Patent Application
20170003415
The present invention relates to a technical field of radiation scanning, and specifically to a system and a method for radiation inspection on a moving object.
Nowadays, utilizing high energy radiation for automatic scanning inspection on an object moving with high speed, such as a running vehicle, can accomplish a security check for smuggled, illegal and prohibited objects, without interrupting the passing of the vehicles with high speed and is an ideal means for performing a 100% vehicle inspection. Generally, such prior inspection system at least includes a radiation source and a matching collimator for collimating rays from the radiation source into a sector-shape beam. The prior inspection system further includes several sensors for detecting the position of the object moving in a certain direction. An array of sensors are arranged opposite to the radiation source and receive the radiation rays passing through the moving object to form a digital image by which a dangerous object may be found.
However, such system can only perform inspection on a moving object running in a single specific direction and cannot perform inspection on moving objects running in other directions. For application situations where the ground traffic network is complicated or there is a limited occupation space for the system, such system cannot be used. As the result, the inspection efficiency is low and the costs of apparatus and labor are increased.
In the present invention, a system for radiation inspection on a moving object and a method for radiation inspection on a moving object are provided, and they enable radiation inspection on the moving objects running in multiple directions and enable a high working efficiency.
In the present invention, a system for radiation inspection on a moving object is provided, and it comprises: a radiation source and a radiation detector, with the radiation source emitting rays and the radiation detector collecting rays for radiation imaging, wherein the radiation source and the radiation detector are located on either side of a detection passage, respectively, and the radiation source emits the rays which are restricted within a scanning region having a first boundary plane and a second boundary plane; and the system further comprises: a plurality of detecting units arranged in sequence along a detection passage, being triggered and sending a signal when detecting that the moving object arrives or leaves; and a control module used for receiving the signal sent by the plurality of detecting units, and controlling the radiation source based on the received signal to perform radiation inspection on the moving object; wherein a first, second, and third detecting units of the plurality of detecting units are located at one side of the scanning region, and near the first boundary plane; the fourth, fifth, and sixth detecting units of the plurality of detecting units are located at the other side of the scanning region, and near the second boundary plane; wherein the first, second, and third detecting units of the plurality of detecting units have respective distances L1, L2, L3 to the first boundary plane, wherein L1>L2>L3; a fourth, fifth, and sixth detecting units of the plurality of detecting units have respective distances L4, L5, L6 to the second boundary plane, wherein L4<L5<L6; and each of L2 and L5 is not less than a length of a portion of the moving object which needs to be shielded from radiation.
Preferably, each of L3 and L4 has a value range of [0.1, 1], in meters.
Preferably, each of L2 and L5 has a value range of [1, 3], in meters.
Preferably, the control module is further used for comparing a moving speed of the moving object with a preset threshold, and terminating the radiation inspection process when the moving speed is less than the preset threshold.
Preferably, each of the second and fifth detecting units comprises at least two detecting sub-units which are arranged along the detection passage and spaced apart from one another.
Preferably, the detection passage has one or more inlets and has one or more outlets.
Preferably, in the position of the inlet of the detection passage, a traffic light and/or a movable bar are/is installed.
Preferably, in the position of the outlet of the detection passage, a traffic light and/or a movable bar are/is installed.
Preferably, in the step{circle around (2)}, after the control module receives the signal, the control module records a time point T1 at which the fourth or third detecting unit of the plurality of detecting units is triggered; the control module records a time point T2 at which the fifth or second detecting unit of the plurality of detecting units is triggered; and the control module calculates a moving speed of the moving object, wherein the speed value V=(L2−L3)/(T2−T1) or V=(L5−L4)/(T2−T1); when V is less than a preset threshold, the radiation inspection process is terminated; otherwise, after the fifth or second detecting unit of the plurality of detecting units detects that the moving object arrives, the radiation source is controlled to start emitting rays.
Preferably, when a time interval between time points at which any two adjacent detecting units of the plurality of detecting units are triggered, respectively, is larger than a preset time interval, the control module terminates the radiation inspection process.
Preferably, when the system comprises a traffic light and a movable bar, after the first or sixth detecting unit of the plurality of detecting units detects that the moving object enters the detection passage, the control module controls all the traffic lights to turn red and controls the movable bar at the inlet to be closed; after the sixth or first detecting unit of the plurality of detecting units detects that the moving object leaves the detection passage, the control module controls all the traffic lights and the movable bar to return to their ready states.
Preferably, when the system is in the ready state, all the traffic lights are green and all the movable bars are kept open.
Preferably, when the system is in the ready state, all the traffic lights are red and all the movable bars are kept closed; when the first or sixth detecting unit of the plurality of detecting units detects that the moving object arrives, the control module controls all the traffic lights to turn green and controls all the movable bars to be opened.
Preferably, when the system is in the ready state, all the traffic lights are red and all the movable bars are kept closed; when the first and sixth detecting units of the plurality of detecting units simultaneously detect that the moving object arrives, as a priority, the control modules controls the traffic light at the inlet where the first detecting unit inlet is located, to turn green and controls the movable bar to be opened.
Preferably, when the system is in the ready state, the traffic light at the inlet where the first detecting unit is located, is green and the movable bar is kept open; meanwhile, the traffic light at the inlet where the sixth detecting unit is located, is red and the movable bar is kept closed.
In another aspect, in the present invention, a system for radiation inspection on a moving object is further provided, and it comprises: a radiation source and a radiation detector, with the radiation source emitting rays and the radiation detector collecting rays for radiation imaging, wherein the radiation source and the radiation detector are located on either side of a detection passage, respectively, the radiation source emits rays which are restricted within a scanning region having a first boundary plane and a second boundary plane; and the system further comprises: a plurality of detecting units arranged in sequence along a detection passage, being triggered and sending a signal when detecting that the moving object arrives or leaves; and a control module used for receiving the signal sent by the plurality of detecting units, and controlling the radiation source based on the received signal to perform radiation inspection on the moving object; wherein the first and second detecting units of the plurality of detecting units are located at one side of the scanning region, and near the first boundary plane; the third and fourth detecting units of the plurality of detecting units are located at the other side of the scanning region, and near the second boundary plane; wherein the first and second detecting units of the plurality of detecting units have respective distances K1 and K2 to the first boundary plane, wherein K1>K2; the third and fourth detecting units of the plurality of detecting units have respective distances K3 and K4 to the second boundary plane, wherein K3<K4; and each of K2 and K3 is not less than a length of a portion of the moving object which needs to be shielded from radiation.
In another aspect, in the present invention, a method for radiation inspection on a moving object is further provided, and it comprises: step{circle around (1)}: the first or fourth detecting unit of the plurality of detecting units, when detecting that the moving object arrives, sending a signal to the control module; step{circle around (2)}: the control module, after receiving the signal and after the third or second detecting unit of the plurality of detecting units detects that the moving object arrives, controlling the radiation source to start emitting rays; step{circle around (3)}: after the third or second detecting unit of the plurality of detecting units detects that the moving object leaves, the control module controlling the radiation source to stop emitting rays.
Hereinafter, the technical solutions of the present invention will be described in detail in connection with specific embodiments and with reference to the accompanying drawings.
In the embodiment of
In the embodiment, the detecting units 110 and 160 are located at two ends of the detection passage, respectively. They may detect whether a moving object (such as a vehicle) is coming, whether the moving object has been completely in the detection passage, whether the moving object has exited the detection passage. As shown in
In the embodiment, the detecting units 120 and 150 are located in the scanning passage, on either side of the scanning region, respectively, and are each spaced apart from the scanning region by a distance that depends on the length of a portion of the moving object which needs to be shielded from radiation. For example, for a vehicle, the portion which needs to be shielded from radiation is the driving cab in which the driver is seated, and the distance of each of the detecting units 120 and 150 to a boundary of the scanning region should be not less than the length of the portion of the driving cab.
In the embodiment, it is configured such that the detecting units 120 and 150 are spaced apart from the scanning region by certain distances. That is, it is configured such that the detecting unit 120 is spaced apart from the left boundary (i.e. a vertical plane perpendicular to the paper plane in fact) of the scanning region by a certain distance and the detecting unit 150 is spaced apart from the right boundary of the scanning region by a certain distance, and specifically a distance of 1˜3 meters would be appropriate. The distance from the detecting unit 120 to the left boundary of the scanning region and the distance from the detecting unit 150 to the right boundary of the scanning region may be the same or may be different.
In some embodiment(s) of the present invention, the detecting unit 120 or 150 comprises several sensors arranged along the passage and spaced apart from one another. Each sensor may be independently considered as the detecting unit 120 or 150 for use, for the purpose of detecting and determining the portion which needs to be shielded from radiation, in various types of moving objects, and avoiding exposure of said portion under radiation. For example, for radiation inspection on various types of vehicles, it is necessary to avoid the driving cab in which the driver is seated. The arranged several sensors are spaced apart from one another by a distance, and thus can detect not only the driving cab of the type of truck vehicles having relatively large volume, but also the driving cab of the type of cars having relatively small volume, thereby enabling 100% radiation avoidance for the driving cab and the driver therein.
In some embodiment(s) of the present invention, the detecting units 130 and 140 are located on either side of the scanning region, respectively, in positions near the scanning region. For example, the detecting unit 130 is spaced apart from the left boundary of the scanning region by a distance of 0.1˜1 meter, and the detecting unit 140 is spaced apart from the right boundary of the scanning region by a distance of 0.1˜1 meter. These two distances may be the same or may be different. The detecting units 130 and 140 can detect whether the moving object has left the scanning region, and inform the control system to immediately stop ray emitting from the ray source, thereby reducing unnecessary ray irradiation.
In some embodiment(s) of the present invention, in positions near the detecting units 110 and 160, a bar and a traffic light (not shown in
During radiation scanning to the moving object, if the moving speed of the object is too low, it is inappropriate to activate radiation scanning. For this reason, during automatic inspection of the present invention, a vehicle speed detecting mechanism may be further provided. Referring to
In some embodiment(s) of the present invention, the imaging system may, according to the vehicle speed detected by the control system, perform image correction in the running direction of the vehicle to the obtained scanning image, thereby reducing image deformation that is caused due to the change in vehicle speed.
Hereinafter, the case(s) in which the vehicle enters the scanning passage from the right in
In some embodiment(s) of the present invention, in order to handle the complicated situations of the ground traffic network, the automatic inspection system may be attached to several roads in different directions in the ground traffic.
In the embodiments of
In some embodiment(s) of the present invention, the control system may set a maximum time difference between time points at which adjacent detecting units are triggered in sequence, such as 15 s. If the difference between time points of two adjacent detecting units being triggered is larger than the set value, the control system stops the inspection process and re-switches the inspection system to the ready state, so as to prevent the inspection system from being in the activated state for a long time due to accidental triggering of the detecting unit(s) or due to other faults.
In the embodiments of
In the radiation inspection, when the automatic inspection system is in the ready state, the bars at the positions of the detecting units 112 and 161 are open and the traffic lights at the positions of the detecting units 112 and 161 are green. When 112 detects that the vehicle arrives, the traffic lights at the positions of the detecting units 112 and 161 are turned red and the bar at the position of the detecting unit 161 is put down; when 112 detects that the vehicle leaves, the bar at the position of the detecting unit 112 is put down to prevent any subsequent vehicle from entering by accident; the vehicle reaches 120, 130, 140 in sequence and when the vehicle reaches the detecting unit 150, it can be determined that the vehicle head which needs avoidance has passed the scanning region and the vehicle carriage portion to be inspected has entered the scanning region; provided that the vehicle running speed is larger than the preset value, the ray source is controlled to immediately emit rays to scan the vehicle carriage for inspection; the vehicle continues to run forward, and when the vehicle leaves the scanning region, the detecting unit 140 detects that the vehicle leaves its position; the control system, after receiving the signal from 140, immediately controls the ray source to stop emitting rays, thereby reducing unnecessary ray irradiation; the vehicle leaves the detecting units 150 and 162 in sequence; when the detecting unit 162 detects that the vehicle leaves, the control system, according to the signal from 162, switches the inspection system to the ready state, turns the traffic lights at the two ends of the passage green and opens all the bars at the two ends.
In the same way, when the detecting unit 161 detects that the vehicle arrives, the traffic lights at the positions of the detecting units 112 and 161 are turned red and the bar at the position of 112 is put down; when the detecting unit 161 detects that the vehicle leaves, the bar at the position of the detecting unit 161 is put down to prevent any subsequent vehicle from entering by accident; the vehicle reaches 150, 140, 130 in sequence, when the vehicle reaches 120, it can be determined that the vehicle head which needs avoidance has passed the scanning region and the vehicle carriage to be inspected enters the scanning region; provided that the vehicle running speed is larger than the preset value, the ray source is controlled to immediately emit rays to scan the vehicle carriage for inspection; the vehicle continues to run forward, and when the vehicle leaves the scanning region, the detecting unit 130 detects that the vehicle leaves its position; the control system, after receiving the signal from the detecting unit 130, immediately controls the ray source to stop emitting rays, thereby reducing unnecessary ray irradiation; the vehicle leaves the detecting units 120 and 111 in sequence; when the detecting unit 111 detects that the vehicle leaves, the control system, according to the signal from the detecting unit 111, switches the inspection system to the ready state, turns the traffic lights at the two ends of the passage green and opens all the bars at the two ends.
In some embodiment(s) of the present invention, when the automatic inspection system is in the ready state, all the bars are put down. Only when the detecting units 110, 112, 160, 161 detect that the moving object arrives, can the bar corresponding to the running direction of the moving object be opened.
In some embodiment(s) of the present invention, in radiation inspection, when the automatic inspection system is in the ready state, the bars at the positions of the detecting units 112 and 161 are put down and the traffic lights at the positions of the detecting units 112 and 161 are red. When the detecting units detect that the moving object arrives, the control system or an operation person, according to the traffic flow condition in the two running directions, selectively opens a bar in one of the two running directions, allowing the object moving in that running direction to enter for scanning inspection. When the object moving in that running direction leaves the inspection system, the control system or an operation person, according to the traffic flow condition in the two directions, selectively opens a bar in one of the two running directions, allowing a next moving object to enter for scanning inspection.
In some embodiment(s) of the present invention, a priority inspection mechanism may be configured for the inspection system. When the inspection system is in the ready state, the bar of the passage in one running direction is configured to keep open (with the traffic light being green), while bar of the passage in another running direction is configured to keep closed (with the traffic light being red). Therefore, when there are vehicles in both directions waiting for inspection, as a priority, the vehicle on the side where the bar is open may first enters the inspection passage for scanning inspection. For example, the direction from left to right in
In the embodiment(s) of the present invention, the plurality of detecting units are reasonably arranged, and the radiation controlling process during inspection on the moving object(s) is designed accordingly. With the embodiment(s) of the present invention, the moving objects coming from different directions in the ground traffic network may be scanned for inspection, thereby enabling a high efficiency of security check, effectively avoiding the portion(s) that needs to be shielded from radiation during inspection, preventing the object running with a relatively low speed from being put under radiation scanning and thus ensuring personnel safety.
Hereinbefore, the technical solutions of the present invention are described in detail in connection with specific embodiments. The specific embodiments as described are used to facilitate understanding of the concept of the present invention. Any derivation or variation made by those skilled in the art based on the specific embodiments of the present invention will fall into the protection scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201410111164.1 | Mar 2014 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2015/073551 | 3/3/2015 | WO | 00 |
