Disclosure of Invention
An object of the application is to provide a data acquisition controlling means and security check system of detector array for solve the problem that current security check image warp, security check reliability is low.
In order to achieve the above object, the present application provides a technical solution of a data acquisition control device for a detector array, the device including:
the displacement sensor is arranged on the safety inspection machine conveying device, so that the displacement sensor sends out a pulse signal every time the safety inspection machine conveying device transmits a set distance;
the detector array comprises a plurality of detectors and integration circuits which are correspondingly connected, and is used for receiving the transmitted X-rays in the security check scanning process and sampling the received X-rays;
the controller is connected with the input end of the controller, the output end of the controller is connected with each integration circuit in a control mode, the output end of each integration circuit is connected with the controller, the controller is used for controlling the initial time and the integration time of the integration circuits according to the pulse signals of the displacement sensors to obtain sampling data of the detector, the initial time is the time point corresponding to the rising edge of the pulse signals, and the integration time is the width of the pulse signals.
The technical scheme of the data acquisition control device of the detector array has the beneficial effects that: the integration circuit in the detector array of the invention integrates according to the pulse signal of the displacement sensor, sends out a pulse signal, the integration circuit starts integrating, and the integration time is equal to the pulse width, so that the sampling data of the detector and the scanning distance of the corresponding parcel are equal and independent of the speed, and the image deformation caused by the change of the moving speed of the parcel can be avoided. Meanwhile, if the package completely stops moving, namely the transmission of the transmission device of the security inspection machine stops, the displacement sensor also stops pulse output, sampling/integration also stops, when the package restarts to move, the displacement sensor outputs pulses, the sampling/integration restarts, and each subsequent line of sampling data is arranged behind the line of data stopped, so that a complete undistorted image can be formed, and the original jigsaw problem is solved.
Furthermore, the sampling data in the interval duration of the pulse signal is the sampling data after the integration of the previous pulse signal.
Furthermore, the detector array also comprises a plurality of signal conditioning circuits, and the detector is connected with the integrating circuit through the signal conditioning circuits.
Furthermore, the integrating circuit is connected with the controller through the output of the analog-digital conversion circuit.
In addition, this application still provides a technical scheme of security check system, and the security check system includes security check machine conveyor, security check passageway, is used for sending triggering signal's trigger and being used for launching X ray after the parcel reaches the assigned position, carries out the ray source that scans to the parcel, its characterized in that, still includes detector array's data acquisition controlling means, and detector array's data acquisition controlling means includes:
the displacement sensor is arranged on the safety inspection machine conveying device, so that the displacement sensor sends out a pulse signal every time the safety inspection machine conveying device transmits a set distance;
the detector array comprises a plurality of detectors and integration circuits which are correspondingly connected, and is used for receiving the transmitted X-rays in the security check scanning process and sampling the received X-rays;
the controller is connected with the input end of the controller, the output end of the controller is connected with each integration circuit in a control mode, the output end of each integration circuit is connected with the controller, the controller is used for controlling the initial time and the integration time of the integration circuits according to the pulse signals of the displacement sensors to obtain sampling data of the detector, the initial time is the time point corresponding to the rising edge of the pulse signals, and the integration time is the width of the pulse signals.
The technical scheme of the security inspection system has the beneficial effects that: the integration circuit of the detector array in the security inspection system provided by the invention integrates according to the pulse signal of the displacement sensor, sends out a pulse signal, the integration circuit starts integrating, and the integration time is equal to the pulse width, so that the sampling data of the detector is equal to the scanning distance of the corresponding parcel and is independent of the speed, and the image deformation caused by the change of the moving speed of the parcel can be avoided. Meanwhile, if the package completely stops moving, namely the transmission of the transmission device of the security inspection machine stops, the displacement sensor also stops pulse output, sampling/integration also stops, when the package restarts to move, the displacement sensor outputs pulses, the sampling/integration restarts, and each subsequent line of sampling data is arranged behind the line of data stopped, so that a complete undistorted image can be formed, and the original jigsaw problem is solved.
Furthermore, the sampling data in the interval duration of the pulse signal is the sampling data after the integration of the previous pulse signal.
Furthermore, the detector array also comprises a plurality of signal conditioning circuits, and the detector is connected with the integrating circuit through the signal conditioning circuits.
Furthermore, the integrating circuit is connected with the controller through the output of the analog-digital conversion circuit.
Further, the trigger is a light barrier.
Further, the light barrier is arranged in the security inspection channel and close to the entrance of the security inspection channel.
Detailed Description
Embodiment of the security inspection system:
the invention has the main conception that based on the problem of image deformation caused by different wrapping speeds, the detector array carries out integral sampling according to pulse signals of the displacement sensor, and the displacement sensor acquires the transmission distance of the conveying device of the security inspection machine, so that the speed is irrelevant, and the phenomenon that the image is not deformed is ensured.
The security inspection system provided by the embodiment is shown in fig. 1 and 2, and comprises an upper computer 1, adetector array 2, a data acquisition andtransmission unit 3, adisplacement sensor 4, aG1 light barrier 5, acontrol unit 6, aradiation source 7 and a security inspectionmachine conveying device 8. Thedetector array 2, the data acquisition andtransmission unit 3 and thedisplacement sensor 4 form a data acquisition control device of thedetector array 2, so that the data acquisition control of thedetector array 2 is realized, wherein the data acquisition andtransmission unit 3 is used as a controller, and the sampling time sequence of thedetector array 2 is also controlled on the basis of data transmission.
The security inspectionmachine conveying device 8 comprises a motor and a conveying belt, the motor drags the conveying belt to move, packages are placed on the conveying belt, and the conveying belt can move to drive the packages to move.
The safety inspectionmachine conveying device 8 is provided with adisplacement sensor 4, and thedisplacement sensor 4 sends out a pulse signal when the conveying belt moves for a certain distance (the scanned package moves with the conveying belt at the same time, so that the scanned package moves for a certain distance at the same time, namely, the scanned package moves for a certain distance at the same time).
A security check channel is arranged above a security checkmachine conveying device 8, aradiation source 7 is arranged below the security checkmachine conveying device 8 and corresponds to the position of the security check channel, adetector array 2 is arranged at the top of the security check channel, theradiation source 7 is used for emitting X rays, thedetector array 2 is a linear array detector and is composed of a plurality of receiving devices (each receiving device comprises a detector and a related circuit), and the receiving devices are arranged in a straight line in the X ray emitting direction. Theradiation source 7 generally adopts a collimator to shape a conical beam emitted by a ray tube into a fan-shaped beam so as to be matched with the linear array detector; the linear array detector receives X-rays transmitted through the envelope from theradiation source 7.
Thedetector array 2, as shown in fig. 3, includes a plurality of detectors, and a signal conditioning circuit, an integrating circuit, and an analog/digital converting circuit connected in sequence to each detector.
The G1light barrier 5 is arranged inside the security channel and is generally fixed near the entrance of the security channel, and the G1light barrier 5 comprises an infrared emitter and an infrared receiver oppositely arranged on both sides of the security channel. When the scanned parcel moves to the middle of infrared emitter and infrared receiver, the infrared ray that infrared emitter sent is sheltered from, and the signal that infrared receiver received changes, and the output is with the opposite signal when not sheltering from, consequently can judge whether the parcel is close to and leave according to the change of this signal, and then confirm the moment thatray source 7 opened and closed.
The connection relationship between each part and thecontrol unit 6, the data acquisition and transmission unit 3 (i.e. the data processor in fig. 3) and the upper computer 1 is shown in fig. 3, thedisplacement sensor 4 is connected with the input end of the data acquisition andtransmission unit 3, the output end of the data acquisition andtransmission unit 3 is connected with each integration circuit in a control way, and the output of each analog/digital conversion circuit in thedetector array 2 is connected with the data acquisition andtransmission unit 3; the upper computer 1 is in communication connection with the data acquisition andtransmission unit 3. The data acquisition andtransmission unit 3 is used for controlling the start time and the integration time of integration of each integration circuit according to the pulse signal of thedisplacement sensor 4, collecting the acquired data of thedetector array 2, transmitting the data to the upper computer 1, and the upper computer 1 receives the data sent by the data acquisition andtransmission unit 3 and displays the data on a screen according to a certain format.
The input end of thecontrol unit 6 is connected with theG1 light barrier 5, and the output end is connected with theradiation source 7 and the motor of the security inspectionmachine conveying device 8. Thecontrol unit 6 is used for controlling the starting and stopping of the security inspectionmachine conveying device 8 and controlling the opening and closing of theradiation source 7 according to the signal change of theG1 light barrier 5.
In order to avoid the problem of image deformation caused by different transmission speeds, the whole process of the security inspection system is as follows:
1) and starting the machine, wherein thecontrol unit 6 controls the motor to be powered on, and the conveying belt of the safety inspectionmachine conveying device 8 moves, so that the safety inspectionmachine conveying device 8 works.
2) Thedisplacement sensor 4 pulses with the movement of the conveyor belt, and each time the conveyor belt moves a certain distance, thedisplacement sensor 4 sends out a corresponding pulse, for example: thedisplacement sensor 4 sends out 1 pulse every time the conveyor belt moves 1 mm.
3) The data acquisition andtransmission unit 3 controls an integrating circuit to perform integral starting time and integral time and A/D conversion time according to the pulse of thedisplacement sensor 4 so as to obtain sampling data of each detector, and the sampling data of each detector on the linear array are combined in a serial mode, a parallel mode or a serial-parallel combined mode and are sent to the upper computer 1;
4) the host computer 1 performs format conversion on the received data to obtain a scanned image of the scanned parcel.
Specifically, the data acquisition andtransmission unit 3 controls the integrating circuit and the upper computer 1 to perform the following processing procedures:
when the conveying belt moves for 1mm, thedisplacement sensor 4 detects the movement and sends 1 pulse, the data acquisition andtransmission unit 3 controls the integration circuit to start integration, thedetector array 2 outputs the acquired data (namely, the data after integration) once, and the data acquisition andtransmission unit 3 obtains a line of data which is a row of pixel gray values corresponding to the image of the upper computer;
when theray source 7 is not opened, the data output by thedetector array 2 is data without X-ray irradiation, which is also called background data, and no image appears on the screen of the upper computer;
when a scanned package is placed on the safety inspectionmachine conveying device 8 and conveyed into a safety inspection channel, and the G1light barrier 5 is triggered, thecontrol unit 6 controls theradiation source 7 to be opened, because theradiation source 7 is not shielded by the package, the X-rays emitted by theradiation source 7 irradiate thedetector array 2 without shielding, the data output by thedetector array 2 is the strongest ray intensity, and the data is a full scale value;
when the scanned parcel blocks X-rays, namely the X-rays pass through the scanned parcel, the energy and the dose value of the rays collected by thedetector array 2 are changed, the change quantity of the ray energy and the dose value has close relation with the thickness, the density and the type of the substances passing through the substances, and then relevant data included in the scanned item are output;
when the scanned parcel continues to move away from the scanning range of the X-ray, thecontrol unit 6 controls theray source 7 to be closed, and the scanning is finished.
In the above process, each time thedisplacement sensor 4 outputs a pulse, the data acquisition andtransmission unit 3 acquires line data, the data acquisition andtransmission unit 3 sorts the acquired line data, and transmits the line data or lines of data to the upper computer 1 according to a protocol, the upper computer 1 displays the data according to a certain format, and specifically, the sampling process of the control integration circuit of the data acquisition andtransmission unit 3 is as shown in fig. 4:
every time the parcel moves a certain distance (as a in fig. 4, moves 1l, 2l, 3l, 4l, the corresponding time is T1、T2、T3、T4) I.e. the belt moves a certain distance, thedisplacement sensor 4 detects the movement and generates a pulse signal, as shown in b of fig. 4, the rising edge of the pulse signal corresponds to the position of the package, and therefore the corresponding time point is T1、T2、T3、T4The distance intervals of movement are equal, but the time intervals are not necessarily equal, depending on the transmission speed;
the X-ray traverses a transverse slice (direction of movement, perpendicular to the fan beam plane) of the object, and the signal value generated at each detector is a continuous signal, as shown at c in fig. 4;
under the action of the pulse signal, the integrating circuit is controlled to start integrating, and the starting time of the integrating is the time point corresponding to the rising edge of the pulse signal, namely T1、T2、T3、T4The integration time Δ t is the width of the pulse signal, the integration time Δ t is unchanged (the minimum interval between rising edges is smaller than that in normal operation, as shown in D of fig. 4, the signal value after integration is maintained until the next integration is started, that is, the sampling data in the interval duration of the pulse signal is the sampling data after the integration of the previous pulse signal, and finally, the analog-to-digital conversion circuit (that is, the a/D conversion circuit) converts the signal output by the integration circuit into a digital signal and outputs the digital signal to the data acquisition andtransmission unit 3, and further, the digital signal is uploaded to the upper computer 1.
The host computer 1 firstly places the received data in a memory, calculates a characteristic value represented by each data in the data according to the characteristic that the X-ray passes through the substance, and maps each line data into line data, the line data are arranged to form two-dimensional data, and a complete scanning image is displayed on a screen through gray scale and color conversion, wherein each line data corresponds to each point of the object.
Of course, when the computer displays the images, the images of one package can be all displayed at one time; it is also possible to display several columns of data at a time, in a step-by-step manner, sometimes referred to as a "scroll".
In the above embodiment, the G1light barrier 5 may be used as a photoelectric trigger to control theradiation source 7 to be turned on and off, and as another embodiment, a mechanical trigger may also be used to issue a trigger signal, which is not limited by the present invention.
In the above embodiments, thedetector array 2 includes the signal conditioning circuit, the integrating circuit, and the analog/digital converting circuit, so that the data output by thedetector array 2 has been processed, as another embodiment, the signal conditioning circuit, the integrating circuit, and the analog/digital converting circuit may also be used as separate devices to process the data collected by the detector.
The starting point of each sampling/integration of thedetector array 2 is determined by the pulse signal sent by thedisplacement sensor 4, so that the distance of the package scanned corresponding to each output row of data is equal and is irrelevant to the scanning speed. Therefore, the variation in the moving speed of the object does not cause the distortion of the image. Meanwhile, if the conveying belt (i.e. the scanned package) completely stops moving, thedisplacement sensor 4 also stops pulse output, sampling/integration also stops, when the conveying belt restarts moving, thedisplacement sensor 4 outputs pulses, sampling/integration restarts, and each subsequent row of data is arranged behind the row of data stopped, so that a complete undistorted image can be formed, and the original jigsaw problem is well solved.
The data acquisition control device embodiment of the detector array:
the specific structure and working process of the data acquisition control device of the detector array are already described in the above security inspection system, and are not described herein again.