Bionic device for mobile calibration of thermal imaging type screening instrument

Abstract

The invention discloses a bionic device for mobile calibration of a thermal imaging type screening instrument, and relates to the technical field of thermal imaging type screening instrument calibration, the bionic device comprises a mobile cart and a bionic head, a black body radiation source with effective emissivity of 0.98 is arranged in the bionic head, a black body cavity of the black body radiation source is located in the center of the forehead of the bionic head, and the black body cavity of the black body radiation source is located in the center of the forehead of the bionic head. A first heating coil and a second heating coil are wound on the outer side of the black body cavity; according to the method, the blackbody radiation source is embedded into the bionic human head, the method can be used for body temperature mode error calibration under the condition of screening instrument face recognition, the blackbody radiation source is provided with the uninterruptible power supply, when screening instruments at different positions are calibrated, blackbody radiation source power failure caused by position movement is avoided, and the calibration accuracy is improved. The waiting time required for restarting and stabilizing the blackbody radiation source is avoided, and the working efficiency of field calibration is improved. The device is placed on a movable trolley, field calibration movement is facilitated, and the labor intensity of calibration personnel is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of thermal imaging screening instrument calibration, and in particular to a bionic device for mobile calibration of a thermal imaging screening instrument. Background Art

[0002] The infrared human surface temperature rapid screening instrument, referred to as the screening instrument, is an instrument that focuses the infrared rays radiated from the human forehead surface skin onto the infrared detector through an optical system, and converts this information into human body temperature through electronic components. It uses infrared temperature measurement technology to quickly measure and convert the surface temperature of the human forehead. When the measured human surface temperature reaches or exceeds the preset warning temperature value, an alarm is issued for screening, thereby achieving the purpose of body temperature screening. The screening instrument has the characteristics of non-contact, fast, convenient, intuitive, and safe. It overcomes the shortcomings of traditional thermometers, forehead thermometers, spot thermometers, and ear thermometers that only measure individuals, are time-consuming, and are prone to cross-infection. It is very suitable for rapid temperature screening in places with large traffic such as airports, docks, stations, hospitals, and shopping malls.

[0003] Screening devices include point temperature type, multi-point type and thermal imaging type. Thermal imaging type screeners are usually equipped with special body temperature screening software, which has a built-in face detection module. It only measures the highest temperature value in the forehead area of ​​the face, which is displayed as the human body temperature measurement value after conversion by the software, shielding the high temperature source other than the face in the field of view of the screener to prevent false alarms. The face detection module uses 2D face recognition technology based on facial features.

[0004] At present, the calibration of screening instruments is usually carried out by professional metrological technicians in the calibration mode according to the national metrological technical specification "JJF 1107-2003 Calibration Specifications for Infrared Thermometers for Measuring Human Body Temperature". The laboratory error of the screening instrument is the difference between the temperature measured by the screening instrument in the calibration mode and the temperature of an absolute black body (effective emissivity is 1.00) under the specified ambient temperature, humidity and black body temperature conditions. The calibration mode of the screening instrument is set independently in its supporting software. The correction value obtained in the calibration mode has different effects on the measurement results of the body temperature mode due to the software algorithms of different manufacturers. Since the laboratory error is not the body temperature measurement error, it is very necessary to directly calibrate the measurement error of the screening instrument in the body temperature mode to more accurately reflect the measured human body temperature.

[0005] In addition, many entrances in public places are equipped with screening devices. Due to the long distance between the entrances, when calibrating on site, the metrologist needs to turn off the power of the blackbody radiation source after completing the calibration at one entrance, carry it to another entrance, and then turn on the blackbody radiation source again. The calibration work can only be started after the temperature reaches the set value and stabilizes. It takes a long time for the blackbody radiation source to reach a stable state again after being turned on, which limits the efficiency of on-site calibration. Summary of the invention

[0006] The purpose of the present invention is to solve the defects in the prior art and to propose a bionic device for mobile calibration of a thermal imaging screening instrument.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A bionic device for mobile calibration of a thermal imaging screening instrument comprises a mobile cart and a bionic human head. The bionic human head has a built-in blackbody radiation source with an effective emissivity of 0.98. The blackbody cavity of the blackbody radiation source is located at the center of the forehead of the bionic human head. A first heating coil and a second heating coil are wound around the outside of the blackbody cavity. The first heating coil is close to the opening of the blackbody cavity and covers 1 / 3 of the outer wall of the blackbody cavity. The second heating coil is far from the opening of the blackbody cavity and covers 2 / 3 of the outer wall of the blackbody cavity. The outsides of the first heating coil and the second heating coil are filled with thermal insulation cotton. A first thermometer and a second thermometer are embedded in the inner wall of the blackbody cavity, a temperature sensing point of the first thermometer is close to the opening of the blackbody cavity, and a temperature sensing point of the second thermometer is far from the opening of the blackbody cavity, the first heating coil is connected to a first power line, the second heating coil is connected to a second power line, the first power line and the second power line are respectively connected to the output ends of the first thermostat and the second thermostat, the first thermometer and the second thermometer are respectively connected to the input ends of the first thermostat and the second thermostat through a first extension line and a second extension line, and a positioning nut is provided on the bottom surface of the bionic head;

[0009] A lifting platform is arranged on the mobile cart, a hand wheel is arranged on the lifting platform, an uninterruptible power supply is placed under the lifting platform, a tilting platform and a support arm are rotatably arranged above the lifting platform, a card slot is opened on the bottom wall of the tilting platform close to one end of the support arm, the card slot matches the end of the support arm, the tilting platform is supported by the support arm, the bionic human head is placed on the tilting platform, the input end of the uninterruptible power supply is connected to the mains through a power cord, the first thermostat and the second thermostat of the blackbody radiation source are powered by a power bus, and the power bus is connected to the 220V AC output by the uninterruptible power supply.

[0010] This solution forms a dual-stage independent temperature control capability of the blackbody radiation source through the combination of the first heating coil, the first thermometer, the first extension line, the first temperature controller, and the second heating coil, the second thermometer, the second extension line, and the second temperature controller, effectively avoiding the phenomenon of low temperature in the opening section of the blackbody cavity due to convection heat dissipation of the external air, effectively ensuring the temperature uniformity of the blackbody cavity and the stability of the brightness temperature of the blackbody radiation source. After the two sections of temperature are stable and equal, they can be used for the calibration of the screening instrument.

[0011] Preferably, the temperature range of the blackbody radiation source is room temperature + 5°C - 40.0°C, and the first thermometer and the second thermometer are of Pt100 model. The brightness temperature of the blackbody radiation source should be traced back to the social public measurement standard every year, and the effective emissivity of the blackbody radiation source should be measured at least once every 3 years.

[0012] Preferably, the black body cavity is made of copper segments, the inner wall is coated with black paint with an emissivity of not less than 0.9, the aspect ratio of the cylindrical segment of the black body cavity is not less than 2, and the bottom of the black body cavity is a non-flat cone or anisotropic surface.

[0013] Preferably, the stroke of the lifting platform is adjusted to 0-45 cm by a hand wheel, the tilt angle range of the tilting platform is 0-60°, the tilting platform is a non-slip surface, the lifting platform is supported by a fixed partition, and the uninterruptible power supply is located below the fixed partition.

[0014] Preferably, the bionic human head can be fixed on a tripod via the positioning nut and used alone.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention embeds a blackbody radiation source into a bionic human head, which can be used for temperature mode error calibration in face recognition of the screening instrument, thereby solving the problem that the screening instrument can only recognize the temperature of the forehead of the face but cannot recognize the temperature of the blackbody radiation source in the body temperature mode. The effective emissivity of the blackbody cavity of the present invention is 0.98, which is consistent with the emissivity of the forehead of an adult. The reading of the screening instrument in the body temperature mode can be directly compared with the temperature of the blackbody radiation source, and the measurement error of the screening instrument in the body temperature mode can be calculated.

[0017] 2. The blackbody radiation source of the present invention is equipped with an uninterruptible power supply. When calibrating the screening instruments at different positions, the blackbody radiation source is prevented from being powered off due to position movement, and the waiting time required for the blackbody radiation source to restart and stabilize is avoided, thereby improving the efficiency of on-site calibration. The device of the present invention is placed on a mobile cart, which is convenient for on-site calibration and movement, and reduces the labor intensity of the calibration personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 is a front view schematic diagram of the bionic human head of the present invention;

[0021] Figure 3It is a cross-sectional schematic diagram of the bionic human head in the present invention.

[0022] In the figure: 1. Mobile cart; 2. Uninterruptible power supply; 3. Lifting platform; 4. Hand wheel; 5. Tilting platform; 6. Support arm; 7. Bionic head; 8. Black body radiation source; 9. Black body cavity; 10. First heating coil; 11. Second heating coil; 12. Insulation cotton; 13. First thermometer; 14. First power cord; 15. Second thermometer; 16. Second power cord; 17. First extension cord; 18. Second extension cord; 19. First thermostat; 20. Second thermostat; 21. Positioning nut. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention;

[0024] Reference Figure 1-3 A bionic device for mobile calibration of a thermal imaging screening instrument comprises a mobile cart 1 and a bionic human head 7. The size of the bionic human head 7 is in a ratio of 1:1 to that of an adult human head. The bionic human head 7 has a built-in blackbody radiation source 8 with an effective emissivity of 0.98. A blackbody cavity 9 of the blackbody radiation source 8 is located at the center of the forehead of the bionic human head 7. A first heating coil 10 and a second heating coil 11 are wound around the outer side of the blackbody cavity 9. The first heating coil 10 and the second heating coil 11 are made of nickel-chromium wire inside and glass fiber outside. The first heating coil 10 is close to the opening of the blackbody cavity 9 and covers 1 / 3 of the outer wall of the blackbody cavity 9. The second heating coil 11 is far away from the opening of the blackbody cavity 9 and covers 2 / 3 of the outer wall of the blackbody cavity 9. The outer side of the first heating coil 10 and the second heating coil 11 is filled with thermal insulation cotton 12. The inner wall of the blackbody cavity 9 is buried with a heat preservation cotton 12. A first thermometer 13 and a second thermometer 15, wherein the temperature sensing point of the first thermometer 13 is close to the opening of the black body cavity 9, and the temperature sensing point of the second thermometer 15 is far from the opening of the black body cavity 9, the first heating coil 10 is connected to a first power line 14, and the second heating coil 11 is connected to a second power line 16, the first power line 14 is connected to the output end of a first temperature controller 19, and the second power line 16 is connected to the output end of a second temperature controller 20, the first thermometer 13 is connected to the input end of the first temperature controller 19 through a first extension line 17, and the second thermometer 15 is connected to the input end of the second temperature controller 20 through a second extension line 18, the first temperature controller 19 and the second temperature controller 20 are powered by a power bus, and the power bus is connected to the 220V AC output of an uninterruptible power supply 2, and a positioning nut 21 is provided on the bottom surface of the bionic head 7.

[0025] A lifting platform 3 is arranged on the mobile cart 1, and a hand wheel 4 is arranged on the lifting platform 3. An uninterruptible power supply 2 is placed below the lifting platform 3. A tilting platform 5 and a support arm 6 are rotatably arranged above the lifting platform 3. A card slot is provided on the bottom wall of the tilting platform 5 near one end of the support arm 6, and the card slot matches the end of the support arm 6. The tilting platform 5 is supported by the support arm 6. The bionic human head 7 is placed on the tilting platform 5. The input end of the uninterruptible power supply 2 is connected to the mains through a power cord, and the input end of the black body radiation source 8 is connected to the output end of the uninterruptible power supply 2 through a power cord.

[0026] The combination of the first heating coil 10, the first thermometer 13, the first extension line 17, the first temperature controller 19, and the combination of the second heating coil 11, the second thermometer 15, the second extension line 18, and the second temperature controller 20 forms a dual-stage independent temperature control capability of the black body radiation source 8, effectively avoiding the phenomenon of low temperature in the opening section of the black body cavity 9 due to convection heat dissipation of the external air, effectively ensuring the temperature uniformity of the black body cavity 9, and ensuring the stability of the brightness temperature of the black body radiation source 8. After the two-stage temperature is stable and equal, it can be used for the calibration of the screening instrument.

[0027] In this embodiment, preferably, the temperature range of the blackbody radiation source 8 is room temperature + 5°C - 40.0°C, which is equal to the surface emissivity of an adult's forehead, and the first thermometer 13 and the second thermometer 15 are Pt100. The brightness temperature of the blackbody radiation source 8 should be traced back to the social public measurement standard every year, and the effective emissivity of the blackbody radiation source 8 should be measured at least once every 3 years. In this embodiment, after calibration, the brightness temperature of the blackbody radiation source 8 is 0.1°C lower than the display temperature of the thermostat, that is, its correction value is -0.1°C.

[0028] In this embodiment, preferably, the black body cavity 9 is made of red copper segments, the inner wall is coated with black paint with an emissivity of not less than 0.9, the aspect ratio of the cylindrical segment of the black body cavity 9 is not less than 2, and the bottom of the black body cavity 9 is a non-flat cone surface or anisotropic surface.

[0029] In this embodiment, preferably, the stroke of the lifting platform 3 is adjusted to 0-45 cm by the hand wheel 4, the tilting angle range of the tilting platform 5 is 0-60°, and the tilting platform 5 is a non-slip surface. The lifting platform 3 and the tilting platform 5 can enable the bionic head 7 to move up and down and tilt, so that the axis of the black body cavity 9 is perpendicular to the receiving surface of the screening instrument, reducing the measurement uncertainty. The lifting platform 3 is supported by a fixed partition, and the uninterruptible power supply 2 is located below the fixed partition.

[0030] In this embodiment, preferably, the bionic human head 7 can be fixed on the tripod by the positioning nut 21, and when used alone, the tripod can enable the bionic human head 7 to move up and down and tilt.

[0031] In this embodiment, the bionic human head 7 is first fixed on the tilting platform 5, the input end of the uninterruptible power supply 2 is connected to the mains, the temperature of the black body radiation source 8 is set to 37.4°C, the distance between the bottom of the black body cavity 9 and the receiving surface of the screening instrument is the screening instrument measurement distance (3m) set by the computer software, the lifting platform 3 and the tilting platform 5 are adjusted to make the axis of the black body cavity 9 perpendicular to the receiving surface of the screening instrument, and the imaging area of ​​the black body cavity 9 on the computer software reaches the minimum; after the first temperature controller 19 and the second temperature controller 20 both reach 37.4°C and stabilize for 10 minutes, the temperature of the black body cavity 9 measured by the screening instrument is read on the computer software as 37.1°C. The error of the calibrated screening instrument in the body temperature mode is calculated by the following formula:

[0032] Error = computer software reading - (temperature controller display value + correction value)

[0033] =37.1–(37.4–0.1)=-0.2℃

[0034] That is, the error of the calibrated screening instrument in the body temperature mode is -0.2°C (the calibration temperature point is 37.3°C).

[0035] After calibrating the screening instrument, disconnect the uninterruptible power supply 2 from the mains; the uninterruptible power supply 2 supplies power to the blackbody radiation source 8 through the inverter via its own battery to maintain the temperature of the blackbody radiation source 8 stable; when reaching the calibration location of the next screening instrument, connect the uninterruptible power supply 2 to the mains.

Claims

1. A bionic device for mobile calibration of a thermal imaging screening instrument, comprising a mobile cart (1) and a bionic human head (7), characterized in that: The bionic human head (7) has a built-in blackbody radiation source (8) with an effective emissivity of 0.

98. The blackbody cavity (9) of the blackbody radiation source (8) is located at the center of the forehead of the bionic human head (7). A first heating coil (10) and a second heating coil (11) are wound around the outside of the blackbody cavity (9). The first heating coil (10) is close to the opening of the blackbody cavity (9) and covers 1 / 3 of the outer wall of the blackbody cavity (9). The second heating coil (11) is far from the opening of the blackbody cavity (9) and covers 2 / 3 of the outer wall of the blackbody cavity (9). The outside of the first heating coil (10) and the second heating coil (11) are filled with thermal insulation cotton (12). The inner wall of the blackbody cavity (9) is embedded with a first thermometer (13) and a second thermometer (15). The temperature sensing point of the thermometer (13) is close to the opening of the black body cavity (9), and the temperature sensing point of the second thermometer (15) is far from the opening of the black body cavity (9); the first heating coil (10) is connected to a first power line (14), and the second heating coil (11) is connected to a second power line (16); the first power line (14) is connected to an output end of a first temperature controller (19), and the second power line (16) is connected to an output end of a second temperature controller (20); the first thermometer (13) is connected to an input end of the first temperature controller (19) via a first extension line (17), and the second thermometer (15) is connected to an input end of the second temperature controller (20) via a second extension line (18); and a positioning nut (21) is provided on the bottom surface of the bionic head (7); The mobile cart (1) is provided with a lifting platform (3), the lifting platform (3) is provided with a hand wheel (4), an uninterruptible power supply (2) is placed below the lifting platform (3), a tilting platform (5) and a support arm (6) are rotatably arranged above the lifting platform (3), a bottom wall of the tilting platform (5) close to one end of the support arm (6) is provided with a card slot, the card slot matches the end of the support arm (6), the tilting platform (5) is supported by the support arm (6), the bionic head (7) is placed on the tilting platform (5), the input end of the uninterruptible power supply (2) is connected to the mains via a power line, the first temperature controller (19) and the second temperature controller (20) of the black body radiation source (8) are powered by a power bus, and the power bus is connected to the 220V alternating current output by the uninterruptible power supply (2).

2. A bionic device for mobile calibration of a thermal imaging screening instrument according to claim 1, characterized in that: The temperature range of the black body radiation source (8) is room temperature + 5°C - 40.0°C, and the first thermometer (13) and the second thermometer (15) are of model Pt100.

3. The bionic device for mobile calibration of thermal imaging screening instrument according to claim 1, characterized in that: The black body cavity (9) is made of red copper segments, the inner wall of which is coated with black paint having an emissivity of not less than 0.9, the aspect ratio of the cylindrical segment of the black body cavity (9) is not less than 2, and the bottom of the black body cavity (9) is a non-flat cone or anisotropic surface.

4. The bionic device for mobile calibration of thermal imaging screening instrument according to claim 1, characterized in that: The travel of the lifting platform (3) is adjusted to 0-45 cm by a hand wheel (4), the tilting angle range of the tilting platform (5) is 0-60°, the lifting platform (3) is supported by a fixed partition, and the uninterruptible power supply (2) is located below the fixed partition.

5. The bionic device for mobile calibration of thermal imaging screening instrument according to claim 1, characterized in that: The bionic human head (7) can be fixed on a tripod via the positioning nut (21) and can be used alone.

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