A chip identification and positioning algorithm based on coordinate system transformation

Abstract

The present invention discloses a chip recognition and positioning algorithm based on coordinate system conversion, which analyzes and processes the collected image data and converts the position of the unmounted chip, and the present invention relates to the field of mounted chip recognition technology. The chip recognition and positioning algorithm based on coordinate system conversion sets the mounted chip coordinate system according to the marked mounted chip position, and then sets the module coordinate system corresponding to the camera field of view, and obtains the conversion matrix of the two coordinate systems based on the known position of the mounted chip in the mounted chip coordinate system and the coordinate position in the module coordinate system, so as to realize all-round recognition of the mounting area, realize the coordinate conversion between the chip coordinate system and the module coordinate system, and optimize the deviation angle between the two coordinates according to the coordinates of the mounted chip, so as to improve the subsequent positioning of the unmounted chip position, complete the fast and accurate mounting recognition and positioning operation, and improve the efficiency of the operation.

Description

Technical Field

[0001] The present invention relates to the technical field of chip mounting identification, and in particular to a chip identification and positioning algorithm based on coordinate system conversion. Background Art

[0002] In order to improve production efficiency, an efficient recognition algorithm is needed to guide the operation of the sorting machine and realize the operation of mounting the chip on the substrate.

[0003] The reference patent name is: A method, device, equipment and storage medium for screening bare chips (patent publication number: CN114798479B, patent publication date: 2024-12-03). The screening method includes: obtaining a first image in the wafer to be screened, wherein the first image is an image of the bare chip distribution in the wafer to be screened; based on the first image, establishing a coordinate system, and obtaining the coordinate value of each bare chip in the wafer to be screened according to the coordinate system; based on each coordinate value, obtaining a second image in the wafer to be screened, wherein the second image is an image of the bare chips in the wafer to be screened; identifying the second image, and judging whether the second image is an image of a bare chip with a complete appearance, and obtaining a judgment result; according to the judgment result, determining whether the bare chip corresponding to the second image is complete, and performing a screening operation on the bare chip, thereby realizing the intelligent bare chip screening, improving the screening efficiency, improving the screening accuracy, and improving the utilization rate of defective products.

[0004] Based on the description in the above-mentioned document, in the existing chip mounting and identification operation, the sorting machine still takes the chips one by one at set intervals to perform the operation. However, in the actual process, some chips may have position deviations or chips may be missing. If the traditional settings are still used, it is easy to cause incomplete identification, resulting in low mounting accuracy and even mounting gaps. For this reason, the present invention provides a chip identification and positioning algorithm based on coordinate system transformation. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a chip identification and positioning algorithm based on coordinate system transformation, which solves the problem that in the existing chip mounting identification operation, the sorting machine still takes the chips one by one at a set interval to perform the operation, but in the actual process, some chips may have position deviations or missing chips. If the traditional settings are still used, it is easy to cause incomplete identification, resulting in low mounting accuracy and even mounting gaps.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a chip identification and positioning algorithm based on coordinate system transformation, specifically comprising the following steps:

[0007] A1. Use a camera set just above the placement operation to collect the distribution of the mounted chips, and realize multiple collection operations by moving the camera. The collected data is transmitted and stored in the database at the same time;

[0008] A2. Analyze and process the collected image data and convert the position of the unmounted chip, specifically including the following steps:

[0009] a21. Implement preprocessing operations on the collected image data, determine the feature content located at the mounted chip and mark it;

[0010] a22. Set the chip mount coordinate system according to the marked chip mount position, and then set the module coordinate system corresponding to the camera field of view, and obtain the conversion matrix of the two coordinate systems based on the known position of the chip mount in the chip mount coordinate system and the coordinate position in the module coordinate system;

[0011] a23. Based on the known position coordinates of the unmounted chip in the chip coordinate system, the position coordinates in the corresponding module coordinate system are obtained by introducing the position coordinates into the conversion matrix of the coordinate system;

[0012] A3. Extract the position coordinates in the module coordinate system and transmit them to the execution terminal to implement path planning operations and placement.

[0013] Preferably, the preprocessing operation on the collected image data in a21 is:

[0014] B1. Grayscale processing is performed on each collected image data, and multiple pixels are set in the image data, and different features are determined according to the change of the grayscale value of the pixel points;

[0015] B2. extracting the historical feature parts of the mounted chip from the database, matching the divided different features with the extracted feature parts of the mounted chip to determine the feature parts of the mounted chip in the image data;

[0016] B3, marking the determined characteristic parts of the mounted chip according to the serial numbers, retaining the image data with the characteristic parts of the mounted chip, and removing the image data without the characteristic parts of the mounted chip;

[0017] B4. Based on the order and orientation of image acquisition, the image data with the characteristic part of the mounted chip is spliced ​​to form an image with a complete mounting area marked as M.

[0018] Preferably, the operation of splicing the image data with the characteristic part of the mounted chip in B4 is:

[0019] b41, the camera moves to the next acquisition and retains the characteristic part of the last row of mounted chips in the previous image data located in the moving direction each time;

[0020] b42, determining the image data according to the acquired azimuth order, and removing the subsequent part of the preceding image data located at the characteristic part of the last row of the mounted chip, and removing the preceding part of the subsequent image data located at the characteristic part of the last row of the mounted chip, and leaving the corresponding characteristic parts of the mounted chip in the adjacent image data for overlay alignment;

[0021] b43. The image data are finally stitched together in sequence to form an image M with a complete mounting area.

[0022] Preferably, the setting operation of the chip mounting coordinate system in a22 is:

[0023] C1, based on the image M, select the marked chip feature part in the lower left corner as the origin, and then establish X based on the existing chip feature part a Axis and Y a axis;

[0024] C2, find the chip feature part adjacent to the origin in C1, determine the chip feature that does not contain other chip feature parts in all areas below the adjacent chip feature part, and establish X from the origin to the current chip feature. a Axis, and then determine the direction of the Y axis from the origin, which is located in the plane where the chip feature part is located and is 90° to the X axis and contains the chip feature part a axis;

[0025] C3. Set the coordinates of the feature part of the mounted chip in the chip coordinate system and mark it as (nx a ,my a ), while nx a Corresponding to X a The distance between the nth chip position in the axis direction and the origin of the chip coordinate system, my a Corresponding to Y a The distance between the mth chip placement position in the axis direction and the origin of the chip placement coordinate system, and when initially set, it is located at X a The spacing between adjacent chip placement positions on the axis is equal and the distance is x a , located in Y a The spacing between adjacent chip mounting positions on the axis is equal and the distance is y a .

[0026] Preferably, the setting operation of the module coordinate system in a22 is:

[0027] D1, based on the image M, select the lower left corner of the image edge as the origin of the module coordinate system, and then establish the X coordinate system according to the edge boundary of the image. b Axis and Y b axis;

[0028] D2, establish an X-axis from the origin in D1 to the bottom edge of the image. b Axis, and determine the X b The Y axis is established at the left edge line extending in the direction of 90° b axis, and all chip features are located on the X b Axis and Y b In the first quadrant where the axes intersect;

[0029] D3. Set the coordinates of the chip feature part located in the module coordinate system and mark it as (nx b ,my b ), and when initially set, it is located at X b The spacing between adjacent chip placement positions on the axis is equal and the distance is x b , located in Y b The spacing between adjacent chip mounting positions on the axis is equal and the distance is y b .

[0030] Preferably, the transformation matrix of the two coordinate systems in a22 is obtained as follows:

[0031] E1. Select the same multiple mounted chip features in the camera field of view, and the coordinates in the chip coordinate system are P a (nx a ,my a ), the corresponding coordinate in the module coordinate system is Q b (nx b ,my b );

[0032] E2, and select the same point Pk, and the origin in the chip coordinate system is located at the coordinate of the module coordinate system (jx a ,ky a ), and extract the features of the mounted chips with multiple mounted points to calculate the change in the angle between the two coordinate systems;

[0033] E3. Based on the final angle value, the transformation matrix of the two coordinate systems is:

[0034] ;

[0035] Q b is the coordinate representation of the point in the module coordinate system, P a is the coordinate of the midpoint of the chip coordinate system, λ is the ratio of the two coordinate systems, α is the deviation angle between the chip coordinate system and the module coordinate system, jx a andky aIt is the difference between the origin of the chip coordinate system and the axis of the module coordinate system in the module coordinate system.

[0036] Preferably, the angle calculation formula between the two coordinate systems in E2 is:

[0037] ;

[0038] α g is the deviation angle between the gth chip coordinate system and the module coordinate system, nx a The distance Y between the points on the current chip and the chip coordinate system a The distance between the Y axis and the chip point. L1 is the distance between the chip point and the vertical Y axis. a Axis direction α g Angle to Y a The distance between the axes;

[0039] L1=nx b -jx a -L2;

[0040] nx b The chip has been attached to the Y position in the module coordinate system. b Axis distance, jx a The origin of the chip coordinate system is located in the module coordinate system to Y b The distance between the chip and the vertical Y axis, and L2 is the distance between the chip and the vertical Y axis. a Axis direction α g Angle and to the chip coordinate system origin and Y b The axis distance parallel to the axis minus the deviation of the current chip point from the vertical Y a Axis direction α g Angle and Y a The difference in axis distances;

[0041] L2=tanα g ×(my b -ky a );

[0042] my b The chip has been attached to the X b Axis distance, ky a The origin of the chip coordinate system is located in the module coordinate system to X b The distance between the axes;

[0043] Then combine the square relationship formula of tangent and cosine: ;

[0044] Based on the above, the angle α between the coordinate systems is obtained g , and the average angle α is calculated based on the angle values ​​obtained multiple times 平 .

[0045] Preferably, the average angle α 平 The calculation formula is:

[0046] α 平 =(α1+α2+…+α g ) / g;

[0047] And g is the number of angles for realizing the average value calculation.

[0048] Preferably, the operation of solving the coordinates of the position of the unmounted chip in the corresponding module coordinate system in a23 is:

[0049] F1. Determine the coordinates of the unmounted chip position in the chip coordinate system;

[0050] F2. Then, the determined coordinates of the chip coordinate system are introduced into the transformation matrix, and the position coordinates in the corresponding module coordinate system are deduced inversely by combining the calculation formula for calculating the angle.

[0051] Preferably, the operation steps of A3 to implement path planning are:

[0052] a31. The position coordinates obtained in the module coordinate system are transmitted to the execution terminal, and then the execution terminal grabs the chip by moving the placement unit with a camera;

[0053] a32, aligning the captured chip with the coordinate position in the camera field of view, and realizing the mobile reset operation of the placement unit to complete the placement;

[0054] a33. After each chip mounting is completed, the image data is updated.

[0055] The present invention provides a chip identification and positioning algorithm based on coordinate system transformation. Compared with the prior art, it has the following beneficial effects:

[0056] (1) The chip recognition and positioning algorithm based on coordinate system conversion sets the mounting chip coordinate system according to the marked mounting chip position, and then sets the module coordinate system corresponding to the camera field of view, and obtains the conversion matrix of the two coordinate systems based on the known position of the mounting chip in the mounting chip coordinate system and the coordinate position in the module coordinate system, thereby realizing all-round recognition of the mounting area, realizing the coordinate conversion between the chip coordinate system and the module coordinate system, and optimizing the deviation angle between the two coordinates according to the coordinates of the mounted chip, thereby improving the subsequent positioning of the unmounted chip position, completing the fast and accurate mounting recognition and positioning operation, and improving the efficiency of the operation.

[0057] (2) The chip recognition and positioning algorithm based on coordinate system transformation determines the image data according to the order of the collected orientation, removes the subsequent part of the previous image data located at the characteristic part of the last row of the mounted chip, and removes the preceding part of the subsequent image data located at the characteristic part of the last row of the mounted chip, and aligns the corresponding characteristic parts of the mounted chip in the remaining adjacent image data, thereby forming an image with a completed mounting area for the collected image data, so as to better identify the unmounted position, complete more accurate coordinate identification, and reduce the matching error rate of the corresponding position, so as to make the subsequent positioning more accurate.

[0058] (3) The chip identification and positioning algorithm based on coordinate system transformation determines the position coordinates of the unmounted chip in the chip coordinate system, then introduces the determined coordinates of the chip coordinate system into the transformation matrix, and combines the calculation formula for calculating the angle to infer the position coordinates in the corresponding module coordinate system, thereby improving the scope of application of the algorithm, not limited to the mounting operation under a single spacing, and improving the fault tolerance rate, which can effectively complete the path planning and completion operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is an operational flow chart of the recognition algorithm of the present invention;

[0060] Figure 2 This is an operational flow chart of image preprocessing of the present invention;

[0061] Figure 3 It is a schematic diagram of image stitching of the present invention;

[0062] Figure 4 is a schematic diagram of the module coordinate system of the present invention;

[0063] Figure 5 is a schematic diagram of the chip coordinate system of the present invention;

[0064] Figure 6 It is a schematic diagram of the connection between the module coordinate system and the chip coordinate system of the present invention. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] See also Figure 1-Figure 6 The present invention provides a technical solution: a chip identification and positioning algorithm based on coordinate system transformation, which specifically includes the following steps:

[0067] A1. Use a camera set just above the placement operation to collect the distribution of the mounted chips, and realize multiple collection operations by moving the camera. The collected data is transmitted and stored in the database at the same time;

[0068] A2. Analyze and process the collected image data and convert the position of the unmounted chip, specifically including the following steps:

[0069] a21. Implement preprocessing operations on the collected image data, determine the feature content located at the mounted chip and mark it;

[0070] a22. Set the chip mount coordinate system according to the marked chip mount position, and then set the module coordinate system corresponding to the camera field of view, and obtain the conversion matrix of the two coordinate systems based on the known position of the chip mount in the chip mount coordinate system and the coordinate position in the module coordinate system;

[0071] a23. Based on the known position coordinates of the unmounted chip in the chip coordinate system, the position coordinates in the corresponding module coordinate system are obtained by introducing the position coordinates into the conversion matrix of the coordinate system;

[0072] A3. Extract the position coordinates in the module coordinate system and transmit them to the execution terminal to implement path planning operations and placement.

[0073] By setting the mounting chip coordinate system according to the marked mounting chip position, and then setting the module coordinate system corresponding to the camera field of view, and deriving the conversion matrix of the two coordinate systems based on the known position of the mounting chip in the mounting chip coordinate system and the coordinate position in the module coordinate system, all-round recognition of the mounting area is achieved, and the coordinate transformation between the chip coordinate system and the module coordinate system is realized. The deviation angle between the two coordinates is optimized according to the coordinates of the mounted chip, thereby improving the subsequent positioning of the unmounted chip position, completing fast and accurate mounting identification and positioning operations, and improving operation efficiency.

[0074] In the embodiment of the present invention, the preprocessing operation of the collected image data in a21 is:

[0075] B1. Grayscale processing is performed on each collected image data, and multiple pixels are set in the image data, and different features are determined according to the change of the grayscale value of the pixel points;

[0076] B2. extracting the historical feature parts of the mounted chip from the database, matching the divided different features with the extracted feature parts of the mounted chip to determine the feature parts of the mounted chip in the image data;

[0077] B3, marking the determined characteristic parts of the mounted chip according to the serial numbers, retaining the image data with the characteristic parts of the mounted chip, and removing the image data without the characteristic parts of the mounted chip;

[0078] B4. Based on the order and orientation of image acquisition, the image data with the characteristic part of the mounted chip is spliced ​​to form an image with a complete mounting area marked as M.

[0079] The grayscale processing of images is an existing mature technology, and the boundary points of the features are determined according to the changes in the grayscale values, and then different feature parts are determined and divided according to the boundary points. Figure 3 shown.

[0080] In the embodiment of the present invention, the operation of splicing the image data with the characteristic portion of the mounted chip in B4 is:

[0081] b41, the camera moves to the next acquisition and retains the characteristic part of the last row of mounted chips in the previous image data located in the moving direction each time;

[0082] b42, determining the image data according to the acquired azimuth order, and removing the subsequent part of the preceding image data located at the characteristic part of the last row of the mounted chip, and removing the preceding part of the subsequent image data located at the characteristic part of the last row of the mounted chip, and leaving the corresponding characteristic parts of the mounted chip in the adjacent image data for overlay alignment;

[0083] b43. The image data are finally stitched together in sequence to form an image M with a complete mounting area.

[0084] By determining the image data according to the collected azimuth order, removing the subsequent part of the previous image data located at the characteristic part of the chip mounted in the last row, and removing the preceding part of the subsequent image data located at the characteristic part of the chip mounted in the last row, and overlaying and aligning the corresponding characteristic parts of the chip mounted in the remaining adjacent image data, it is possible to form an image with a completed mounting area for the collected image data, so as to better identify the unmounted position, complete more accurate coordinate identification, and reduce the matching error rate of the corresponding position, so as to make the subsequent positioning more accurate.

[0085] See also Figure 5 In the embodiment of the present invention, the setting operation of the chip mounting coordinate system in a22 is:

[0086] C1, based on the image M, select the marked chip feature part in the lower left corner as the origin, and then establish X based on the existing chip feature part a Axis and Y a axis;

[0087] C2, find the chip feature part adjacent to the origin in C1, determine the chip feature that does not contain other chip feature parts in all areas below the adjacent chip feature part, and establish X from the origin to the current chip feature. a Axis, and then determine the direction of the Y axis from the origin, which is located in the plane where the chip feature part is located and is 90° to the X axis and contains the chip feature part a axis;

[0088] C3. Set the coordinates of the feature part of the mounted chip in the chip coordinate system and mark it as (nx a ,my a ), while nx a Corresponding to X a The distance between the nth chip position in the axis direction and the origin of the chip coordinate system, my a Corresponding to Y a The distance between the mth chip placement position in the axis direction and the origin of the chip placement coordinate system, and when initially set, it is located at X a The spacing between adjacent chip placement positions on the axis is equal and the distance is x a , located in Y a The spacing between adjacent chip mounting positions on the axis is equal and the distance is y a .

[0089] See also Figure 4 In the embodiment of the present invention, the setting operation of the module coordinate system in a22 is:

[0090] D1, based on the image M, select the lower left corner of the image edge as the origin of the module coordinate system, and then establish the X coordinate system according to the edge boundary of the image. b Axis and Y b axis;

[0091] D2, establish an X-axis from the origin in D1 to the bottom edge of the image. b Axis, and determine the X b The Y axis is established at the left edge line extending in the direction of 90° b axis, and all chip features are located on the X b Axis and Y b In the first quadrant where the axes intersect;

[0092] D3. Set the coordinates of the chip feature part located in the module coordinate system and mark it as (nx b ,my b ), and when initially set, it is located at X b The spacing between adjacent chip placement positions on the axis is equal and the distance is x b , located in Y bThe spacing between adjacent chip mounting positions on the axis is equal and the distance is y b .

[0093] See also Figure 6 In the embodiment of the present invention, the transformation matrix of the two coordinate systems in a22 is obtained as follows:

[0094] E1. Select the same multiple mounted chip features in the camera field of view, and the coordinates in the chip coordinate system are P a (nx a ,my a ), the corresponding coordinate in the module coordinate system is Q b (nx b ,my b );

[0095] E2, and select the same point Pk, and the origin in the chip coordinate system is located at the coordinate of the module coordinate system (jx a ,ky a ), and extract the features of the mounted chips with multiple mounted points to calculate the change in the angle between the two coordinate systems;

[0096] E3. Based on the final angle value, the transformation matrix of the two coordinate systems is:

[0097] ;

[0098] Q b is the coordinate representation of the point in the module coordinate system, P a is the coordinate of the midpoint of the chip coordinate system, λ is the ratio of the two coordinate systems, α is the deviation angle between the chip coordinate system and the module coordinate system, jx a andky a It is the difference between the origin of the chip coordinate system and the axis of the module coordinate system in the module coordinate system.

[0099] In the embodiment of the present invention, the angle calculation formula between the two coordinate systems in E2 is:

[0100] ;

[0101] α g is the deviation angle between the gth chip coordinate system and the module coordinate system, nx a The distance Y between the points on the current chip and the chip coordinate system a The distance between the Y axis and the chip point. L1 is the distance between the chip point and the vertical Y axis. a Axis direction α g Angle and Y a The distance between the axes;

[0102] L1=nx b-jx a -L2;

[0103] nx b The chip has been attached to the Y position in the module coordinate system. b Axis distance, jx a The origin of the chip coordinate system is located in the module coordinate system to Y b The distance between the chip and the vertical Y axis, and L2 is the distance between the chip and the vertical Y axis. a Axis direction α g Angle and to the chip coordinate system origin and Y b The axis distance parallel to the axis minus the deviation of the current chip point from the vertical Y a Axis direction α g Angle and Y a The difference in axis distances;

[0104] L2=tanα g ×(my b -ky a );

[0105] my b The chip has been attached to the X b Axis distance, ky a The origin of the chip coordinate system is located in the module coordinate system to X b The distance between the axes;

[0106] Then combine the square relationship formula of tangent and cosine: ;

[0107] Based on the above, the angle α between the coordinate systems is obtained g , and the average angle α is calculated based on the angle values ​​obtained multiple times 平 .

[0108] In the embodiment of the present invention, the average angle α 平 The calculation formula is:

[0109] α 平 =(α1+α2+…+α g ) / g;

[0110] And g is the number of angles for realizing the average value calculation.

[0111] In the embodiment of the present invention, the operation of solving the coordinates of the position of the unmounted chip in the corresponding module coordinate system in a23 is:

[0112] F1. Determine the coordinates of the unmounted chip position in the chip coordinate system;

[0113] F2. Then, the determined coordinates of the chip coordinate system are introduced into the transformation matrix, and the position coordinates in the corresponding module coordinate system are deduced inversely by combining the calculation formula for calculating the angle.

[0114] In the embodiment of the present invention, the operation steps of A3 to implement path planning are:

[0115] a31. The position coordinates obtained in the module coordinate system are transmitted to the execution terminal, and then the execution terminal grabs the chip by moving the placement unit with a camera;

[0116] a32, aligning the captured chip with the coordinate position in the camera field of view, and realizing the mobile reset operation of the placement unit to complete the placement;

[0117] a33. After each chip mounting is completed, the image data is updated.

[0118] By determining the position coordinates of the unmounted chip in the chip coordinate system, and then introducing the determined coordinates of the chip coordinate system into the transformation matrix, and combining the calculation formula for calculating the angle, the position coordinates in the corresponding module coordinate system are inferred, thereby improving the scope of application of the algorithm, not limited to the mounting operation under a single spacing, and improving the fault tolerance rate, and being able to effectively complete the path planning and completion operation.

[0119] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0120] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0121] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A chip identification and positioning algorithm based on coordinate system transformation, characterized in that: The specific steps include: A1. Use a camera set just above the placement operation to collect the distribution of the mounted chips, and realize multiple collection operations by moving the camera. The collected data is transmitted and stored in the database at the same time; A2. Analyze and process the collected image data and convert the position of the unmounted chip, specifically including the following steps: a21. Implement preprocessing operations on the collected image data, determine the feature content located at the mounted chip and mark it; a22. Set the chip mount coordinate system according to the marked chip mount position, and then set the module coordinate system corresponding to the camera field of view, and obtain the conversion matrix of the two coordinate systems based on the known position of the chip mount in the chip mount coordinate system and the coordinate position in the module coordinate system; a23. Based on the known position coordinates of the unmounted chip in the chip coordinate system, the position coordinates in the corresponding module coordinate system are obtained by introducing the position coordinates into the conversion matrix of the coordinate system; A3. Extract the position coordinates in the module coordinate system and transmit them to the execution terminal to implement path planning operations and placement.

2. The chip identification and positioning algorithm based on coordinate system transformation according to claim 1, characterized in that: The preprocessing operation of the collected image data in a21 is: B1. Grayscale processing is performed on each collected image data, and multiple pixels are set in the image data, and different features are determined according to the change of the grayscale value of the pixel points; B2. extracting the historical feature parts of the mounted chip from the database, matching the divided different features with the extracted feature parts of the mounted chip to determine the feature parts of the mounted chip in the image data; B3, marking the determined characteristic parts of the mounted chip according to the serial numbers, retaining the image data with the characteristic parts of the mounted chip, and removing the image data without the characteristic parts of the mounted chip; B4. Based on the order and orientation of image acquisition, the image data with the characteristic part of the mounted chip is spliced ​​to form an image with a complete mounting area marked as M.

3. The chip identification and positioning algorithm based on coordinate system transformation according to claim 2, characterized in that: The operation of splicing the image data with the characteristic part of the mounted chip in B4 is: b41, the camera moves to the next acquisition and retains the characteristic part of the last row of mounted chips in the previous image data located in the moving direction each time; b42, determining the image data according to the acquired azimuth order, and removing the subsequent part of the preceding image data located at the characteristic part of the last row of the mounted chip, and removing the preceding part of the subsequent image data located at the characteristic part of the last row of the mounted chip, and leaving the corresponding characteristic parts of the mounted chip in the adjacent image data for overlay alignment; b43. The image data are finally stitched together in sequence to form an image M with a complete mounting area.

4. The chip identification and positioning algorithm based on coordinate system transformation according to claim 3 is characterized in that: The setting operation of the chip mounting coordinate system in a22 is: C1, based on the image M, select the marked chip feature part in the lower left corner as the origin, and then establish X based on the existing chip feature part a Axis and Y a axis; C2, find the chip feature part adjacent to the origin in C1, determine the chip features located below the adjacent chip feature part and do not contain other chip feature parts, and establish X from the origin to the current chip feature. a Axis, and then determine the direction of the Y axis from the origin, which is located in the plane where the chip feature part is located and is 90° to the X axis and contains the chip feature part a axis; C3. Set the coordinates of the feature part of the mounted chip in the chip coordinate system and mark it as (nx a ,my a ), while nx a Corresponding to X a The distance between the nth chip position in the axis direction and the origin of the chip coordinate system, my a Corresponding to Y a The distance between the mth chip position in the axis direction and the origin of the chip coordinate system, and when initially set, it is located at X a The spacing between adjacent chip placement positions on the axis is equal and the distance is x a , located in Y a The spacing between adjacent chip mounting positions on the axis is equal and the distance is y a .

5. The chip identification and positioning algorithm based on coordinate system transformation according to claim 4 is characterized in that: The setting operation of the module coordinate system in a22 is: D1, based on the image M, select the lower left corner of the image edge as the origin of the module coordinate system, and then establish the X coordinate system according to the edge boundary of the image. b Axis and Y b axis; D2, establish an X from the origin in D1 to the lower edge of the image. b Axis, and determine the X b The Y axis is established at the left edge line extending in the direction of 90° b axis, and all chip features are located on the X b Axis and Y b In the first quadrant where the axes intersect; D3. Set the coordinates of the chip feature part located in the module coordinate system and mark it as (nx b ,my b ), and when initially set, it is located at X b The spacing between adjacent chip placement positions on the axis is equal and the distance is x b , located in Y b The spacing between adjacent chip mounting positions on the axis is equal and the distance is y b .

6. The chip identification and positioning algorithm based on coordinate system transformation according to claim 5, characterized in that: The transformation matrix of the two coordinate systems in a22 is obtained as follows: E1. Select the same multiple mounted chip features in the camera field of view, and the coordinates in the chip coordinate system are P a (nx a ,my a ), the corresponding coordinate in the module coordinate system is Q b (nx b ,my b ); E2, and select the same point Pk, and the origin in the chip coordinate system is located at the coordinate of the module coordinate system (jx a ,ky a ), and extract the features of the mounted chips with multiple mounted points to calculate the change in the angle between the two coordinate systems; E3. Based on the final angle value, the transformation matrix of the two coordinate systems is: ； Q b is the coordinate representation of the point in the module coordinate system, P a is the coordinate of the midpoint of the chip coordinate system, λ is the ratio of the two coordinate systems, α is the deviation angle between the chip coordinate system and the module coordinate system, jx a andky a It is the difference between the origin of the chip coordinate system and the axis of the module coordinate system in the module coordinate system.

7. The chip identification and positioning algorithm based on coordinate system transformation according to claim 6 is characterized in that: The angle calculation formula between the two coordinate systems in E2 is: ； α g is the deviation angle between the gth chip coordinate system and the module coordinate system, nx a The distance Y between the points on the current chip and the chip coordinate system a The distance between the Y axis and the chip point. L1 is the distance between the chip point and the vertical Y axis. a Axis direction α g Angle to Y a The distance between the axes; L1=nx b -jx a -L2; nx b The chip has been attached to the Y position in the module coordinate system. b Axis distance, jx a The origin of the chip coordinate system is located in the module coordinate system to Y b The distance between the chip and the vertical Y axis, and L2 is the distance between the chip and the vertical Y axis. a Axis direction α g Angle and to the chip coordinate system origin and Y b The axis distance parallel to the axis minus the deviation of the current chip point from the vertical Y a Axis direction α g Angle to Y a The difference in axis distances; L2=tanα g ×(my b -ky a ); my b The chip has been attached to the X b Axis distance, ky a The origin of the chip coordinate system is located in the module coordinate system to X b The distance between the axes; Then combine the square relationship formula of tangent and cosine: ; The angle α between the coordinate systems is obtained g , and the average angle α is calculated based on the angle values ​​obtained multiple times 平 .

8. The chip identification and positioning algorithm based on coordinate system transformation according to claim 7, characterized in that: The average angle α 平 The calculation formula is: α 平 =（α1+α2+…+α g ） / g； And g is the number of angles for realizing the average value calculation.

9. The chip identification and positioning algorithm based on coordinate system transformation according to claim 8, characterized in that: The operation of solving the coordinates of the unmounted chip position in the corresponding module coordinate system in a23 is: F1. Determine the coordinates of the unmounted chip position in the chip coordinate system; F2. Then, the determined coordinates of the chip coordinate system are introduced into the transformation matrix, and the position coordinates in the corresponding module coordinate system are deduced inversely by combining the calculation formula for calculating the angle.

10. The chip identification and positioning algorithm based on coordinate system transformation according to claim 1, characterized in that: The operation steps of A3 to implement path planning are: a31. The position coordinates obtained in the module coordinate system are transmitted to the execution terminal, and then the execution terminal grabs the chip by moving the placement unit with a camera; a32, aligning the captured chip with the coordinate position in the camera field of view, and realizing the mobile reset operation of the placement unit to complete the placement; a33. After each chip mounting is completed, the image data is updated.

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