CN102095421B - Direction deviation correction equipment and method and mobile radiation inspection system - Google Patents

Abstract

A direction correction device and method for a mobile radiation inspection system, the mobile radiation inspection system includes a mobile device, and the direction correction device includes: a direction detection device that detects the moving direction of the mobile device and generates a detection signal indicating the moving direction; controls the mobile device A direction control device for the direction of movement; and a control unit that calculates a deviation value between the movement direction and a predetermined direction according to a detection signal received from the direction detection device, and drives the direction control device according to the deviation value to correct the movement direction to a predetermined direction superior. The direction detection device includes at least one photoelectric switch, and the control unit controls the distance between the mobile device and the inspected object to a predetermined distance according to the signal received from the at least one photoelectric switch. According to the direction deviation correcting device of the present invention, it can automatically control the mobile radiation inspection system to run linearly along the predetermined direction during operation, which improves the degree of automatic control, and has simple structure, convenient installation and disassembly, and low cost.

Description

Direction correction device and method and mobile radiation inspection system

This application is a divisional application of the patent application with the application number 200710064027.7, the title of the invention is "direction correction equipment and method and mobile radiation inspection system", and the application date is February 16, 2007.

technical field

The invention relates to a mobile radiation inspection system and its direction deviation correction equipment and direction deviation correction method. In particular, the present invention relates to a vehicle-mounted mobile radiation inspection system that utilizes rays to image inspected objects such as containers/loading vehicles so as to conduct radiation inspections on them; and a direction correction device for the vehicle-mounted mobile radiation inspection system, wherein When the moving direction of the moving device of the mobile radiation inspection system deviates from a predetermined direction, the direction correction device automatically corrects the moving direction to the predetermined direction; and is used for correcting the vehicle-mounted mobile radiation inspection The direction correction method of the moving direction of the system.

Background technique

The vehicle-mounted mobile radiation inspection system for inspection of inspected objects such as containers/cargo vehicles is a necessary inspection equipment for customs, civil aviation airports and railway stations. The vehicle-mounted mobile radiation inspection system uses the principle of radiation imaging to obtain a perspective image of the goods in the container/cargo vehicle by scanning the container/cargo vehicle without opening the container or carload vehicle. By analyzing the images, suspicious or prohibited items hidden in the cargo can be found.

The mobile container/carrying vehicle inspection system is usually integrated on a chassis vehicle, thus, the mobile radiation inspection system is usually also called a scanning vehicle or a vehicle-mounted mobile radiation inspection system, and the chassis vehicle is used as an inspection system mobile device. During the inspection work, the inspected container/cargo vehicle is parked in the designated area to be inspected and scanned by the scanning vehicle. During the scanning process, the scanning vehicle reciprocates in a straight line along a predetermined direction parallel to the inspected container/cargo vehicle.

However, due to the uneven weight distribution of the scanning vehicle, uneven ground, inconsistent wheel air pressure, etc., the moving direction of the scanning vehicle may deviate from the predetermined direction parallel to the inspected container/cargo vehicle after several scans, if it is not corrected in time If the direction of the scanning vehicle deviates, it may cause an accident of colliding with the inspected container/cargo vehicle.

In order to correct the deviation of the moving direction of the scanning vehicle, the traditional mobile container/cargo vehicle inspection system needs to stop scanning after several times of reciprocating scanning, and the operator will correct the moving direction of the scanning vehicle to the predetermined direction, which greatly affects system efficiency.

In addition, in order to correct the deviation of the moving direction of the scanning car, there is a special driver in the cab of the scanning car, and the driver corrects the moving direction of the scanning car during the scanning process, however, this increases the labor cost. At the same time, due to the scattering of rays during scanning, it will harm the health of the driver.

Contents of the invention

The present invention aims to at least partly solve the problems existing in the prior art. According to the automatic direction correction equipment and method of the vehicle-mounted mobile radiation inspection system according to the embodiment of the present invention, the mobile radiation inspection system can be automatically controlled without manual participation When working, it keeps running in a straight line in a predetermined direction and improves the degree of automatic control of the system. The invention has simple structure, convenient installation and disassembly, low cost, and does not affect the driving of the mobile radiation inspection system on the road.

Correspondingly, according to the first aspect of the present invention, a direction correction device for a mobile radiation inspection system is proposed, the mobile radiation inspection system includes a moving device, and the direction correction device includes: a direction detection device, the Direction detection means detects the moving direction of the mobile device and generates a detection signal indicating the moving direction; a direction control means for controlling the moving direction of the mobile device; and a control unit, the control unit A deviation value between the moving direction and a predetermined direction is calculated based on the detection signal received from the direction detecting means, and the direction control means is driven based on the deviation value so as to correct the moving direction to the predetermined direction.

Preferably, the direction detection device includes first and second distance detectors, and the first and second distance detectors generate first and second distance detection signals respectively, wherein the control unit according to the first and second The distance detection signal calculates the deviation value.

Further, the first and second distance detectors detect first and second distances from the mobile device to the inspected object.

Preferably, the direction correction device further includes a reference member, wherein the first and second distance detectors detect a first distance and a second distance from the moving device to the reference member.

Preferably, said first and second distance detectors comprise laser ranging sensors.

Preferably, the control unit includes: an analog/digital converter that converts the first and second distance detection signals from analog signals to digital signals; a processor that converts the calculating the deviation value for the first and second distance detection signals of the digital signal so as to generate a driving signal corresponding to the deviation value; a signal driver receiving and increasing the driving signal; and a driving circuit, the The driving circuit drives the direction control device according to the increased driving signal received from the signal driver so as to correct the moving direction of the moving device.

Furthermore, the control unit further includes a signal isolator connected between the output of the analog/digital converter and the input of the processor for isolating an input signal input to it and an output signal output therefrom .

Furthermore, the signal isolator includes a photoelectric isolator.

Preferably, the processor includes a single-chip microcomputer.

Preferably, the direction control device includes: a steering wheel for controlling the moving direction of the mobile device; and an actuator detachably engaged with the steering wheel and driven by a control unit so as to drive the steering wheel to rotate to control the movement The direction of movement of the device.

Furthermore, the direction control device further includes a link mechanism, one end of which is connected to the actuator and the other end is detachably engaged with the steering wheel of the mobile device.

Specifically, the connection mechanism includes: a connecting rod, one end of the connecting rod is connected with the actuator; a strut, the other end of the connecting rod is connected with the strut through a joint bearing, and a a nut for positioning the connecting rod; a mounting plate to which the strut is mounted on a top surface and whose sides are detachably joined to the outer periphery of the steering wheel to drive the steering wheel to rotate.

Furthermore, the direction control device further includes a bracket and a cross block, wherein the cross block is hinged with the bracket to form a universal joint, and the actuator is mounted on the bracket through the cross block.

Specifically, the direction control device further includes: a support plate, on which the bracket is mounted; a protection switch, on which the protection switch is mounted; and a pressure plate, which is connected to the on the universal joint so that when the actuator and linkage together are disengaged from the steering wheel, the pressure plate hits the guard switch to de-energize the actuator.

Preferably, wherein the actuator comprises: a motor driven by the control unit; a worm gear connected to an output shaft of the motor; and a worm meshed with the worm gear, and The axial end of the worm is connected with the connecting mechanism.

Preferably, the actuator includes a hydraulic cylinder driven by the control unit and whose cylinder rod is connected to the connecting mechanism.

Furthermore, the actuator comprises an air cylinder driven by the control unit and whose cylinder rod is connected to the connecting mechanism.

Optionally, the direction control device includes: a transmission device, the transmission device is driven by the control unit; and a flexible traction member, the two ends of the flexible traction member are respectively connected to the transmission device around the steering wheel.

Furthermore, the flexible traction member is a traction rope.

Preferably, the traction rope is detachably engaged in the groove on the outer circumference of the steering wheel through a clip and a screw.

Preferably, the transmission device includes: a motor driven by a control unit; and a double output shaft reducer driven by the motor, both ends of the traction rope are respectively connected to two output shafts of the double output shaft reducer.

Preferably, the transmission device further includes: first and second couplings, the input sides of the first and second couplings are respectively connected to the two output shafts of the reducer; the first and second winding shafts , the first and second reel shafts are respectively connected to the output sides of the first and second couplings and are respectively supported by the first and second support bases; and the first and second reels, the first and The second reel is respectively mounted on the first and second reel shafts, wherein the two ends of the pulling rope are respectively wound on the first and second reel.

Furthermore, the transmission device further includes first and second adjusting devices, and the first and second adjusting devices are used to adjust the tension of the pulling rope.

Furthermore, the transmission device further includes first and second overrunning clutches disposed in the first and second couplings, respectively.

Preferably, the overrunning clutch includes an internal ratchet overrunning clutch.

In addition, the reference member includes an integral flat member disposed parallel to the predetermined direction.

Optionally, the reference component includes a plurality of flat plate segments, and the plurality of flat plate segments are spaced apart from each other in the predetermined direction and arranged in alignment.

Preferably, the direction detection device includes at least one photoelectric switch, wherein the control unit controls the distance between the mobile device and the inspected object to be a predetermined distance according to a signal received from the at least one photoelectric switch.

Preferably, there are two photoelectric switches.

Preferably, the control unit includes: a signal collector transmitter, used to collect the signals of the first and second distance detectors and the photoelectric switch; and a signal receiver, used for wirelessly receiving signals from the data collected The signal sent by the transmitter transmitter.

According to a second aspect of the present invention, a mobile radiation inspection system is proposed, including the direction correction device according to the first aspect of the present invention.

According to a third aspect of the present invention, a direction correction method for correcting the moving direction of a mobile radiation inspection system is proposed, wherein the mobile radiation inspection system has a mobile device, and the direction correction method includes: detecting the movement direction of the mobile device moving direction and generating a detection signal indicating the moving direction; calculating a deviation value between the moving direction and a predetermined direction based on the detection signal and automatically correcting the moving direction to the predetermined direction according to the deviation value.

According to the automatic direction deviation correction device and method of the present invention and the mobile radiation inspection system using them, when the moving direction of the mobile system deviates from the predetermined direction, the control unit calculates the deviation value between the moving direction and the predetermined direction according to the detected detection signal, And the direction control device is driven based on the calculated deviation value, thereby correcting the moving direction of the mobile device to a predetermined direction, so that the mobile device moves linearly in the predetermined direction.

Therefore, when the direction deviation is corrected, the operation of the inspection system does not need to be stopped, and the control unit automatically completes the direction correction, which improves work efficiency and safety performance, and has a simple structure, convenient installation and disassembly, and low cost.

In addition, according to the preferred embodiment of the present invention, by setting two photoelectric switches, the distance between the mobile device and the object to be inspected, such as a container vehicle, can be controlled to a predetermined distance, thereby preventing the mobile device from colliding with the object to be inspected. Checked target.

Description of drawings

FIG. 1 is a schematic diagram of a direction correction device for a mobile radiation inspection system according to a first embodiment of the present invention;

Fig. 2 is the top view showing the working state of the direction correction device according to the present invention, wherein the first embodiment of the reference part is shown;

Fig. 3 is a top view showing the working state of the direction correction device according to the present invention, wherein a second embodiment of the reference part is shown;

4 is a schematic diagram of a direction correction device according to a second embodiment of the present invention;

Fig. 5 is a structural schematic diagram of the direction control device according to the first embodiment of the present invention, which shows that the direction control device is in the working state;

Fig. 6 is a schematic top view of the direction control device shown in Fig. 5;

FIG. 7 is an enlarged schematic view of the part shown by mark C in FIG. 5;

Fig. 8 is a structural schematic diagram of the direction control device shown in Fig. 5 in a non-working state, wherein the actuator of the direction control device is separated from the steering wheel;

9 is a schematic structural diagram of a direction control device according to a second embodiment of the present invention;

Fig. 10 is a schematic top view of the direction control device shown in Fig. 9 after being rotated clockwise by 90 degrees;

Fig. 11 is a structural schematic diagram of the transmission device of the direction control device shown in Fig. 9;

Fig. 12 is a schematic top view of the transmission device shown in Fig. 11;

13 is a schematic diagram of the principle of a signal isolator according to an embodiment of the present invention;

14 is a schematic circuit diagram of a signal driver according to an embodiment of the present invention;

Fig. 15 is a flowchart of a method for correcting a direction according to an embodiment of the present invention.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures, which are exemplary and should not be construed as limitations of the present invention.

FIG. 1 is a schematic diagram of a direction correction device 100 for a mobile radiation inspection system 7 according to the present invention, and FIG. 2 shows a top view of the direction correction device 100 in a working state.

In an embodiment of the present invention, the mobile radiation inspection system 7 includes a moving device 5 that drives the entire inspection system 7 to move. In other words, the components of the inspection system 7, such as radiation sources, detectors, imaging control systems, etc., are all arranged on the mobile device 5, which can be a chassis vehicle (such as a motor vehicle with a chassis frame), for example. Therefore, the mobile inspection system 7 is generally called a scanning vehicle or a vehicle-mounted mobile radiation inspection system.

However, it should be noted that the mobile device 5 of the mobile radiation inspection system 7 is not limited to a chassis vehicle, and may be any suitable mobile device in the field, such as a trailer pulled by a motor vehicle or other traction devices.

As shown in Figures 1-2, a deflection correction device 100 for a mobile radiation inspection system according to an embodiment of the present invention includes a reference component 1, a first distance detector 2a and a second distance detector 2b as a direction detection device, and the direction A control device 4, and a control unit 3.

The first and second distance detectors 2a and 2b are arranged on the mobile device 5 of the scanning vehicle, and are spaced apart by a predetermined distance L in the moving direction A of the scanning vehicle, for detecting the first distance between the reference part 1 and the mobile device 5 A distance L1 and a second distance L1 for generating first and second distance detection signals. The first and second distance detectors 2a and 2b include, but are not limited to, laser ranging sensors that emit laser light to the reference part 1 to measure the first and second distances between the mobile device 5 and the reference part 1. Distance L1 and L2.

In the embodiment shown in Figures 1 and 2, the first and second distance sensors 2a and 2b are preferred embodiments of the direction detection means. However, the direction detection means is not limited to the above-mentioned first and second distance sensors 2a and 2b, and may include a detection signal capable of detecting the moving direction of the mobile device 5 and generating a detection signal indicating the moving direction of the mobile device 5 and the detection signal. Any suitable means of signal transmission to the control unit 3, for example, may only be provided with a distance detector, which also enables correction of the direction deviation of the mobile device.

The direction control device 4 is used to control the moving direction of the mobile device 5 . The control unit 3 receives the first and second distance detection signals from the first and second distance detectors 2a and 2b, and calculates the deviation between the moving direction A and the predetermined direction B according to the first and second distance detection signals value, and then drive the direction control device 4 according to the calculated deviation value so as to correct the moving direction A to a predetermined direction B, which is, for example, parallel to the longitudinal central axis of the inspected vehicle 6 as the inspected object. direction.

In the embodiment shown in FIG. 2 , the reference component 1 is in the form of a flat plate, and is arranged in parallel on the left side of the vehicle 6 to be inspected. During the inspection of the inspected vehicle 6, the scanning vehicle 7 passes between the reference part 1 and the inspected vehicle 6, thereby measuring the first and second distances L1 in real time from the laser light emitted from the first and second distance detectors 2a and 2b and L2, and transmit the resulting first and second distance detection signals to the control unit 3.

In the embodiment shown in FIG. 1 and FIG. 2, the first and second distance detectors 2a and 2b transmit the first and second distance detection signals to the control unit 3 through cables. Optionally, the first and second distance detection signals may also be sent to the control unit 3 by wireless transmission (details will be described below).

Optionally, the reference part 1 in the form of a flat plate can also be arranged on the right side of the inspected vehicle 6, and during the inspection of the inspected vehicle 6, the scanning car 7 moves on the left side of the inspected vehicle 6, at this time, the reference part The height of 1 should be able to ensure that the laser light emitted from the first and second distance detectors 2a and 2b can reach the reference component 1 without being blocked by the inspected vehicle 6 . Of course, the reference component 1 can also be directly arranged on the vehicle 6 to be inspected.

Optionally, the reference component 1 is not an essential part of the deviation correction equipment, for example, the purpose of detecting the moving direction of the mobile device 5 can be realized by detecting the distance between the mobile device 5 and the vehicle 6 to be inspected, that is to say, the object to be inspected The vehicle 6 can replace the separately provided reference component 1 . It can be understood that the reference component 1 can also be arranged on the vehicle 6 to be inspected.

It should be noted that the length of the reference component 1 should generally be greater than the moving area of the scanning vehicle 7, so as to ensure that the laser beams emitted from the first and second distance detectors 2a and 2b are blocked by the reference component 1 during the entire scanning inspection period.

As shown in Figure 3, another embodiment of the reference part 1 is shown. In the embodiment shown in Figure 3, the reference part 1 is in the form of a plurality of flat plate segments, for example, four Plate segments 1a-1d, but the present invention is not limited thereto, any suitable number of plate segments may be used. Said four plate segments 1a-1d are spaced apart in an arrangement parallel to said predetermined direction B and aligned with each other.

As shown in Figure 1, preferably, control unit 3 comprises the A/D converter (analog/digital converter) 8 that is connected with first and second distance detector 2a and 2b by cable, processor 9, signal driver 11 , and drive circuit 12. More preferably, the control unit 3 further includes a signal isolator 9 .

The A/D converter 8 is used to convert the first and second distance detection signals from the first and second distance detectors 2a and 2b from analog signals into digital signals, and convert the first and second distance detection signals in the form of digital signals into digital signals. The distance detection signal is transmitted to the signal isolator 9 .

As shown in Fig. 13, one embodiment of the signal isolator 9 is shown. In the embodiment shown in FIG. 13 , the signal isolator 9 is a photoelectric isolator, and the photoelectric isolator 9 transmits electrical signals through an optical medium. The photoelectric isolator 9 has a good isolation effect on the input signal input to it and the output electrical signal output therefrom. The photoelectric isolator 9 is generally composed of three parts: light emission, light reception and signal amplification, and the first power supply VCC1 and the second power supply VCC2 are respectively provided on the input and output sides of the light, and the first power supply VCC1 and the second power supply VCC2 is connected to the photoelectric isolator 9 through the first and second resistors R1 and R2 respectively. The input signal drives the light-emitting diode (LED) to emit light of a certain wavelength. The light is received by the photodetector to generate a photocurrent, which is further amplified and output, thereby completing the conversion of "electricity-optical-electricity". This plays the role of isolation between input and output. Since the input and output of the photoelectric isolator 9 are isolated from each other, its electrical signal transmission has the characteristics of unidirectionality, so it has good electrical insulation ability and anti-interference ability.

In the present invention, the signal isolator 9 can be any suitable signal isolator available in the market, not limited to the above photoelectric isolator.

The photoelectric isolator 9 receives the digital distance detection signal from the A/D converter 8, and transmits the signal to the processor 10 after undergoing electrical-optical-electrical conversion.

According to the present invention, the processor 10 can be a single-chip microcomputer, a chip, a programmable logic controller (PLC), a computer, or any other suitable processing device. The processor 10 receives the first and second distance detection signals from the photoelectric isolator 9, and calculates the distance between the moving direction A of the mobile device 5 (that is, the scanning vehicle 7) and the predetermined direction B according to the first and second distance detection signals. an offset value, thereby generating a drive signal corresponding to the offset value.

For example, if the deviation value is zero, the processor 10 determines that the moving direction A is consistent (parallel) with the predetermined direction B, and if the deviation value is not zero, the processor 10 determines that there is a deviation between the moving direction A and the predetermined direction B (i.e. , there is a certain angle between the moving direction A and the predetermined direction B).

For example, if the deviation value is positive, the processor 10 determines that the moving direction A deviates to the left relative to the predetermined direction B in FIGS. The predetermined direction B deviates to the right in FIGS. 2 and 3 .

It should be noted that the above determination method by the processor 10 is only an example, and the present invention is not limited thereto. For example, when the first and second distance detectors 2a and 2b are arranged on the mobile device 5, due to installation errors, even if the longitudinal central axis of the mobile device 5 is parallel to the reference member 1, the first and second distance detectors 2a and There may also be a difference in the initial distance between 2b and the reference part 1 . However, the difference can be used as a reference zero value by zeroing. For those of ordinary skill in the art, the processor 10 can use any suitable method in the art to calculate the deviation value based on the first and second distance detection signals, thereby judging whether the moving direction A deviates from the predetermined direction B, And generate a driving signal corresponding to the deviation value, and then use the driving signal to drive the direction control device. For example, the processor 10 may use the ratio of the first and second distances L1 and L2 to determine whether the moving direction A deviates from the predetermined direction B.

The signal driver 11 is used to receive a driving signal from the processor 10 and output the driving signal with an increased driving current.

As shown in FIG. 14 , a schematic circuit diagram of the signal driver is shown. When the processor 10 is a single-chip microcomputer, the driving current output by the single-chip microcomputer 10 as a driving signal is generally relatively small, such as less than 50mA. In order to drive a larger load, a signal driver 11 is usually used to increase the driving current output from the single-chip microcomputer 10. For example, as shown in FIG. 14 , after the input signal passes through the signal driver 11 composed of a Darlington tube array, the driving current can be increased to 500mA.

The signal driver 11 transmits the increased driving current to the driving circuit 12 , thereby driving the direction control device 4 .

A direction deviation correcting device according to a second embodiment of the present invention will be described below with reference to FIG. 4 . As shown in Figure 4, the direction correction device for the mobile radiation inspection system according to the second embodiment of the present invention includes a first distance detector 2a' and a second distance detector 2b', a first photoelectric switch 45 and a second distance detector The photoelectric switch 46, the direction control device 4 (see FIG. 1), the control unit 3 (see FIG. 1), and a reference component (not shown) arranged in front or rear of the mobile device 5. The first distance detector 2a', the second distance detector 2b' and the first photoelectric switch 45 and the second photoelectric switch 46 constitute a direction detection device. The control unit 3 includes a signal collector transmitter 43 and a signal receiver 44 , and other components of the control unit 3 are the same as those in the first embodiment, and will not be repeated here.

The signal collector transmitter 43 is used to collect the signals of the first distance detector 2a' and the second distance detector 2b' and the first photoelectric switch 45 and the second photoelectric switch 46, and wirelessly transmit the signals to the signal receiver 44. Then, the signal receiver 4 sends the received signal to the processor 10, for example, through the A/D converter 8, so as to judge whether the moving direction A of the mobile device 5 deviates from the predetermined direction and calculate the deviation value (it should be understood that , even if there is no deviation, the processor 10 can also calculate the deviation value, but the deviation at this time is zero).

The first photoelectric switch 45 and the second photoelectric switch 46 are used to send, for example, on and/or off signals to the control unit 3, so that the control unit 3 receives signals from the first photoelectric switch 45 and the second photoelectric switch 46. The distance between the mobile device 5 and the inspected vehicle 6 is controlled at a predetermined distance, thereby preventing the mobile device 5 from moving leftward or rightward relative to the inspected vehicle 6 in FIG. 4 . In other words, the control unit 3 judges whether the mobile device 5 has translated relative to the inspected vehicle 6 according to the signals received from the first photoelectric switch 45 and the second photoelectric switch 46, so as to avoid performing the gate-shaped inspection system for scanning and imaging the inspected vehicle. The frame 48 collides with the vehicle under inspection.

As shown in Figure 4, a shield 47 can be provided on the moving device 5. When the moving device 5 does not move relative to the inspected vehicle 6, that is, the distance between the moving device 5 and the inspected vehicle 6 is a predetermined distance, the first photoelectric The switch 45 is turned on and the second photoelectric switch 46 is blocked by the blocking member 47 (that is, the second photoelectric switch 46 is turned off).

The operation of the direction correcting device according to the second embodiment of the present invention will be briefly described below.

For example, when the mobile device 5 is about to start moving so that the inspected vehicle 6 is checked, if the distance between the mobile device 5 and the inspected vehicle 6 is greater than a predetermined distance, then the first and second photoelectric switches 45 and 46 are all disconnect. The control unit 3 receives a signal indicating that both the first and second photoelectric switches 45 and 46 are turned off, thereby determining that the mobile device 5 translates to the left in FIG. 4 relative to the inspected vehicle 6 . Next, the control unit 3 generates a corresponding drive signal to drive the direction control device 4, thereby adjusting the moving direction of the mobile device 5 and further adjusting the distance between the mobile device 5 and the vehicle 6 to be inspected. When the control unit 3 receives the instruction again When the first photoelectric switch 45 is turned on and the second photoelectric switch 46 is turned off, the drive direction control device 4 is reset (that is, the moving device 5 is moved linearly in a direction parallel to the predetermined direction).

When the control unit 3 receives the signal indicating that the first and second photoelectric switches 45 and 46 are all conducting, then it is determined that the distance between the mobile device 5 and the checked vehicle 6 is less than a predetermined distance, at this time, the control unit 3 passes the direction The operation of the control device 4 to adjust the moving direction of the mobile device 5 is opposite to the above situation, and will not be repeated here.

Thus, according to the second embodiment of the present invention, by setting the first distance detector 2a' and the second distance detector 2b' and the first photoelectric switch 45 and the second photoelectric switch 46, not only the mobile device 5 can be monitored in real time direction of movement, and can control the distance from the mobile device 5 to the inspected vehicle 6.

It should be noted that, in the direction correction device according to the second embodiment of the present invention, the first distance detector 2a' and the second distance detector 2b' may not be provided, but only the first photoelectric switch 45 and the second photoelectric switch 45 and the second photoelectric switch 45 may be provided. Switch 46. In this case, the control unit 3 only determines whether the distance between the mobile device 5 and the inspected vehicle 6 is a predetermined distance through the conduction and disconnection of the first photoelectric switch 45 and the second photoelectric switch 46. When the distance deviates from the predetermined distance, the control unit 3 drives the direction control device 4 to change the moving direction of the moving device 5, thereby adjusting the distance to the predetermined distance.

In addition, in the direction correction device according to the second embodiment of the present invention, the first photoelectric switch 45 and the second photoelectric switch 46 are arranged side by side on one side of the moving device 5 . However, for those skilled in the art, the arrangement of the first photoelectric switch 45 and the second photoelectric switch 46 is not limited to the above-mentioned forms, and can be arranged in any suitable position. In addition, the number of photoelectric switches is not limited to two, any suitable number can be set.

A first preferred embodiment of the directional control device 4 is described below with reference to FIGS. 5-8 . As shown in Figures 5 and 6, the direction control device 4 includes a steering wheel 13 and an actuator 14 that control the moving direction A of the mobile device 5. For example, the steering wheel 13 can be a steering wheel of a scanning car, and the actuator 14 is located The rear side of the passenger seat S (for example, mounted on the side wall of the cab, which will be described in detail later) and extends from one side of the seat S to the steering wheel 13 so as to be connected with the steering wheel 13.

The actuator 11 is detachably connected to the steering wheel 13 and is driven by the drive circuit 12 of the control unit 3 so as to drive the steering wheel 13 to rotate so as to control the moving direction A of the mobile device 5 .

Furthermore, the direction control device 4 further includes a connection mechanism 18 , one end of which is connected to the actuator 14 , and the other end is detachably connected to the steering wheel 13 .

More specifically, the connecting mechanism 18 includes a connecting rod 19 , a mounting plate 20 , a joint bearing 21 , and a strut 22 .

The mounting plate 20 is detachably fixed to the outer periphery of the steering wheel 13 by, for example, bolts. As shown in FIG. 7 , the strut 22 is mounted on the upper surface of the mounting plate 20 , and one end of the connecting rod 19 is connected with the strut 22 through a joint bearing 21 so as to be able to rotate relative to the strut 22 . A nut 23 is disposed on the top of the strut 22 , and the nut 23 positions the connecting rod 19 on the strut 22 . The other end of the connecting rod 19 is hinged with the actuator 14 through a pin 24 and locked with a nut 25 .

Preferably, the direction correction device 100 according to this embodiment further includes a support plate 27, for example, the support plate 27 is installed on the side wall at the rear of the cab of the scanning vehicle. The bracket 26 is installed on the support plate 27, and the actuator 14 (for example, the actuator 14 is a worm and gear transmission mechanism driven by a motor, a hydraulic cylinder, or an air cylinder, which will be described in detail below) is installed on the bracket 26 through a cross block 28 superior. Said cross piece 28 and bracket 26 are hinged so as to form a universal joint so that the actuator 14 can rotate relative to the bracket 26 .

More preferably, a protection switch 29 is installed on the support plate 27 , and a pressure plate 30 is installed at the rear end (left side in FIGS. 5 and 6 ) of the universal joint formed by the cross piece 28 and the bracket 26 . When the actuator 14 is separated from the steering wheel 13 and erected, the pressure plate 30 hits the protection switch 29, so that the actuator 14 is de-energized and stops operating, as shown in FIG. 8 . Conversely, when the actuator 14 falls down and engages with the steering wheel 13, the pressure plate 30 hits the protection switch 29, thereby turning on the power supply of the actuator 14, so that the actuator 14 can operate, as shown in FIGS. 5 and 6 .

Preferably, the actuator 14 includes a motor 15 driven by a drive circuit 12, a worm gear 16 connected to the output shaft of the motor 15, and a worm 17 engaged with the worm gear 16, the worm 17 can be rotatably and detachably connected to the steering wheel 13 Joints may also be connected via the connection mechanism 18 as described above. More specifically, the worm 17 is rotatably connected with one end of the connecting rod 19 of the connecting mechanism 18, however, in order to save cost, the worm 17 can be made shorter, and a telescopic sleeve is set between the worm 17 and the connecting rod 19 (not shown), when the worm 17 rotates, the telescopic sleeve extends or shrinks, so as to drive the connecting rod 19 to move and thereby drive the steering wheel 13 to rotate.

The driving circuit 12 drives the motor 15 according to the driving signal of the processor 10, so that the worm wheel 16 rotates, drives the worm 17 to rotate and move, and the worm drives the connecting rod 19 to move to turn the steering wheel 13, thereby correcting the moving direction A of the moving device 5.

Those of ordinary skill in the art can understand that the actuator 14 according to the present invention is not limited to the form of the motor and worm gear mechanism described in the above-mentioned embodiments. Optionally, the actuator 14 can be a hydraulic cylinder, and the hydraulic cylinder The cylinder is driven by the control unit and its lever is connected to a connecting mechanism such as a connecting rod 19 to drive the steering wheel 13 to rotate according to the deviation between the moving direction A and the predetermined direction B. Furthermore, the above-mentioned hydraulic cylinders may also be replaced by air cylinders.

Operations of the actuators in the form of hydraulic cylinders and air cylinders are similar to those of the actuators in the first embodiment described above, and thus their detailed descriptions are omitted for simplicity.

The second embodiment of the direction control device 4 will be described below with reference to FIGS. 9-12 . As shown in FIGS. 9 and 10 , FIG. 9 shows a schematic structural diagram of a direction control device 4 according to a second embodiment of the present invention, and FIG. 10 is a top view of FIG. 9 . The direction control device 4 according to the second embodiment of the present invention includes a steering wheel 13 , a transmission device 31 and a flexible traction member 32 . The transmission device 31 is driven by the control unit 3 (drive circuit 12 ), and the flexible traction member 32 goes around the steering wheel 13 , and then the two ends are respectively connected and wound on the transmission device 31 . Preferably, the flexible traction member 32 is a traction rope.

More specifically, the transmission device 31 includes a motor 33 driven by the drive circuit 12 of the control unit 3, a double output shaft reducer 34 driven by the motor 33, and two output shafts respectively connected to the double output shaft reducer 34. The first and second couplings 35a and 35b, the first and second reel shafts 36a and 36b connected to the output sides of the first and second couplings 35a and 35b, respectively, and the first and second reel 37a and 37b, the first and second reels 37a and 37b are mounted to the first and second reel shafts 36a and 36b, respectively.

It should be noted that if the rotation directions of the two output shafts (i.e. the first and second reels 37a and 37b) of the double output shaft speed reducer 34 are the same, the two ends of the traction rope 32 are respectively wound around the opposite directions at the second end. on the first and second reels 37a and 37b. Conversely, if the rotation directions of the two output shafts (i.e. the first and second reel 37a and 37b) of the double output shaft speed reducer 34 are opposite, the two ends of the traction rope 32 are wound around the first and the second reels in the same direction respectively. Two reels 37a and 37b.

More preferably, the transmission device 31 further includes first and second support bases 38a and 38b, the first and second support bases 38a and 38b respectively support the first and second reel shafts 36a and 36b, and the first and second reel shafts 36a and 36b are respectively supported. The wheels 37a and 37b are located in the first and second support seats 38a and 38b, respectively. The first and second overrunning clutches 39a and 39b are installed in the first and second couplings 35a and 35b, respectively, and are preferably internal ratchet overrunning clutches.

Furthermore, first and second adjusting devices 40a and 40b are installed on the first and second supporting bases 38a and 38b respectively, for adjusting the tension of the pulling rope 32 . Preferably, the first and second adjusting means 40a and 40b are in the form of adjusting rods, and the two ends of the flexible rope 32 are respectively passed through the first and second adjusting rods 40a and 40b, and then wound around the first and second adjusting rods in opposite directions. Two reels 37a and 37b.

Preferably, a U-shaped groove is provided on the outer circumference of the steering wheel 13, and the traction rope 32 is engaged in the above-mentioned U-shaped groove, and is fixed by a clip 41 and a screw 42 to prevent the traction rope 32 from breaking away from the U-shaped groove and Slip inside the U-shaped groove. In the non-working state, for example, when the mobile scanning system needs to be moved from one working place to another working place, the traction rope 32 can be disengaged from the U-shaped groove and driven by the driver. The transmission device 31 is preferably arranged behind the seat S (the right side in FIG. 9 ) in the cab, so that the driver's driving will not be affected after the traction rope 32 is separated from the steering wheel 13 .

When the moving direction A of the moving device 5 deviates from the predetermined direction B, the driving circuit 12 of the control unit 3 sends a driving signal to the motor 33 of the driving device 31, and the motor 33 drives the double output shaft reducer 34 to rotate, thereby driving the first and second The reels 37a and 37b are rotated by an amount corresponding to the deviation value, whereby the pulling rope 32 rotates the steering wheel 13, correcting the moving direction A of the moving device 5 to the predetermined direction B.

The method for correcting the direction deviation of the mobile radiation inspection system during scanning radiation inspection by using the direction correction device of the present invention will be described below with reference to FIG. 15, wherein the direction control device is the first direction control device shown in FIGS. Two examples. However, those skilled in the art will understand that the following description of the direction correcting device is also applicable to the case of the first embodiment in which the direction control device is utilized.

Fig. 15 is a schematic flowchart of a method for correcting a direction according to the present invention.

As shown in Figure 15, the first and second distance detectors 2a and 2b detect the first and second distances L1 and L2 of the reference part 1 to the moving device 5, and generate the first and second distance detection signals, and simultaneously the first and second distance detection signals The first and second distance detection signals are transmitted to the control unit 3 (step S1).

The A/D converter 8 of the control unit 3 converts the first and second distance detection signals from analog signals into digital signals (step S2), and then the first and distance detection signals in the form of digital signals are "electrically switched" by the signal isolator 9. —optical-electrical” conversion, and then, the first and second distance detection signals are transmitted from the signal isolator 9 to the single-chip microcomputer 10 (step S3). The single-chip microcomputer 10 uses the first and second distance detection signals to determine whether the moving direction A deviates from the predetermined direction B (step S4), for example, by comparing the difference or ratio of the first and second distances to determine whether the moving direction A deviates and the deviation direction. For example, if L1 is greater than L2, then it is determined that the moving direction A deviates to the right in Fig. For example, if the deviation value is negative, the moving direction A deviates clockwise relative to the predetermined direction B; otherwise, if the deviation value is positive, the moving direction A deviates counterclockwise relative to the predetermined direction B. For another example, if the deviation value is greater than 1, the moving direction A deviates clockwise from the predetermined direction B; otherwise, if the deviation value is less than 1, the moving direction A deviates counterclockwise from the predetermined direction B.

The driving signal from the single-chip microcomputer 10 is then transmitted to the signal driver 11, and the signal driver 11 amplifies the driving signal from the single-chip microcomputer 10 and transmits it to the driving circuit 12 (step S5).

Then, the drive circuit 12 drives the motor 33 of the direction control device 4 to rotate, for example, the drive motor 33 rotates counterclockwise by an angle corresponding to the deviation value, and the motor 33 drives the first and second reels 37a and 37b to rotate, so that one end of the traction rope 32 is wound For example, on the first reel 37a, and the other end of the traction rope 32 is unwound from, for example, the second reel 37b, thereby driving the steering wheel 13 to rotate an angle corresponding to the deviation value, and the moving direction A of the mobile device 5 is corrected to the predetermined direction B (step S6).

When the moving direction A coincides with the predetermined direction B, the flow ends (step S7). Otherwise, the process returns to step S1.

Similarly, if the first distance L1 is less than the second distance L2, it means that the moving direction A deviates from the predetermined direction B to the left in FIGS. , which is similar to the operation of correcting the above-mentioned right deviation, and will not be described in detail here.

It should be noted that although it is shown in FIG. 15 that if the moving direction A coincides with the predetermined deviation direction B, the process ends. However, the judgment of whether the moving direction A deviates from the predetermined direction B can be performed in real time, that is, the first and second distance detectors 2a and 2b detect the first and second distances L1 and L2 in real time. Alternatively, for example, when using the reference member 1 shown in FIG. 3, the first and second distance detectors 2a and 2b intermittently detect the first and second distances L1 and L2, thereby periodically determining the direction of movement A Whether to deviate from the predetermined direction B.

It should be noted that if the control unit 3 (single-chip microcomputer 10 ) determines that the moving direction A does not deviate from the predetermined direction B according to the first and second distance detection signals, the control unit may not transmit the driving signal to the direction control device 4 . In other words, it can also be said that the drive signal (drive current) transmitted from the control unit 3 to the direction control device 4 is zero, which means there is no deviation. Therefore, those skilled in the art can understand that the control unit 3 controls the direction control device 4 in real time and periodically to correct the moving direction A (when there is no deviation, the required correction amount is zero).

In addition, those skilled in the art can understand that a predetermined threshold can be set for the deviation between the moving direction A and the predetermined direction B, and only when the absolute value of the deviation is greater than the predetermined threshold, the control unit 3 controls the direction The control device 4 corrects the moving direction of the moving device 5 .

The mobile radiation inspection system proposed according to another aspect of the present invention includes the above-mentioned direction deviation correction device. Other components of the mobile radiation inspection system, such as radiation sources, detector arrays arranged on extendable and retractable arms, imaging systems, control systems, etc., are similar to those in the prior art, and the above components can be integrated On the mobile device 5, a scanning vehicle is thus formed. For the sake of brevity, other components and operations of the mobile radiation inspection system will not be described in detail here.

While embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by The appended claims and their equivalents are defined.

Claims (27)

1. A direction correction device for a mobile radiation inspection system with a mobile device, comprising: a direction detection device, the direction detection device detects the moving direction of the mobile device and generates a detection signal indicating the moving direction; a direction control device for controlling the direction of movement of the mobile device; and a control unit that calculates a deviation value between the moving direction and a predetermined direction based on the detection signal received from the direction detecting device, and drives the direction control device based on the deviation value so as to correct the moving direction to a predetermined direction direction, Wherein the direction detection device includes at least one photoelectric switch, wherein the control unit controls the distance between the mobile device and the inspected object to a predetermined distance according to the signal received from the at least one photoelectric switch. 2. The direction deviation correction device according to claim 1, wherein said direction detection means comprises first and second distance detectors, said first and second distance detectors generate first and second distance detection signals respectively, Wherein the control unit calculates the deviation value according to the first and second distance detection signals. 3. The direction correcting apparatus according to claim 2, wherein said first and second distance detectors detect first and second distances of said mobile device to an object to be inspected. 4. The direction correcting apparatus according to claim 3, further comprising a reference member, wherein said first and second distance detectors respectively detect a first distance and a second distance of said moving device from said reference member. 5. The direction correction device according to claim 1, wherein said direction control device comprises: a steering wheel to control the direction of movement of the mobile device; and An actuator detachably engaged with the steering wheel and driven by the control unit to drive the steering wheel to rotate to control the direction of movement of the mobile device. 6. The direction correcting apparatus according to claim 5, wherein the direction control device further comprises a link mechanism, one end of which is connected to the actuator and the other end is detachably engaged with a steering wheel of the mobile device. 7. The direction correction device according to claim 6, wherein the connecting mechanism comprises: a connecting rod, one end of which is connected to the actuator; A strut, the other end of the connecting rod is connected to the strut through a joint bearing, and a nut for positioning the connecting rod is provided at the top of the strut; A mounting plate, the struts are mounted to the top surface of the mounting plate, and the sides of the mounting plate are detachably joined to the outer periphery of the steering wheel to drive the steering wheel to rotate. 8. The direction correction device according to claim 7, said direction control device further comprising a bracket and a cross block, wherein the cross block is hinged with the bracket so as to form a universal joint, and the actuator is mounted on the cross block through the cross block on the stand. 9. The direction correction device according to claim 8, said direction control device further comprising: a support plate, the bracket is mounted on the support plate; a guard switch mounted on the support plate; and A pressure plate connected to the gimbal such that when the actuator and linkage together are disengaged from the steering wheel, the pressure plate strikes the guard switch to de-energize the actuator. 10. The direction correcting device of claim 6, wherein the actuator comprises: a motor driven by the control unit; a worm gear connected to the output shaft of the motor; and a worm meshed with the worm wheel, and the axial end of the worm is connected with the connecting mechanism. 11. The direction correction device according to claim 5, wherein said direction control device comprises: a transmission driven by the control unit; and A flexible traction member, the two ends of the flexible traction member bypass the steering wheel and are respectively connected to the transmission device. 12. The direction correcting device according to claim 11, wherein the flexible traction member is a traction rope. 13. The direction correction device according to claim 12, wherein the traction rope is detachably engaged in the groove of the outer circumference of the steering wheel through a clip and a screw. 14. The direction correction device according to claim 13, wherein said transmission means comprises: motors driven by the control unit; and A double output shaft reducer driven by a motor, the two ends of the traction rope are respectively connected with the two output shafts of the double output shaft reducer. 15. The direction correction device according to claim 14, wherein said transmission further comprises: first and second shaft couplings, the input sides of the first and second shaft couplings are respectively connected to the two output shafts of the reducer; first and second reel shafts connected to the output sides of the first and second couplings and supported by the first and second support seats, respectively; and First and second reels, the first and second reels are respectively mounted on the first and second reel shafts, wherein the two ends of the traction rope are respectively wound on the first and second reels. 16. The direction correcting device according to claim 15, wherein the transmission device further comprises first and second adjustment devices, the first and second adjustment devices are used to adjust the tension of the pulling rope. 17. The direction correcting apparatus according to claim 16, wherein the transmission further comprises first and second overrunning clutches disposed within the first and second couplings, respectively. 18. The direction deviation correcting apparatus according to claim 4, wherein said reference member comprises an integral flat member arranged in parallel with said predetermined direction. 19. The direction deviation correcting apparatus according to claim 4, wherein the reference member comprises a plurality of flat plate segments spaced apart from each other in the predetermined direction and arranged in alignment. 20. A mobile radiation inspection system comprising the direction correction device according to claim 1. 21. A direction correction method for correcting the moving direction of a mobile radiation inspection system, wherein the mobile radiation inspection system has a moving device, the direction correction method comprising: Step 1) detecting the moving direction of the mobile device and generating a detection signal indicating the moving direction; Step 2) calculating a deviation value between the moving direction and a predetermined direction based on the detection signal and automatically correcting the moving direction to a predetermined direction according to the deviation value, Step 3) providing at least one photoelectric switch, and Step 4) Using the at least one photoelectric switch to automatically control the distance between the mobile device and the object to be inspected to a predetermined distance. 22. The direction correction method according to claim 21, wherein: Said step 1) includes detecting first and second distances between said mobile device and the inspected object, so as to generate first and second distance detection signals; and The step 2) calculates the deviation value between the moving direction of the mobile device and the predetermined direction according to the first and second distance detection signals, and automatically corrects the moving direction to the predetermined direction according to the deviation value. 23. The direction correction method according to claim 21, further comprising: providing a reference part after step 2) and before step 3); in: Said step 1) includes detecting first and second distances between said mobile device and a reference member, so as to generate first and second distance detection signals; and The step 2) calculates the deviation value between the moving direction of the mobile device and the predetermined direction according to the first and second distance detection signals, and automatically corrects the moving direction to the predetermined direction according to the deviation value. 24. The direction correction method according to claim 22 or 23, wherein the first and second distances are detected by a laser ranging sensor. 25. The direction deviation correction method according to claim 22, wherein calculating the deviation value and correcting the moving direction of the mobile radiation inspection system according to the deviation value are completed by using a control unit and a direction control device, wherein the direction control device is used to control the moving direction of the mobile radiation inspection system, and The control unit includes: an analog/digital converter converting the first and second distance detection signals from analog signals to digital signals; a processor, the processor calculates the deviation value according to the first and second distance detection signals converted into digital signals so as to generate a driving signal corresponding to the deviation value; a signal driver that receives and increases the drive signal from the processor; and A drive circuit that drives the direction control device based on the increased drive signal received from the signal driver so as to correct the direction of movement of the mobile device. 26. The direction deviation correction method according to claim 25, wherein the control unit further comprises a signal isolator, and the signal isolator is connected between the output of the analog/digital converter and the input of the processor for isolating the input Input signals to it and output signals from it. 27. The direction correction method according to claim 26, wherein the signal isolator comprises a photoelectric isolator.

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