Flue-cured tobacco leaf quality evaluation device based on machine vision and near infrared

Abstract

The utility model discloses a flue-cured tobacco leaf quality evaluation device based on machine vision and near infrared rays, which shoots tobacco leaves by introducing machine vision and intuitively evaluates image characteristics of the tobacco leaves so as to realize rapid and accurate measurement on indexes such as maturity, damage, color, oil content, leaf area and the like of the tobacco leaves. Meanwhile, the content of main inherent chemical components of the tobacco leaves is measured by introducing near infrared spectrum measurement, and meanwhile, the thickness, tensile force and elasticity analysis of the tobacco leaves and a matched cutting measurement device are also introduced, so that the quality indexes of the tobacco leaves are perfected, and the accuracy of quality judgment is improved.

Description

Technical Field

[0001] This utility model relates to the field of tobacco leaf evaluation, specifically a device for evaluating the quality of flue-cured tobacco leaves based on machine vision and near-infrared spectroscopy. Background Technology

[0002] The quality of tobacco raw materials has a crucial impact on the production of tobacco products. During tobacco leaf procurement, leaves are typically graded based on appearance and other quality factors. Different grades have different prices and varying industrial usability. Higher-grade tobacco leaves, in addition to superior appearance and physical quality, generally have a more harmonious chemical composition and better sensory evaluation. Furthermore, the leaf blend of a single brand of cigarettes often consists of tobacco leaves from multiple origins and of different grades. When one type of raw material is scarce, leaves of similar quality are used as substitutes. Currently, production largely relies on manual grading, primarily through visual observation and experience-based judgment. This method is time-consuming, labor-intensive, and highly susceptible to subjective influences. Devices proposed in the field of tobacco leaf grading research mostly involve single-function machine vision for feature and color assessment, with limited involvement in physical quality and chemical composition detection. Devices that measure multiple indicators for quality evaluation are rarely seen in frontline production.

[0003] Therefore, exploring and improving evaluation devices and systems for tobacco leaf quality grades will help enhance the availability and substitutability of raw materials in the industry, thereby improving the quality of cigarette products and the stability of leaf blend formulations. Utility Model Content

[0004] To address the aforementioned problems, this invention provides a device for evaluating the quality of flue-cured tobacco leaves based on machine vision and near-infrared spectroscopy.

[0005] The technical solution adopted by this utility model to solve its technical problem is as follows:

[0006] A quality evaluation device for flue-cured tobacco leaves based on machine vision and near-infrared spectroscopy, including

[0007] Main structure and its components

[0008] The tobacco leaf transport area includes a tobacco leaf conveyor belt, on one side of which a label holder is installed. The label holder is equipped with a moving track, within which a main vein fixing clamp and a label codec are installed. The main vein fixing clamp can move horizontally within the moving track, and the label codec can move both horizontally and vertically within the moving track. A physical appearance area robotic arm and a chemical composition area robotic arm are respectively installed at the middle and lower reaches of the tobacco leaf conveyor belt.

[0009] The appearance and physical measurement area includes a camera table, on one side of which an industrial camera is installed and on the other side a cutting blade moving track. The cutting blade moving track has two independent transmission chains, which are respectively connected to a tobacco strip cutting blade and a tobacco circular punching blade. The appearance and physical measurement area is also equipped with a tobacco thickness measuring device and a tobacco strip tension measuring device.

[0010] The chemical composition measurement area includes a tobacco leaf placement platform. Two moving tracks are installed parallel to each other on both sides of the tobacco leaf placement platform. A metal rod spans between the moving tracks and a bridge-shaped moving track is built in. The three moving tracks together form a near-infrared moving track. A near-infrared emitter is installed in the bridge-shaped moving track. A near-infrared device is installed in the empty area of ​​the chemical composition measurement area as an analysis device for information on different wavelengths of reflected light.

[0011] The grading area includes a grading area moving track, which is perpendicular to the tobacco leaf conveyor belt. A grading area robotic arm is installed in the grading area moving track, and its range of motion covers the entire grading area. Several grading boxes are set on one side of the grading area moving track, and a tobacco leaf storage box is installed next to each grading box for storing tobacco leaves after grading in a single batch.

[0012] Furthermore, the tobacco leaf conveyor belt structure is a roller conveyor belt made of leather.

[0013] Furthermore, the label holder structure is a raised column shape.

[0014] Furthermore, the main vein fixing clamp structure is a mechanical gripper to clamp the tobacco stem from the side, and the tag codec has built-in NFC and an electromagnet for data import and tag encoding / decoding switching.

[0015] Furthermore, the robotic arm in the appearance and physical measurement area has the same structure as the robotic arm in the chemical composition area. Both have a rotating base connected to the top of the main structure, which can drive the robotic arm to rotate. A multi-joint movable arm is installed on the rotating base, and a mechanical gripper is installed on the top of the movable arm. Its range of motion covers the adjacent section of the tobacco conveyor belt, as well as the entire position of the appearance and physical measurement area and the chemical composition measurement area, respectively.

[0016] Furthermore, fixed baffles are installed on the sides and downstream end of the tobacco conveyor belt to prevent the device from being damaged by impact and to prevent tobacco powder from falling into the device.

[0017] Furthermore, a label placement box is installed on one side of the robotic arm in the physical area of ​​the exterior. The box is a rectangular box with a missing top surface and is used for label placement and storage.

[0018] Furthermore, the appearance and physical measurement area is located upstream of the tobacco transport area.

[0019] Furthermore, the photographic platform structure is a rectangular frustum protrusion made of frosted material.

[0020] Furthermore, the industrial camera has an inverted "L" shape, with a vertically downward-facing camera mounted at the top end, and its imaging range covers the entire top of the camera table.

[0021] Furthermore, the tobacco leaf strip cutting blade is a circular roller with a certain spacing, all mounted on the same roller shaft, which is connected to a horizontal telescopic rod. The horizontal telescopic rod is mounted on a movable base, which is connected inside the cutting blade moving track. The tobacco leaf circular punching blade is a ring-shaped twisting blade, mounted on the horizontal telescopic rod, which is mounted on the movable base, which is also connected inside the cutting blade moving track.

[0022] Furthermore, the tobacco leaf thickness measuring device includes a cylindrical base, a measuring rod installed on one side of the cylindrical base, and a downward-facing, adjustable-pressure hydraulic column at the top of the measuring rod, which is directly opposite the center of the cylindrical base and can record the moving distance during the extension and retraction process; the tobacco stick tension measuring device has a raised truncated pyramid structure, a moving track installed on one side of the truncated pyramid, and two identical mechanical grippers installed in the moving track, which can open and close along the track, and have force measuring and distance measuring functions.

[0023] Furthermore, the chemical composition measurement area is located downstream of the tobacco leaf transport area.

[0024] Furthermore, the near-infrared transmitter is a probe consisting of a near-infrared transmitter and a receiver, with a vertical lifting rod at the top connected to a bridge-shaped moving track, which can drive the near-infrared transmitter to move up and down in the vertical direction.

[0025] Furthermore, the grading zone is located at the end of the tobacco transport zone.

[0026] Furthermore, the grading boxes are semi-enclosed boxes arranged adjacent to each other, and the tobacco storage boxes are rectangular boxes without a top surface.

[0027] The beneficial effects of this utility model are as follows:

[0028] This invention introduces machine vision to photograph tobacco leaves, enabling intuitive evaluation of their image characteristics. This allows for rapid and accurate measurement of indicators such as maturity, damage, color, oil content, and leaf area. Furthermore, by incorporating near-infrared spectroscopy, the invention determines the content of the main internal chemical components of the tobacco leaves. Additionally, it includes analysis of tobacco leaf thickness, tensile strength, and elasticity, along with a corresponding cutting and measuring device, to improve the quality indicators of the tobacco leaves and enhance the accuracy of quality assessment. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0030] Figure 1 This is a top view of the structure of a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared spectroscopy according to this utility model.

[0031] Figure 2 This is an isometric view of the structure of a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared spectroscopy according to this utility model.

[0032] Figure 3 This is an isometric view of the appearance and physical measurement area of ​​a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared spectroscopy according to this utility model.

[0033] Figure 4 This is an isometric view of the chemical composition measurement area of ​​a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared spectroscopy, according to this utility model.

[0034] Figure 5 This is a schematic diagram of the near-infrared emitter probe in the chemical composition measurement area of ​​a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared technology, according to this utility model. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] This embodiment relates to a device for evaluating the quality of flue-cured tobacco leaves based on machine vision and near-infrared spectroscopy, in order to determine various quality indicators of tobacco leaves, referring to... Figures 1-5 The evaluation device includes:

[0037] The structure comprises: 1. Tobacco leaf transportation area; 2. Appearance and physical measurement area; 3. Chemical composition measurement area; 4. Grading area; and 5. Main structure. The main structure 5 is divided into a platform 51 and a control panel 52. The platform 51 is a box-shaped structure, with all other functional components mounted on its top surface. A built-in computer connects to each component and the control panel 52. The control panel 52 is a touch-screen monitor with a data interface for data transmission, serving as an interactive platform between the device and the operator.

[0038] The tobacco leaf transport area 1 includes a tobacco leaf conveyor belt 11, which is a roller conveyor belt made of leather. A label holder 12 is installed on one side of the belt; this label holder is a raised cylindrical structure with a moving track. A main vein fixing clip 13 and a label encoder / decoder 14 are installed within the track. The main vein fixing clip 13 can move horizontally within the moving track, and the label encoder / decoder 14 can move both horizontally and vertically to avoid interference from the tobacco stems during label handover. The main vein fixing clip 13 is a mechanical gripper with a 90° horizontal bend to hold the tobacco stem from the side. The label encoder / decoder 14 is a standard mechanical gripper design, incorporating NFC and an electromagnet for data import and label encoding / decoding switching.

[0039] Two robotic arms are installed at the midstream and downstream ends of the tobacco conveyor belt 11: one for the appearance and physical measurement area (15) and the other for the chemical composition area (16). These two arms are identical except for their installation positions. Each arm has a rotating base connected to the top of the device platform 51, allowing it to rotate. A multi-jointed movable arm is mounted on the rotating base, and a mechanical gripper is installed at the top of the movable arm. The range of motion covers adjacent sections of the tobacco conveyor belt 11, as well as the entire area of ​​the appearance and physical measurement area 2 and the chemical composition measurement area 3, respectively. Fixed baffles 17 are installed on the side and downstream end of the tobacco conveyor belt 11 to prevent damage from collisions between the moving parts and to prevent tobacco powder from falling into the device. A label placement box 18, a rectangular box missing its top surface, is installed on one side of the appearance and physical measurement area robotic arm 15 for label storage.

[0040] The appearance and physical measurement area 2 is located upstream of the tobacco transport area 1 and includes a camera platform 21 with a rectangular truncated pyramid structure and a matte, cut-resistant frosted finish. An industrial camera 22 with an inverted "L" shape is installed on one side of the camera platform 21, with a vertically downward-facing camera at the top end, covering the entire top of the camera platform 21. A cutting blade moving track 23 is installed on the other side of the camera platform 21, powered by a stepper motor. The track has two independent transmission chains for transmission, which are respectively connected to the tobacco strip cutting blade 24 and the tobacco circular punching blade 25. The main structure of the tobacco strip cutting blade 24 is a circular roller with a certain spacing, all mounted on the same roller shaft. The roller shaft is connected to a horizontal telescopic rod, which is mounted on a movable base. The movable base is connected inside the cutting blade moving track 23. The main structure of the tobacco circular punching blade 25 is a ring-shaped torsion blade, mounted on a horizontal telescopic rod, which is mounted on a movable base. The movable base is also connected inside the cutting blade moving track 23.

[0041] In the empty area of ​​the appearance and physical measurement area 2, a tobacco leaf thickness measuring device 26 is installed. The device has a cylindrical base with a measuring rod installed on one side. The top of the measuring rod has a downward-facing, adjustable hydraulic column with its axis aligned with the center of the cylindrical base. The device can record the movement distance during extension and retraction. In addition, a tobacco strip tension measuring device 27 is installed. The device has a raised truncated pyramid structure with a moving track installed on one side. Two identical mechanical grippers are installed in the moving track. The grippers can open and close along the track and have force and distance measurement functions.

[0042] The chemical composition measurement area 3 is located downstream of the tobacco transport area 1 and includes a tobacco leaf placement platform 31. The platform is a raised rectangular truncated pyramid with two parallel moving tracks on either side. A metal rod spans between the tracks, housing a bridge-shaped moving track perpendicular to the two aforementioned tracks. These three tracks together form a near-infrared moving track 32. A near-infrared emitter 33 is installed within the bridge-shaped moving track, allowing for precise horizontal movement along the track. The near-infrared emitter 33 is a probe composed of a near-infrared emitter and a receiver, with a vertical lifting rod at the top connected to the track, enabling vertical movement of the near-infrared emitter 33. An infrared device 34 is installed in the empty area of ​​the chemical composition measurement area 3 as a device for analyzing information from different wavelengths of reflected light.

[0043] The grading zone 4 is located at the end of the tobacco transport zone 1 and has a grading area moving track 41, perpendicular to the tobacco conveyor belt 11. A grading area robotic arm 42 is installed within the grading area moving track 41, and has a moving base. The structure above the base is the same as other robotic arms, and its range of motion covers the entire grading zone 4. A grading box 43 is installed on one side of the grading area moving track 41. The box is a semi-enclosed box, and multiple boxes are arranged adjacent to each other. Next to each box is a tobacco leaf storage box 44, which is a rectangular box without a top surface, used for storing tobacco leaves after grading in a single batch.

[0044] In use, this device first places the tobacco leaves in the appearance and physical measurement area 2 via the tobacco leaf conveyor belt 11. An industrial camera 22 captures images of the tobacco leaves so that external equipment can evaluate the features of the tobacco leaf images. This allows for rapid and accurate measurement of indicators such as maturity, damage, color, oil content, and leaf area of ​​the tobacco leaves. At the same time, physical indicators such as thickness and tensile strength of the tobacco leaves are measured. Then, the tobacco leaves are moved to the chemical composition measurement area 3, where near-infrared light is emitted at different points on the tobacco leaves. The main chemical components of the tobacco leaves are measured by the near-infrared device 34. Finally, based on the scores of various indicators (appearance, physical, and chemical) of the tobacco leaves, the grade and industrial usability evaluation of the tobacco leaves are obtained through weighted calculation.

[0045] Specifically, turn on the power to the device at control panel 52, selectively set the tobacco leaf indicators to be collected this time, and start the device operation.

[0046] The tobacco leaves move along the tobacco leaf conveyor belt 11 to the label holder 12. The main vein fixing clamp 13 clamps the base of the main vein of the tobacco leaf to fix it. The appearance physical area robotic arm 15 picks up a label from the label placement box 18 and transfers it to the label encoder 14. The label encoder 14 fixes the label to the base of the tobacco leaf and prints the serial number. After the label is fixed, the main vein fixing clamp 13 releases to let the tobacco leaf fall off.

[0047] The tobacco leaves continue to move along the tobacco leaf conveyor belt 11. The appearance physical area robotic arm 15 moves the tobacco leaves in the stacking order to the top center of the camera table 21 and lays the tobacco leaves flat. The industrial camera 22 captures the images of the tobacco leaves and transmits them to an external computer to visually measure the image characteristics and various appearance indicators of the tobacco leaves.

[0048] If the physical index measurement is activated, the tobacco strip cutting knife 24 and the tobacco circular punching knife 25 are moved along the cutting knife moving track 23 to the position of the tobacco leaf, and the cutting knife is extended and retracted to the surface of the tobacco leaf to cut the tobacco leaf into tobacco strips of a fixed width and several tobacco sheets of the same diameter. The cut tobacco strips are placed at the position of the tobacco strip tension measuring device 27 by the mechanical arm 15 in the appearance physical area. The two fixed clamps of the tobacco strip tension measuring device 27 clamp the two sides of the tobacco strip respectively. With the assistance of the mechanical arm, the tobacco strip is slightly straightened. Then the two fixed clamps are extended to the sides until the tobacco strip breaks. The elongation and tension data of the tobacco strip at this time are recorded.

[0049] The cut tobacco sheet is placed at the position of the tobacco sheet thickness measuring device 26 by the robotic arm 15 in the physical area of ​​the appearance. The hydraulic telescopic rod of the tobacco sheet thickness measuring device 26 descends to contact the tobacco leaf and records the tobacco sheet thickness at this time. The telescopic rod continues to increase the pressure and records the change in tobacco sheet thickness with the pressure.

[0050] After the tobacco sticks and leaves are measured, the robotic arm 15 in the physical appearance area cleans the measured samples and moves the tobacco leaves to the tobacco leaf conveyor belt. The tobacco leaves move with the tobacco leaf conveyor belt to the chemical composition measurement area 3. The robotic arm 16 in the chemical composition area moves the tobacco leaves to the top of the tobacco leaf placement platform 31. The near-infrared emitter 33 moves along its moving track 32 to the measurement points on both sides of the midrib, the leaf tip, the leaf base, and both sides of the leaf edge. After reaching the corresponding point, the near-infrared emitter 33 descends under the action of the lifting rod, contacts the surface of the tobacco leaf, and then emits near-infrared rays into the tobacco leaf through the near-infrared emitting module and receives the reflected rays through the near-infrared receiving module. The received data is transmitted to the near-infrared device 34, and then rises along the lifting rod to move to the next point. The robotic arm 16 in the chemical composition area moves the tobacco leaves back to the tobacco leaf conveyor belt 11. The near-infrared device 34 reads the reflected rays of different wavelengths to obtain the content of the main chemical components of the tobacco leaves. Finally, the grade and industrial usability evaluation of the tobacco leaves are obtained through weighted calculation.

[0051] It should be noted that this utility model aims to protect a flue-cured tobacco leaf quality evaluation device based on machine vision and near-infrared technology. The image processing algorithm involved is not within the scope of protection of this utility model. This device can use existing image processing algorithms to measure appearance indicators such as maturity, damage and leaf area of ​​tobacco leaves.

[0052] It should also be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A device for evaluating the quality of flue-cured tobacco leaves based on machine vision and near-infrared, characterized in that it comprises: The main body structure and the structure arranged thereon The tobacco conveying area comprises a tobacco conveying belt, one side of which is provided with a label fixing device, the label fixing device is provided with a moving track, a main vein fixing clamp and a label encoder are arranged in the moving track, the main vein fixing clamp can move horizontally in the moving track, the label encoder can move horizontally and vertically in the moving track, and an appearance and physical measurement area mechanical arm and a chemical component area mechanical arm are respectively arranged at the middle and downstream of the tobacco conveying belt; The appearance and physical measurement area comprises a photographing table, one side of the photographing table is provided with an industrial camera, and the other side is provided with a cutter moving track, a tobacco strip-shaped cutter and a tobacco circular punching cutter are arranged in the cutter moving track, the appearance and physical measurement area is further provided with a tobacco thickness measurer and a tobacco strip tensile force measurer; The chemical component measurement area comprises a tobacco placing table, two moving tracks are arranged in parallel on two sides of the tobacco placing table, a metal rod body is arranged across the moving tracks, and a bridge-shaped moving track is arranged in the metal rod body, the three moving tracks jointly form a near-infrared moving track, a near-infrared emitter is arranged in the bridge-shaped moving track, and a near-infrared device is arranged in the empty area of the chemical component measurement area, as a reflection light different waveband information analysis device; The grade division area comprises a grading area moving track, the direction of the grading area moving track is perpendicular to the tobacco conveying belt, a grading area mechanical arm is arranged in the grading area moving track, and a plurality of grade division boxes are arranged on one side of the grading area moving track, and a tobacco storage box is arranged beside each grade division box.

2. The tobacco quality evaluation device according to claim 1, wherein the main vein fixing clamp structure is a mechanical gripper to clamp the tobacco stem from the side, and the label encoder is provided with an NFC and an electromagnet as data import and label encoding switch.

3. The tobacco quality evaluation device according to claim 1, wherein the appearance and physical measurement area mechanical arm and the chemical component area mechanical arm have the same structure, and each has a rotating base connected to the top of the main body structure to drive the mechanical arm to rotate, a multi-joint movable arm is arranged on the rotating base, and a mechanical gripper is arranged at the top of the movable arm, the movable range of the mechanical gripper covers adjacent sections of the tobacco conveying belt, and covers all positions of the appearance and physical measurement area and the chemical component measurement area.

4. The tobacco quality evaluation device according to claim 1, wherein the tobacco strip-shaped cutter is a circular hob with a certain spacing, and is arranged on the same hob shaft, the hob shaft is connected to a horizontal telescopic rod, the horizontal telescopic rod is arranged on a movable base, and the movable base is connected to the inside of the cutter moving track; and the tobacco circular punching cutter is a circular ring type twist cutter, and is arranged on a horizontal telescopic rod, the horizontal telescopic rod is arranged on a movable base, and the movable base is also connected to the inside of the cutter moving track.

5. The tobacco quality evaluation device according to claim 1, wherein ​ ​ ​ The tobacco leaf thickness measurer includes a cylindrical base, one side of which is provided with a measuring rod, the top end of which is provided with a downwardly directed hydraulic column with adjustable pressure, which is opposite the center of the cylindrical base and can record the moving distance during extension and retraction; the tobacco strip tensile force measurer has a convex prism structure, one side of which is provided with a moving track, and two mechanically identical clamping hands are installed in the moving track and can perform opening and closing movements along the track, with force and distance measuring functions.

6. The tobacco quality evaluation device according to claim 1, characterized in that: The near-infrared emitter is a probe composed of a near-infrared emitter and a receiver, which has a vertical lifting rod at the top and is connected to a bridge-shaped moving track, so as to drive the near-infrared emitter to perform lifting movement in the vertical direction.

7. The tobacco quality evaluation device according to claim 1, characterized in that: The side edges and the downstream end of the tobacco conveying belt are provided with fixed baffles to prevent damage to the device and the falling of tobacco powder into the device.

8. The tobacco quality evaluation device according to claim 1, characterized in that: One side of the mechanical arm of the appearance and physical area is provided with a label placing box, which has the structure of a rectangular box with a missing top and is used as a label placing and storage.

9. The tobacco quality evaluation device according to claim 1, characterized in that: The industrial camera has an inverted "L" shape, and a vertically downwardly directed camera is installed at the top end, which covers the entire top of the camera table.

10. The tobacco quality evaluation device according to claim 1, characterized in that: The grade division box is a semi-enclosed box body arranged adjacently, and the tobacco storage box is a rectangular box body with a missing top.

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