Multifunctional examination terminal device

Abstract

The utility model relates to the technical field of anti-cheating equipment, and particularly discloses a multifunctional examination terminal device which comprises a metal detection unit, a current detection unit, a main controller, a display screen, a loudspeaker, a camera, an image processing module, a card reader and a wireless communication module. The current detection unit detects mobile phone wireless earphone contraband articles and the like, reminds through display of detection content of the display screen and voice broadcast of the loudspeaker, checks identity information of examinees through the camera, the image processing module and the card reader, and records videos in the checking process through the camera. Alarm information is sent through the wireless communication module, the problems that in the prior art, the detection function and the alarm mode of a handheld examination affair detector are single, and prohibited goods such as metal objects and mobile phones which trigger alarms cannot be effectively distinguished are solved, and examination affair checking work efficiency is improved while examination fairness is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of anti-cheating equipment, and particularly relates to a multifunctional examination terminal device. Background Art

[0002] In examination work, handheld detectors are often needed to check whether candidates are carrying prohibited items, such as mobile phones, keys, and iron or metal stationery. Handheld detectors for examinations are a very effective anti-cheating tool that helps ensure the fairness of the exam.

[0003] The existing handheld detectors for examinations have relatively simple functions when in use. Before students enter the examination room, they first need to verify the identity of the examinee. Usually, the invigilator uses the naked eye to compare the examinee's appearance with the ID card for judgment, or uses image recognition equipment for verification, which prolongs the investigation time. In addition, the existing handheld detectors for examinations mainly detect metal materials in items prohibited from being brought into the examination room and issue sound and light alarms. When in use, materials such as belt buckles and metal zippers will trigger alarms, and the alarm sound and alarm method are relatively simple, and it is impossible to effectively distinguish prohibited items. The back-end command personnel cannot obtain the investigation results in time. In actual operation, in order to check efficiency, invigilators usually judge such situations as simple metal and allow examinees to enter the examination room. There is a risk of cheating equipment flowing into the examination room, affecting the fairness of the examination.

[0004] In addition, there is a lack of effective monitoring when invigilators use existing handheld detectors for inspection. If invigilators do not conduct careful inspections in order to increase the inspection time, there is a risk of prohibited items being brought into the examination room, affecting the fairness of the examination.

[0005] In view of this, the utility model proposes a multifunctional examination terminal device to solve the above technical problems. Utility Model Content

[0006] The purpose of the utility model is to provide a multifunctional examination terminal device to overcome the defects of the prior art, realize the identification of examinees, identify mobile phones and pure metal objects and distinguish and alarm, and remotely send the screening results.

[0007] To achieve the above purpose, the utility model provides a multifunctional examination terminal device, comprising:

[0008] A metal detection unit, the metal detection unit comprising an oscillation coil, an oscillation circuit and a comparator, the oscillation coil is connected to an output end of the oscillation circuit, the inverting end of the comparator is connected to an output end of the oscillation circuit, and the non-inverting end of the comparator is connected to a reference voltage circuit;

[0009] A current detection unit, wherein the current detection unit includes two current detectors, and the two current detectors include a magnetic focusing ring, an AMR magnetic sensor, a PWM module and a signal processing circuit. The AMR magnetic sensor is installed on the magnetic focusing ring, and the output end of the PWM module is connected to the input end of the AMR magnetic sensor, and the output end of the AMR magnetic sensor is connected to the input end of the signal processing circuit;

[0010] A main controller, a display screen, a speaker, a camera, an image processing module, a card reader and a wireless communication module, wherein the output ends of the comparator and the signal processing circuit are respectively connected to the main controller, the camera is connected to the image processing module, the image processing module is connected to the main controller, and the display screen and the speaker are respectively connected to the main controller.

[0011] Preferably, in the above technical solution, it also includes a human detection module, a vibration sensor and a timing control circuit, and the human detection module, the vibration sensor and the timing control circuit are respectively connected to the main controller.

[0012] Preferably, in the above technical solution, it further includes a shell and an elastic buckle, the elastic buckle is telescopically arranged on the top of the shell, and the top of the shell is provided with a groove.

[0013] Preferably, in the above technical solution, it also includes a base, a rotating seat is provided on the top of the base, the camera can be horizontally rotatable on the rotating seat, and a rotating shaft and two positioning holes corresponding to the elastic buckle are provided on both sides of the base. The base can be longitudinally rotated in the groove through the rotating shafts on both sides.

[0014] Preferably, in the above technical solution, it also includes a knob for adjusting the sensitivity of the metal detection unit, and the knob is connected to the main controller.

[0015] Preferably, in the above technical solution, the signal processing circuit includes a differential amplifier, a high-pass filter, a phase-sensitive detector, an integrator and a high-speed ADC module, the input end of the differential amplifier is connected to the AMR magnetic sensor, the output end of the differential amplifier is connected to the input end of the high-pass filter, the output end of the high-pass filter is connected to the phase-sensitive detector, the output end of the phase-sensitive detector is connected to the input end of the integrator, the output end of the integrator is connected to the input end of the high-speed ADC module, and the output end of the high-speed ADC module is connected to the main controller.

[0016] Preferably, in the above technical solution, the current detection unit further includes a current source, one output end of the integrator is connected to the current source, and an output end of the current source is connected to the AMR magnetic sensor.

[0017] Preferably, in the above technical solution, it also includes a lithium battery and a voltage monitoring circuit, the output end of the lithium battery is connected to the input end of the timing control circuit, the output end of the timing control circuit is connected to the input end of the voltage monitoring circuit, and the output end of the voltage monitoring circuit is connected to the main controller.

[0018] Compared with the existing technology, the present invention has the following beneficial effects:

[0019] 1. The utility model detects the DC magnetic field signal formed by the current signal in the mobile phone through the AMR magnetic sensor in the current detection unit. The signal processing circuit amplifies and filters the voltage signal output by the AMR magnetic sensor and outputs it to the main controller for detection. The main controller determines whether the mobile phone exists by detecting the output of the AMR magnetic sensor, and displays it on the display screen and plays a voice alarm on the speaker. The metal detection and current detection functions are switched by the switch, which realizes the effective distinction between mobile phones and other pure metal objects. The candidate's ID card is read by the card reader, the camera collects the portrait data, the image processing module recognizes the portrait data taken by the camera and outputs the result, the screening process is recorded and stored, and the alarm information is sent through the wireless communication module. The above technical means solve the problem of the single function of the existing handheld detectors for examination affairs, improve the screening efficiency and ensure the fairness and justice of the examination.

[0020] 2. The utility model determines the working state of the device by a combination of a human body detection module detecting whether a human hand is holding the device and a vibration sensor detecting the action of a human body waving the device, and puts the device into sleep or shuts down through a timing control circuit. This is different from the prior art which simply uses a vibration sensor to detect the working state of the handheld examination detector and puts the handheld examination detector into sleep or shuts down at a scheduled time. In the process of transportation or storage, a handheld examination detector that is forgotten to be shut down may be repeatedly started up by mistake due to vibration, resulting in power consumption of the device and affecting the next use of the device. This utility model has higher reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0022] Figure 2 It is a schematic diagram of the internal structure of the utility model.

[0023] Figure 3 It is a schematic diagram of the top structure of the shell of the utility model.

[0024] Figure 4 It is a schematic diagram of the overall electrical principle structure of the utility model.

[0025] Figure 5This is a schematic diagram of the electrical principle structure of the current detector of the utility model.

[0026] Figure 6 This is a schematic diagram of the electrical principle structure of the metal detection unit of the utility model.

[0027] In the figure: 1 - housing, 2 - speaker, 3 - human body recognition module, 4 - switch, 5 - display screen, 6 - current detector, 7 - AMR magnetic sensor, 8 - magnetic focusing ring, 9 - camera, 10 - knob, 11 - base, 12 - rotating seat, 13 - positioning hole, 14 - rotating shaft, 15 - groove, 16 - elastic buckle, 100 - main controller, 101 - image processing module, 102 - card reader, 103 - vibration sensor, 104 - wireless communication module, 105—metal detection unit, 106—current detection unit, 107—lithium battery, 108—voltage monitoring circuit, 109—timing control circuit, 200—PWM module, 201—differential amplifier, 202—high-pass filter, 203—phase-sensitive detector, 204—integrator, 205—high-speed ADC module, 206—current source, 300—oscillation circuit, U1—comparator, L1—oscillation coil, R1—first resistor, R2—second resistor. DETAILED DESCRIPTION

[0028] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0029] like Figure 1 and Figure 4As shown, the multifunctional examination terminal device in this embodiment includes a housing 1, a metal detection unit 105, a current detection unit 106, a display screen 5, a speaker 2, a camera 9, an image processing module 101, a card reader 102, a main controller 100 and a wireless communication module 104. The metal detection unit 105 includes an oscillation coil L1, an oscillation circuit 300 and a comparator U1. An output end of the oscillation circuit 300 is connected to the oscillation coil L1, an input end of the oscillation circuit 300 is connected to the main controller 100, and an output end of the oscillation circuit 300 is connected to the comparator U1. The inverting end of the comparator U1 is connected, and the in-phase end of the comparator U1 is connected to a reference voltage circuit. The reference voltage circuit is composed of a first resistor R1 and a second resistor R2 connected to form a voltage divider circuit, wherein the second resistor R2 is an adjustable resistor, and its adjustment end is connected to a knob 10. The output end of the comparator U1 is connected to the main controller 100. By rotating the knob 10, the resistance value of the second resistor R2 is changed, thereby changing the voltage across the second resistor R2, so that the reference voltage input to the in-phase end of the comparator U1 changes, thereby realizing the adjustment of the detection sensitivity of the metal detection unit 105. The current detection unit 106 includes two current detectors 6, and the current detector 6 includes a magnetic ring 8, an AMR magnetic sensor 7, a PWM module 200 and a signal processing circuit. The AMR magnetic sensor 7 is glued to the magnetic ring 8, and the output end of the PWM module 200 is connected to the input end of the AMR magnetic sensor 7, and the output end of the AMR magnetic sensor 7 is connected to the input end of the signal processing circuit, and the output end of the signal processing circuit is connected to the main controller 100. The display screen 5 and the speaker 2 are respectively connected to the main controller 100, the camera 9 is connected to the image processing module 101, and the image processing module 101 is connected to the main controller 100. In this embodiment, the model of the main controller 100 can be STM32F423VHT6, and the model of the wireless communication module 104 can be a UWB wireless communication module.

[0030] When collecting portraits, first rotate the camera 9 out of the groove 15, then rotate the camera 9 horizontally so that the lens of the camera 9 rotates to the side of the shell 1 with the display screen 5, put the candidate's ID card in the identification area of ​​the card reader 102, the candidate faces the camera 9, the card reader 102 reads the ID card information, and remotely downloads the candidate's portrait picture matching the ID card information read by the card reader 102 from the background server through the wireless communication module 104, and sends it to the image processing module 101. The image processing module 101 collects the image data of the camera 9 and compares it with the remotely downloaded candidate portrait picture, and outputs the result to the main controller 100. The main controller 100 drives the display screen 5 to display the entire candidate identity recognition process. The utility model can complete the inspection of prohibited items and the verification of the candidate's identity information, effectively improving the inspection efficiency. When recording the screening process, the camera 9 is rotated to the other side of the shell 1 without the display screen 5, and the camera 9 shoots the screening process. The image processing module 101 is provided with a memory storage module, and the image data is stored through the memory storage module in the image processing module 101, which further ensures the fairness of the examination.

[0031] Continue to refer Figure 1 and Figure 5The signal processing circuit of the current detector 6 includes a differential amplifier 201, a high-pass filter 202, a phase-sensitive detector 203, an integrator 204 and a high-speed ADC module 205. The input end of the differential amplifier 201 is connected to the AMR magnetic sensor 7, the output end of the differential amplifier 201 is connected to the input end of the high-pass filter 202, the output end of the high-pass filter 202 is connected to the phase-sensitive detector 203, the output end of the phase-sensitive detector 203 is connected to the input end of the integrator 204, the output end of the integrator 204 is connected to the input end of the high-speed ADC module 205, and the output end of the high-speed ADC module 205 is connected to the main controller 100. According to the principle of electromagnetic induction, the current existing in the electronic components in the mobile phone will form a DC magnetic field on the surface of the electronic components. Even if the mobile phone is in the off state, some electronic components are in the working state and will also generate a DC magnetic field. The DC magnetic field can be collected by the AMR magnetic sensor 7. In this embodiment, the AMR magnetic sensor 7 uses the KMZ51 single-axis AMR sensor chip, which is mainly composed of a Wheatstone bridge composed of four magnetic resistors, a set coil and a compensation coil. The magnetic field changes are collected through the four magnetic resistors and converted into an AC voltage signal for output. The set coil of the AMR magnetic sensor 7 is connected to the PWM module 200. The PWM module 200 is used to generate a flip pulse signal to the set coil to drive the AMR magnetic sensor 7 to work. The magnetic focusing ring 8 is used to gather and amplify the DC magnetic field generated by the electronic components for collection by the AMR magnetic sensor 7. The PI compensation circuit is composed of the current source 206 and the integrator 204, which is used to generate a compensation current to input to the compensation coil, so that the compensation coil generates a compensation magnetic field to eliminate the hysteresis effect of the magnetic focusing ring 8 and the error caused by the temperature drift of the AMR magnetic sensor 7, and improve the linearity of the output result of the AMR magnetic sensor 7. The differential amplifier 201 is used to amplify the weak voltage signal output by the AMR magnetic sensor 7, the high-pass filter 202 is used to eliminate the DC bias voltage of the magnetoresistive bridge in the AMR magnetic sensor 7, and the phase-sensitive detector 203 is used to demodulate the AC voltage signal output by the AMR magnetic sensor 7 after filtering by the high-pass filter 202 into a DC voltage signal, thereby improving the signal-to-noise ratio of the output signal. At the same time, a phase-locked amplifier is formed by connecting the phase-sensitive detector 203 with the integrator 204. The integrator 204 further rectifies and filters the output DC voltage signal of the phase-sensitive detector 203. The high-speed ADC module 205 collects the DC voltage signal of the integrator 204 and converts it into a digital signal for the main controller 100 to receive and process, thereby completing the detection of the mobile phone. In this embodiment, the chip model selected for the phase-sensitive detector 203 is a high-precision demodulator of AD630, the operational amplifier chip model used for the high-pass filter 202 is AD620, the operational amplifier chip model selected for the integrator 204 and the differential amplifier 201 is OP37, and the high-speed ADC module 205 is LTC2378.

[0032] Continue to refer Figure 4 The multifunctional examination terminal device in this embodiment also includes a human body recognition module 3, a vibration sensor 103, a timing control circuit 109, a lithium battery 107 and a voltage monitoring circuit 108. The human body recognition module 3 is arranged at the handle of the housing 1 to detect whether someone is holding the terminal device. The output ends of the human body recognition module 3 and the vibration sensor 103 are respectively connected to the main controller 100, the input control end of the timing control circuit 109 is connected to the main controller 100, the input end of the timing control circuit 103 is connected to the output end of the lithium battery 107, the output end of the timing control circuit 109 is connected to the input end of the voltage monitoring circuit 108, and the output end of the voltage monitoring circuit 108 is connected to the main controller 100. The voltage monitoring circuit 108 is used to monitor the battery voltage of the lithium battery 107 and output it to the main controller 100 for receiving. When the voltage is too low, the main controller 100 drives the display screen 5 to display a reminder and drives the speaker 2 to broadcast a voice reminder. The timing control circuit 109 is equipped with a timer and a relay switch. When the human recognition module 3 detects that someone is holding the terminal device and the vibration sensor 103 does not detect that the terminal device is being waved, the timing control circuit 109 starts timing. When the timing time reaches the set threshold, the main controller 100 outputs a control signal to put the terminal device into sleep. When the vibration sensor 103 detects that the terminal device is being waved, the main controller 100 outputs a control signal to wake up the terminal device and put it into operation. When the human body recognition module 3 does not detect that someone is holding the terminal device, timing is performed through the timing control circuit 109. When the timing time reaches the set threshold and the human body recognition module 3 still does not detect that someone is holding the terminal device, the main controller 100 drives the relay switch in the timing control circuit 109 to disconnect, so that the lithium battery 107 is removed from the system, the terminal device is shut down, and the power of the terminal device is saved. Compared with the prior art, only a vibration sensor 109 is used to perform the use status of the handheld examination detector to shut down or put the handheld examination detector into sleep mode, which may cause the handheld examination detector that is forgotten to be shut down to be awakened again due to bumps or vibrations from the external environment during storage or transportation, resulting in the handheld examination detector that is forgotten to be shut down being unable to be properly shut down, thereby wasting the power of the handheld examination detector and affecting the use of the next examination work. The utility model has higher reliability.

[0033] Continue to refer Figures 1 to 3The multifunctional examination terminal device in this embodiment also includes a switching switch 4, an elastic buckle 16 and a base 11. A groove 15 is provided on the top of the shell 1. A spring is provided at one end of the elastic buckle 16. The elastic buckle 16 is retractably provided on the top of the shell 1 and extends from the side of the groove 15. A rotating seat 12 is provided on the top of the base 11. The camera 9 is installed on the rotating seat 12 to realize the rotation connection between the camera 9 and the base 11 through the rotating seat 12. A rotating shaft 14 and two positioning holes 13 corresponding to the elastic buckle 16 are provided on the side of the base 11. The rotating shaft 14 is rotatably fixed on both sides of the groove 15. The base 11 is longitudinally rotated in the groove 15 through the rotating shaft 14. The base 11 is fixed by the clamping of the elastic buckle 16 and the positioning holes 13, thereby realizing the extension or retraction of the camera 9 from the groove 15. When not in use, the camera 9 can be rotated and retracted into the groove 15 for protection. The switching switch 4 is connected to the main controller 100 for switching the metal detection or current detection function.

[0034] The utility model detects the mobile phone through the AMR magnetic sensor 7 in the current detection unit 106, detects the metal material through the metal detection unit 105, displays through the display screen 5 and plays the voice alarm through the speaker 2, and switches the metal detection and current detection functions through the switch 4, thereby effectively distinguishing the mobile phone from other pure metal objects. The card reader 102 reads the examinee's ID card, the camera 9 collects the portrait data, the image processing module 101 recognizes the portrait data taken by the camera 9 and outputs the result, the camera 9 takes pictures of the screening process, the image processing module 101 stores the image data, and sends the alarm information through the wireless communication module 104. The above technical means solve the problem of the single function of the existing handheld detector for examination affairs, improve the screening efficiency and ensure the fairness and justice of the examination.

[0035] The foregoing description of specific exemplary embodiments of the utility model is for the purpose of illustration and illustration. These descriptions are not intended to limit the utility model to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the utility model and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the utility model and various different options and changes. The scope of the utility model is intended to be limited by the claims and their equivalents.

Claims

1. A multifunctional examination terminal device, characterized in that: include: A metal detection unit, the metal detection unit comprising an oscillation coil, an oscillation circuit and a comparator, the oscillation coil is connected to an output end of the oscillation circuit, the inverting end of the comparator is connected to an output end of the oscillation circuit, and the non-inverting end of the comparator is connected to a reference voltage circuit; A current detection unit, wherein the current detection unit includes two current detectors, and the two current detectors include a magnetic focusing ring, an AMR magnetic sensor, a PWM module and a signal processing circuit. The AMR magnetic sensor is installed on the magnetic focusing ring, and the output end of the PWM module is connected to the input end of the AMR magnetic sensor, and the output end of the AMR magnetic sensor is connected to the input end of the signal processing circuit; A main controller, a display screen, a speaker, a camera, an image processing module, a card reader and a wireless communication module, wherein the output ends of the comparator and the signal processing circuit are respectively connected to the main controller, the camera is connected to the image processing module, the image processing module is connected to the main controller, and the display screen and the speaker are respectively connected to the main controller.

2. The multifunctional examination terminal device according to claim 1, characterized in that: It also includes a human body detection module, a vibration sensor and a timing control circuit, and the human body detection module, the vibration sensor and the timing control circuit are respectively connected to the main controller.

3. The multifunctional examination terminal device according to claim 1 is characterized in that: It also includes a shell and an elastic buckle, wherein the elastic buckle is telescopically arranged on the top of the shell, and a groove is arranged on the top of the shell.

4. The multifunctional examination terminal device according to claim 3 is characterized in that: It also includes a base, a rotating seat is provided on the top of the base, the camera can be horizontally rotated on the rotating seat, and a rotating shaft and two positioning holes corresponding to the elastic buckle are provided on both sides of the base. The base can be longitudinally rotated in the groove through the rotating shafts on both sides.

5. The multifunctional examination terminal device according to claim 1, characterized in that: It also includes a knob for adjusting the sensitivity of the metal detection unit, and the knob is connected to the main controller.

6. The multifunctional examination terminal device according to claim 1, characterized in that: The signal processing circuit includes a differential amplifier, a high-pass filter, a phase-sensitive detector, an integrator and a high-speed ADC module. The input end of the differential amplifier is connected to the AMR magnetic sensor, the output end of the differential amplifier is connected to the input end of the high-pass filter, the output end of the high-pass filter is connected to the phase-sensitive detector, the output end of the phase-sensitive detector is connected to the input end of the integrator, the output end of the integrator is connected to the input end of the high-speed ADC module, and the output end of the high-speed ADC module is connected to the main controller.

7. The multifunctional examination terminal device according to claim 6 is characterized in that: The current detection unit further includes a current source, one output end of the integrator is connected to the current source, and an output end of the current source is connected to the AMR magnetic sensor.

8. The multifunctional examination terminal device according to claim 2 is characterized in that: It also includes a lithium battery and a voltage monitoring circuit, wherein the output end of the lithium battery is connected to the input end of the timing control circuit, the output end of the timing control circuit is connected to the input end of the voltage monitoring circuit, and the output end of the voltage monitoring circuit is connected to the main controller.

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