounting the radiation source and a detector mounting structure for mounting the detector.

7. The apparatus of claim 6, wherein the radiation source mounting structure or the detector mounting structure comprises at least one column assembly; or

The radiation source mounting structure and the detector mounting structure each include at least one column assembly.

8. The apparatus of claim 7, wherein each of the post assemblies comprises:

the upright column is arranged along the vertical direction;

and the lifting mechanism is arranged along the upright post, is supported by the upright post, and is used for mounting the radiation source or the detector.

9. The apparatus of claim 8, wherein the lift mechanism comprises:

a lead screw arranged along the upright post;

the lifting platform is arranged on the lead screw and is in threaded connection with the lead screw, and the radiation source or the detector is fixedly arranged on the lifting platform;

when the screw rod rotates, the lifting platform can do lifting motion along the screw rod through interaction with the threads of the screw rod.

10. The device of claim 9, wherein the lifting platform is in threaded connection with the lead screw via a nut, the nut is in threaded connection with the lead screw, and the lifting platform is fixedly connected with the nut; or

The lifting platform comprises a threaded passage penetrating through the lifting platform, and the threaded passage is in threaded connection with the lead screw.

11. The apparatus of claim 9, wherein the lift mechanism further comprises at least one guide rail disposed along the column, the lift platform being slidable along the guide rail to guide the lifting motion of the lift platform.

12. The apparatus of claim 11, wherein the elevating platform is slidably connected to the guide rail by a slider, the slider is slidably connected to the guide rail, and the elevating platform is fixedly connected to the slider; or

The lift platform includes a channel therethrough for receiving the guide rail.

13. The apparatus of claim 7, wherein the radiation source mounting structure comprises a single column assembly.

14. The apparatus of claim 7 or 13, wherein the probe mounting structure comprises a plurality of mast assemblies.

15. The apparatus of claim 14, wherein the probe mounting structure further comprises a connecting beam connected between each pair of adjacent ones of a plurality of uprights in the plurality of upright assemblies.

16. The apparatus of claim 14, wherein the probe mounting structure further comprises a cross beam connected between each pair of adjacent ones of the plurality of lift platforms in the plurality of column assemblies, the probe being fixedly mounted on the cross beam and the lift platforms via the cross beam.

17. The apparatus of claim 16 wherein one end of the cross-beam is fixedly hinged to one of the adjacent lift platforms and the other end is resiliently coupled to the other of the adjacent lift platforms.

18. The apparatus of claim 14, wherein the probe mounting structure comprises two post assemblies.

19. The apparatus of claim 9, wherein the scan drive/control subsystem comprises:

the servo driving motor is used for driving a screw rod in each upright post component;

and the servo synchronous controller is used for controlling each servo driving motor to synchronously operate.

20. The apparatus of claim 1, further comprising a host computer providing a human-machine interface for controlling operation of the apparatus in response to operator commands, and for imaging and displaying based on the imaging data.

21. The apparatus of claim 1, wherein the detector is a planar form of a detector array.

22. A method for checking contraband articles in an air cargo container, which is used for checking an inspected object by using a checking device, the checking device comprises a rotary table and a scanning system, the rotary table is arranged at an object detection position, is used for bearing the inspected object and driving the inspected object to rotate, and can rotate continuously or to any preset angle position around the rotation axis of the rotary table; the scanning system is arranged around the rotary table and used for scanning an object to be detected and acquiring imaging data, and comprises a radiation source and a detector, wherein the radiation source and the detector are arranged to synchronously move along the vertical direction and can continuously move or move to any preset vertical position;

wherein the method comprises inspecting the inspected object by using the same inspection device in a plurality of operation modes, and the plurality of operation modes are selected from at least one of the following:

the device comprises a perspective plane imaging mode, a rotary table, a radiation source, a detector and a device, wherein the rotary table drives the detected object to at least one preset angle position, when the detected object is located at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device respectively forms two-dimensional perspective images of the detected object at each preset angle position according to the perspective image data at each preset angle position;

the device comprises a multi-view three-dimensional imaging mode, a rotating table, a radiation source, a detector and a device, wherein the rotating table drives the detected object to a plurality of preset angle positions, when the detected object is located at each preset angle position, the radiation source and the detector synchronously scan once along the vertical direction to obtain perspective image data at each preset angle position, and the device reconstructs a three-dimensional image of the detected object according to the perspective image data at each preset angle position;

the device comprises a CT plane imaging mode, wherein the radiation source and the detector are positioned at least one preset vertical position, when the radiation source and the detector are positioned at each preset vertical position, the rotary table drives the detected object to continuously rotate to obtain CT projection data at each preset vertical position, and the device respectively reconstructs a two-dimensional tomographic image of the detected object at each preset vertical position according to the CT projection data at each preset vertical position; and

the device comprises a radiation source, a detector, a rotary table, a CT spiral scanning projection data and a CT spiral scanning imaging mode, wherein the radiation source and the detector vertically move from a first preset vertical position to a second preset vertical position, the rotary table drives the detected object to continuously rotate, so that the detected object is spirally scanned, the CT spiral scanning projection data of the detected object between the first preset vertical position and the second preset vertical position are obtained, and the device reconstructs a three-dimensional tomographic body data image of the detected object between the first preset vertical position and the second preset vertical position according to the CT spiral scanning projection data.

23. The method of claim 22, wherein the plurality of operating modes are selected from at least two of the listed operating modes.

24. A method according to claim 22 or 23, wherein the method comprises the steps of:

the first step, using a perspective plane imaging mode to inspect the detected object, and jumping to the third step if a suspected area is found;

and a second step of inspecting the inspected object by using a multi-view three-dimensional imaging mode, and performing a third step if a suspected area is found.

And a third step of inspecting the object to be inspected by using a CT plane imaging mode or a CT spiral scanning imaging mode.