OCT real-time detection method and system for drug coating thickness suitable for assembly line

Abstract

The present invention relates to the technical field of drug production quality inspection, and specifically discloses an OCT real-time inspection method and system for drug coating thickness suitable for an assembly line, the method comprising: obtaining tablets from a drug production line and placing them on an inspection assembly line; the tablets move on the inspection assembly line, a machine vision system captures an image containing tablets, identifies the tablets from the image, calculates the inspection position, inspection length, placement angle, horizontal distance and vertical distance of the tablets; generates OCT system working parameters; controls the scanning galvanometer of the OCT system to move, and scans the tablets to obtain an OCT image of the tablets; and calculates the coating thickness of the tablets according to the OCT image of the tablets. The present invention can identify tablets of different shapes and detect the coating thickness of the drug in real time online without stopping the movement of the drug.

Description

Technical Field

[0001] The present invention relates to the technical field of drug production quality detection, and in particular to an OCT real-time detection method and system for drug coating thickness suitable for an assembly line. Background Art

[0002] In the process of drug production, the coating thickness of drugs is one of the important factors affecting the quality and efficacy of drugs. Traditional coating thickness detection methods include offline detection and destructive detection. For example, the Chinese invention patent with application publication number CN111504977A discloses a method and system for measuring the thickness of each component layer of micropills. The micropill raw materials and excipients are placed on a glass slide for sample preparation; the laser wavelength, power and other conditions are selected to perform Raman scanning on the glass slide carrying the sample to obtain the Raman characteristic spectrum of the raw and excipients; the micropills are cut with a blade and the cross section of the micropills is Raman scanned; the Raman characteristic spectrum of the raw and excipients is imported into the surface scanning data and analyzed, and different components are calibrated with different colors to form a surface scanning component distribution image, and the thickness of each component layer is marked on the Raman component imaging map with a ruler. This invention patent can realize offline detection of drug coating thickness. However, this type of method usually requires stopping the movement of the drug during the production process, and the detection efficiency is low. Summary of the invention

[0003] The present invention aims to solve the problem that the drug coating thickness cannot be quickly detected in the drug production process and the detection efficiency is low. To this end, the present invention provides a drug coating thickness OCT real-time detection method and system suitable for assembly line, which has the advantages of strong adaptability, real-time online detection, high precision, non-destructive detection and high degree of automation, and can accurately detect the coating thickness online when the drug shape is irregular or diverse, without stopping the production process, improving production efficiency and detection consistency, thereby effectively improving the quality control level in the drug production process.

[0004] The present invention provides an OCT real-time detection method for drug coating thickness applicable to an assembly line, and the technical scheme adopted is as follows: comprising the following steps:

[0005] Step 1: Get the tablets from the drug production line and place them on the testing line;

[0006] Step 2: The tablet moves on the inspection line, and the machine vision system captures an image containing the tablet, identifies the tablet from the image, and calculates the inspection position, inspection length, placement angle, horizontal distance, and vertical distance of the tablet;

[0007] Step 3: Generate the OCT system working parameters according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet;

[0008] Step 4: controlling the movement of the scanning galvanometer of the OCT system according to the working parameters, and scanning the tablet to obtain an OCT image of the tablet;

[0009] Step 5: Calculate the coating thickness of the tablet according to the OCT image of the tablet.

[0010] Furthermore, in step 1, tablets are obtained from the drug production line multiple times, with one tablet being obtained from the drug production line each time.

[0011] Furthermore, in step 2, the process of calculating the detection position and detection length of the tablet is:

[0012] Determining the shape and size of the tablet identified in the image;

[0013] The detection position and detection length of the tablet are determined according to the shape and size of the tablet.

[0014] Furthermore, the detection position of an elliptical tablet is the straight line area between the two ends of the long axis of the medicine; the detection position of a circular tablet with no concave-convex texture on the surface is the area between the two ends of any diameter of the circular upper surface of the tablet; the detection position of a circular tablet with a concave-convex texture on the surface is the area between the two ends of a specific diameter direction of the circular upper surface of the tablet set according to the texture shape; the detection position of a triangular tablet is the area between the two ends of the straight line from the longest vertex on the triangular surface to the bottom edge; the detection position of a diamond tablet is the straight line area between the two farthest vertices on the diamond upper surface.

[0015] Furthermore, the placement angle is the angle between the detection position and the scanning direction of the OCT system.

[0016] Furthermore, the moving direction of the tablet is taken as the horizontal direction, and the scanning direction of the scanning galvanometer of the OCT system is taken as the vertical direction;

[0017] When the tablet is the first tablet, the horizontal distance of its position is the horizontal distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet, and the vertical distance of its position is the vertical distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet;

[0018] When the tablet is not the first tablet, the horizontal distance of its position is the horizontal distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet, and the vertical distance of its position is the vertical distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet.

[0019] Furthermore, in step 3, when the tablet identified in the image is the first tablet, the working parameters of the OCT system are calculated by formula (1):

[0020] (1)

[0021] in, represents the scanning speed of the OCT system for the first tablet, Indicates the forward speed of the tablet, Indicates the placement angle of the first tablet. Indicates the start time of the OCT system. Indicates the horizontal distance corresponding to the position of the first pill, Indicates the vertical distance corresponding to the position of the first tablet, Indicates the scanning time of the first tablet, Indicates the detection length of the first tablet;

[0022] When the tablet identified in the image is not the first tablet, the working parameters of the OCT system are calculated by formula (2):

[0023] (2)

[0024] in, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The duration of the starting point of the detection position of each pill, Indicates The end point of the detection position of the first tablet to the The horizontal distance between the starting points of the detection positions of the tablets, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The speed of the starting point of the detection position of each tablet, Indicates The end point of the detection position of the first tablet to the The vertical distance between the starting points of the detection positions of the tablets, Indicates the OCT system The scanning speed of each tablet, Indicates The angle of placement of pills, Indicates The scanning time of each pill, Indicates The detection length of each tablet, .

[0025] Furthermore, in step 4, an image processing algorithm is used to analyze the OCT image, determine the boundary of the coating layer of the tablet, measure the distance from the tablet surface to the inner boundary of the coating layer, and obtain the coating thickness of the tablet.

[0026] Furthermore, step 2 is specifically as follows:

[0027] The number of the machine vision systems is two, namely a first machine vision system and a second machine vision system.

[0028] The tablet moves on the inspection line and passes through the first machine vision system and the second machine vision system in sequence.

[0029] The first machine vision system captures a first image containing a tablet, identifies the tablet from the first image, and calculates a detection position and a detection length of the tablet;

[0030] The second machine vision system captures a second image containing the tablets, identifies the tablets from the second image, and calculates the placement angle, horizontal distance, and vertical distance of the tablets.

[0031] The present invention also provides an OCT real-time detection system for drug coating thickness applicable to an assembly line, which is used to execute the above-mentioned OCT real-time detection method for drug coating thickness applicable to an assembly line, comprising: a detection assembly line, and a tablet acquisition mechanism, a machine vision system and an OCT system sequentially arranged on the detection assembly line, wherein the machine vision system and the OCT system are both connected to a computer system;

[0032] The detection assembly line is used to move the tablets;

[0033] The tablet acquisition mechanism is used to acquire tablets from the drug production line and place them on the testing line;

[0034] The machine vision system is used to capture images containing tablets;

[0035] The computer system is used to identify the tablets from the image, calculate the detection position, detection length, placement angle, horizontal distance and vertical distance of the tablets; generate OCT system working parameters according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet; calculate the coating thickness of the tablets according to the OCT images of the tablets;

[0036] The OCT system is used to control the movement of its scanning galvanometer according to the working parameters and scan the tablet.

[0037] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0038] The present invention designs a detection position for each tablet, and uses a machine vision system to identify the tablet, calculate the detection position, detection length, placement angle, horizontal distance of the position and vertical distance of the position, determine the working parameters of the OCT system, control the movement of the scanning galvanometer, and accurately scan along the detection position of the tablet. The present invention can continuously obtain tablets from the drug production line and detect the tablet coating thickness in real time, thereby improving the detection efficiency.

[0039] The invention has the advantages of strong adaptability, real-time online detection, high precision, non-destructive detection and high degree of automation, and can identify tablets of different shapes and detect the coating thickness of the drug in real time online without stopping the movement of the drug.

[0040] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a flow chart provided by the present invention.

[0043] Figure 2 It is a schematic diagram of the system structure provided by the present invention.

[0044] Figure 3 This is the first tablet scanning schematic diagram provided by the present invention.

[0045] Figure 4 Schematic diagram of scanning the i-th tablet provided by the present invention.

[0046] Figure 5 This is a coating thickness detection diagram of the tablet provided by the present invention.

[0047] Reference numerals:

[0048] 1. Inspection line; 2. Tablet acquisition mechanism; 3. First machine vision system; 4. Second machine vision system; 5. OCT system; 6. Drug production line; 7. Tablets. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0050] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0051] Combine the following Figures 1 to 5 The present invention is further described in detail, and a real-time OCT detection method and system for drug coating thickness suitable for an assembly line are described as follows:

[0052] In this embodiment, Figure 1 As shown, a real-time OCT detection method for drug coating thickness suitable for an assembly line is provided, and the technical solution adopted is as follows: comprising the following steps:

[0053] Step 1: Get the tablets from the drug production line and place them on the testing line.

[0054] The tablets can be obtained by manual grabbing, tablet grabbing mechanism grabbing, etc. Generally, the drug production line is a tablet conveyor belt, and the tablet grabbing mechanism can be selected by mechanical gripping, negative pressure device adsorption. Figure 2 As shown, in this embodiment, a pneumatic manipulator obtains tablets from the tablet conveyor belt of the drug production line, obtains one tablet from the drug production line each time, and then places the tablet on the conveyor belt of the detection assembly line. The pneumatic manipulator continuously obtains tablets from the tablet conveyor belt, that is, the pneumatic manipulator periodically obtains tablets from the tablet conveyor belt and places them on the conveyor belt of the detection assembly line.

[0055] This embodiment obtains tablets from the drug production line for multiple times, and in subsequent steps, the tablet coating thickness is detected in real time, thereby improving the detection efficiency.

[0056] Since the number of tablets detected by the present embodiment is large, they are generally sent back to the tablet conveyor belt after detection. In order to facilitate the detection of tablets back to the tablet conveyor belt, the transmission belt of the detection line is arranged in parallel with the tablet conveyor belt.

[0057] Step 2: The tablet moves on the inspection assembly line, and the machine vision system captures an image containing the tablet, identifies the tablet from the image, and calculates the inspection position, inspection length, placement angle, horizontal distance, and vertical distance of the tablet.

[0058] In this step, one machine vision system or two machine vision systems can be used. When using one machine vision system, the detection position, detection length, placement angle, horizontal distance and vertical distance of the tablet are all calculated based on the image taken. When using two machine vision systems, the five parameters of the detection position, detection length, placement angle, horizontal distance and vertical distance of the tablet are divided into two parts and calculated by two images respectively. Compared with one machine vision system, the cost of two machine vision systems is higher, but the number of parameters that need to be calculated for each image is reduced, and the time required for calculation is also reduced, so that the second machine vision system can be closer to the OCT system, and the accuracy of the scanning results of the OCT system is slightly improved. It can also slightly increase the speed of the detection pipeline, that is, increase the forward speed of the tablet and slightly increase the detection speed.

[0059] The following uses two machine vision systems as examples to illustrate the specific working process of step 2:

[0060] The number of the machine vision systems is two, namely a first machine vision system and a second machine vision system.

[0061] The tablet moves on the inspection line and passes through the first machine vision system and the second machine vision system in sequence.

[0062] The first machine vision system captures a first image containing a tablet, identifies the tablet from the first image, and calculates a detection position and a detection length of the tablet;

[0063] The second machine vision system captures a second image containing the tablets, identifies the tablets from the second image, and calculates the placement angle, horizontal distance, and vertical distance of the tablets.

[0064] Machine vision systems are existing technologies and their main function is to identify pills from images.

[0065] The process of calculating the detection position and detection length of the tablet is:

[0066] Determining the shape and size of the tablet identified in the first image;

[0067] Determine the detection position and detection length corresponding to the tablet according to the shape and size of the tablet.

[0068] The calculation process of the detection position and the detection length is as follows: first, the detection position is determined according to the shape of the tablet, and then the detection length is calculated in combination with the detection position and the size of the tablet.

[0069] Tablets of different shapes have different detection positions. Common tablet shapes include elliptical tablets, circular tablets without concave-convex textures on the surface, circular tablets with concave-convex textures on the surface, triangular tablets, and diamond tablets. The corresponding detection positions are: the detection position of elliptical tablets is the straight line area between the two ends of the long axis of the drug; the detection position of circular tablets without concave-convex textures on the surface is the area between the two ends of any diameter on the circular upper surface of the tablet; the detection position of circular tablets with concave-convex textures on the surface is the area between the two ends of a specific diameter direction of the circular upper surface of the tablet set according to the texture shape; the detection position of triangular tablets is the area between the two ends of the straight line from the highest vertex of the triangle surface to the bottom edge; the detection position of diamond tablets is the straight line area between the two farthest vertices on the upper surface of the diamond.

[0070] For each tablet with different shapes and sizes, the corresponding detection position and detection length can be calculated in advance and stored in the database. According to the tablets identified in the first image, the corresponding detection position and detection length can be quickly obtained from the database to ensure detection efficiency.

[0071] like Figure 2-4 As shown, the shape of the tablet in this embodiment is elliptical, and the detection position is the straight line area between the two ends of the long axis direction of the medicine.

[0072] The placement angle corresponding to the tablet can be directly calculated based on the position of the tablet in the second image. The placement angle is the angle between the detection position and the starting scanning direction of the OCT system, such as Figure 3 As shown, the initial scanning direction is downward. The initial scanning direction is the positive direction of the moving direction of the scanning galvanometer of the OCT system.

[0073] The OCT scanning starting position of the scanning galvanometer of the OCT system is the edge of one side of the conveyor belt of the detection assembly line, and the scanning direction is perpendicular to the cross-sectional direction of the conveyor belt.

[0074] In this embodiment, the moving direction of the tablet is the horizontal direction, and the scanning direction of the scanning galvanometer of the OCT system is the vertical direction.

[0075] When the tablet is the first tablet, its horizontal distance is the horizontal distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet, and its vertical distance is the vertical distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet.

[0076] When the tablet is not the first tablet, the horizontal distance of its position is the horizontal distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet, and the vertical distance of its position is the vertical distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet.

[0077] Step 3: Generate the OCT system working parameters according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet.

[0078] When the tablet identified in the image is the first tablet, the working parameters of the OCT system are calculated using formula (1):

[0079] (1)

[0080] in, represents the scanning speed of the OCT system for the first tablet, Indicates the forward speed of the tablet, Indicates the placement angle of the first tablet. Indicates the start time of the OCT system. Indicates the horizontal distance corresponding to the position of the first pill, Indicates the vertical distance corresponding to the position of the first tablet, Indicates the scanning time of the first tablet, Indicates the detection length of the first tablet.

[0081] When the tablet identified in the image is not the first tablet, the working parameters of the OCT system are calculated by formula (2):

[0082] (2)

[0083] in, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The duration of the starting point of the detection position of each pill, Indicates The end point of the detection position of the first tablet to the The horizontal distance between the starting points of the detection positions of the tablets, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The speed of the starting point of the detection position of each tablet, Indicates The end point of the detection position of the first tablet to the The vertical distance between the starting points of the detection positions of the tablets, Indicates the OCT system The scanning speed of each tablet, Indicates The angle of placement of pills, Indicates The scanning time of each pill, Indicates The detection length of each tablet, .

[0084] Step 4: Control the movement of the scanning galvanometer of the OCT system according to the working parameters, and scan the tablet to obtain an OCT image of the tablet.

[0085] When the first tablet is taken, the working parameters include , and , the working process of the OCT system is:

[0086] like Figure 3 As shown, the first tablet is Move, pass After that, the scanning mirror of the OCT system starts from the starting position Scan, at this time the first pill is still When the scanning point of the scanning galvanometer intersects with the starting point of the detection position of the first tablet, the OCT system starts scanning the tablet. Move, scan the galvanometer to Move, pass , the scanning galvanometer moves to the end point of the detection position of the first tablet, and the OCT system finishes scanning the first tablet.

[0087] When it is not the first tablet, the working parameters include , , and , the working process of the OCT system is:

[0088] like Figure 4 As shown in the figure, the scanning galvanometer of the OCT system changes from The end point of the detection position of each tablet is Move, pass , reaching the The OCT system starts scanning at the starting point of the detection position of the first tablet. The distance that the pill moves horizontally to the right is , the distance that the scanning galvanometer moves upward in the vertical direction is . When scanning, The pills continue to Move, scan the galvanometer to Move, pass , the scanning galvanometer moves to the The end point of the detection position of the first tablet, at which time the OCT system The scanning of the tablets is completed. The OCT system scans the multiple tablets in sequence according to this process to obtain OCT images of the multiple tablets.

[0089] Step 5: Calculate the coating thickness of the tablet according to the OCT image of the tablet.

[0090] After the OCT system is started, it will emit a low-intensity beam and capture the internal structure of the tablet through interference; the OCT image will show multiple layers of the tablet, and the boundary between the coating layer and the tablet core is usually manifested in the image as different reflection signal intensities, such as Figure 5 As shown, the image processing algorithm is used to analyze the acquired OCT image, determine the boundary of the tablet coating layer, measure the distance from the tablet surface to the inner boundary of the coating layer, and obtain the coating thickness of the tablet. The OCT system analyzes the OCT image of each tablet and calculates the coating thickness of each tablet.

[0091] The present invention also provides a drug coating thickness OCT real-time detection system suitable for an assembly line, which is used to execute the above-mentioned drug coating thickness OCT real-time detection method suitable for an assembly line, such as Figure 2 As shown, it includes: a detection pipeline 1, and a tablet acquisition mechanism 2, a machine vision system and an OCT system 5 which are sequentially arranged on the detection pipeline 1, and the machine vision system and the OCT system 5 are both connected to a computer system.

[0092] The detection pipeline 1 is used to move the tablets 7;

[0093] The tablet acquisition mechanism 2 is used to acquire tablets 7 from the drug production line 6 and place them on the detection assembly line 1;

[0094] The machine vision system is used to capture images containing tablets;

[0095] The computer system is used to identify the tablet 7 from the image, calculate the detection position, detection length, placement angle, horizontal distance and vertical distance of the tablet 7; generate the working parameters of the OCT system 5 according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet 7; calculate the coating thickness of the tablet 7 according to the OCT image of the tablet 7;

[0096] The OCT system 5 is used to control the movement of its scanning galvanometer according to the working parameters and scan the tablet.

[0097] In another embodiment, the number of the machine vision systems is two, namely, a first machine vision system 3 and a second machine vision system 4. The first machine vision system 3 captures a first image containing a tablet, and the second machine vision system 4 captures a second image containing a tablet. At this time, the computer system identifies the tablet from the first image, calculates the detection position and detection length of the tablet; identifies the tablet from the second image, calculates the tablet's placement angle, horizontal distance, and vertical distance, and then generates the working parameters of the OCT system 5.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A real-time OCT detection method for drug coating thickness suitable for production line, characterized in that: The following steps are involved: Step 1: Get the tablets from the drug production line and place them on the testing line; Step 2: The tablet moves on the inspection line, and the machine vision system captures an image containing the tablet, identifies the tablet from the image, and calculates the inspection position, inspection length, placement angle, horizontal distance, and vertical distance of the tablet; The placement angle is the angle between the detection position and the scanning direction of the OCT system; The moving direction of the tablet is the horizontal direction, and the scanning direction of the scanning galvanometer of the OCT system is the vertical direction; When the tablet is the first tablet, the horizontal distance of its position is the horizontal distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet, and the vertical distance of its position is the vertical distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet; When the tablet is not the first tablet, the horizontal distance of its position is the horizontal distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet, and the vertical distance of its position is the vertical distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet; Step 3: Generate the OCT system working parameters according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet; In step 3, when the tablet identified in the image is the first tablet, the working parameters of the OCT system are calculated using formula (1): （1） in, represents the scanning speed of the OCT system for the first tablet, Indicates the forward speed of the tablet, Indicates the placement angle of the first tablet. Indicates the start time of the OCT system. Indicates the horizontal distance corresponding to the position of the first pill, Indicates the vertical distance corresponding to the position of the first tablet, Indicates the scanning time of the first tablet, Indicates the detection length of the first tablet; When the tablet identified in the image is not the first tablet, the working parameters of the OCT system are calculated by formula (2): （2） in, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The duration of the starting point of the detection position of each pill, Indicates The end point of the detection position of the first tablet to the The horizontal distance between the starting points of the detection positions of the tablets, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The speed of the starting point of the detection position of each tablet, Indicates The end point of the detection position of the first tablet to the The vertical distance between the starting points of the detection positions of the tablets, Indicates the OCT system Scanning speed of each tablet, Indicates The angle of placement of pills, Indicates The scanning time of each pill, Indicates The detection length of each tablet, ; Step 4: controlling the movement of the scanning galvanometer of the OCT system according to the working parameters, and scanning the tablet to obtain an OCT image of the tablet; Step 5: Calculate the coating thickness of the tablet according to the OCT image of the tablet.

2. The OCT real-time detection method for drug coating thickness suitable for assembly line according to claim 1, characterized in that: In step 1, tablets are obtained from the drug production line multiple times, and one tablet is obtained from the drug production line each time.

3. The OCT real-time detection method for drug coating thickness suitable for assembly line according to claim 1, characterized in that: In step 2, the process of calculating the detection position and detection length of the tablet is: Determining the shape and size of the tablet identified in the image; The detection position and detection length of the tablet are determined according to the shape and size of the tablet.

4. The OCT real-time detection method for drug coating thickness suitable for assembly line according to claim 3, characterized in that: The detection position of elliptical tablets is the straight line area between the two ends of the long axis of the medicine; the detection position of circular tablets with no concave-convex texture on the surface is the area between the two ends of any diameter of the circular upper surface of the tablet; the detection position of circular tablets with concave-convex texture on the surface is the area between the two ends of a specific diameter direction of the circular upper surface of the tablet set according to the texture shape; the detection position of triangular tablets is the area between the two ends of the straight line from the longest vertex on the triangular surface to the bottom edge; the detection position of diamond tablets is the straight line area between the two farthest vertices on the diamond upper surface.

5. The OCT real-time detection method for drug coating thickness suitable for assembly line according to claim 1, characterized in that: In step 5, the OCT image is analyzed using an image processing algorithm to determine the boundary of the coating layer of the tablet, and the distance from the tablet surface to the inner boundary of the coating layer is measured to obtain the coating thickness of the tablet.

6. The OCT real-time detection method for drug coating thickness suitable for assembly line according to claim 1, characterized in that: Step 2 is as follows: The number of the machine vision systems is two, namely a first machine vision system and a second machine vision system. The tablet moves on the inspection line and passes through the first machine vision system and the second machine vision system in sequence. The first machine vision system captures a first image containing a tablet, identifies the tablet from the first image, and calculates a detection position and a detection length of the tablet; The second machine vision system captures a second image containing the tablets, identifies the tablets from the second image, and calculates the placement angle, horizontal distance, and vertical distance of the tablets.

7. A drug coating thickness OCT real-time detection system suitable for production line, characterized in that: A method for performing real-time OCT detection of drug coating thickness applicable to an assembly line according to any one of claims 1 to 6, comprising: an inspection assembly line, and a tablet acquisition mechanism, a machine vision system and an OCT system sequentially arranged on the inspection assembly line, wherein the machine vision system and the OCT system are both connected to a computer system; The detection assembly line is used to move the tablets; The tablet acquisition mechanism is used to acquire tablets from the drug production line and place them on the testing line; The machine vision system is used to capture images containing tablets; The computer system is used to identify the tablets from the image, calculate the detection position, detection length, placement angle, horizontal distance and vertical distance of the tablets; generate OCT system working parameters according to the detection position, detection length, placement angle, horizontal distance and vertical distance of each tablet; calculate the coating thickness of the tablets according to the OCT images of the tablets; The placement angle is the angle between the detection position and the scanning direction of the OCT system; The moving direction of the tablet is the horizontal direction, and the scanning direction of the scanning galvanometer of the OCT system is the vertical direction; When the tablet is the first tablet, the horizontal distance of its position is the horizontal distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet, and the vertical distance of its position is the vertical distance between the starting position of the scanning galvanometer and the starting point of the detection position of the first tablet; When the tablet is not the first tablet, the horizontal distance of its position is the horizontal distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet, and the vertical distance of its position is the vertical distance between the end point of the detection position of the previous tablet and the starting point of the detection position of the tablet; When the tablet identified in the image is the first tablet, the working parameters of the OCT system are calculated using formula (1): （1） in, represents the scanning speed of the OCT system for the first tablet, Indicates the forward speed of the tablet, Indicates the placement angle of the first tablet. Indicates the start time of the OCT system. Indicates the horizontal distance corresponding to the position of the first pill, Indicates the vertical distance corresponding to the position of the first tablet, Indicates the scanning time of the first tablet, Indicates the detection length of the first tablet; When the tablet identified in the image is not the first tablet, the working parameters of the OCT system are calculated by formula (2): （2） in, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The duration of the starting point of the detection position of each pill, Indicates The end point of the detection position of the first tablet to the The horizontal distance between the starting points of the detection positions of the tablets, Indicates that the scanning point of the OCT system is from The end point of the detection position of the first tablet moves to the The speed of the starting point of the detection position of each tablet, Indicates The end point of the detection position of the first tablet to the The vertical distance between the starting points of the detection positions of the tablets, Indicates the OCT system Scanning speed of each tablet, Indicates The angle of placement of pills, Indicates The scanning time of each pill, Indicates The detection length of each tablet, ; The OCT system is used to control the movement of its scanning galvanometer according to the working parameters and scan the tablet.

Images