A tire engraving device, system and method based on a three-dimensional galvanometer

Abstract

This invention relates to a tire engraving device, system, and method based on a three-dimensional galvanometer. The device includes a housing containing a laser and a three-dimensional galvanometer, with the laser and galvanometer optically connected. The laser receives control commands from a host computer and initializes itself, and generates and outputs a corresponding laser beam to the galvanometer based on the commands. The galvanometer deflects and controls the received laser beam according to the engraving file sent by the host computer, ensuring that the laser beam emitted from the galvanometer illuminates the tire surface and engraves it. This invention effectively avoids defects caused by human error, accurately engraves the desired areas on the tire sidewall, improves tire production quality, and significantly increases the engraving efficiency of the tire sidewall compared to a two-dimensional laser scanner, thus ensuring product consistency. Furthermore, for white tire sidewalls, the cover rubber can be directly removed, ensuring a smooth and fine surface.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser processing technology, in particular to a tire engraving device, system and method based on a three-dimensional galvanometer. BACKGROUND

[0002] Automobile tires are safety-related products. For product life cycle management and appearance beautification, etc., more and more tire sidewalls need to be engraved (subtractive processing: including marking, polishing, etc.).

[0003] In terms of product life cycle management, the tire sidewall needs to form identification such as cycle code, flow code, DOT code, mark, two-dimensional code, etc. In the past, tire manufacturing enterprises used inlaid separately made inserts on tire molds to form tire sidewall identification, but the inserts were relatively cumbersome to make, and regular replacement was prone to inlay number errors or poor inlay quality, which affected tire quality. In the prior art, two-dimensional laser scanners are also used for processing, but since the laser scanner is two-dimensional scanning and needs to be combined with an external driving mechanism (such as a robot) for three-dimensional control of the laser, it is not only costly, but also due to the two-dimensional scanner which can only scan in a two-dimensional plane, combined with a robot for control, not only is the scanning efficiency low, but also the calculation is complex, resulting in slow overall engraving process, low efficiency and high cost.

[0004] In addition, in terms of appearance beautification, for some high-end cars, ceremonial vehicles and specific types of vehicles, the tire sidewall needs to be decorated differently from other parts of the outer tire surface to add beauty. Among them, the white rubber decoration is commonly known as white sidewall tire. The previous process is to manually polish the covering rubber on the decorative rubber sheet to expose the white sidewall, which is not easy to ensure the fine and smooth surface of the white rubber. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a tire engraving device, system and method based on a three-dimensional galvanometer to solve the above problems of the prior art.

[0006] The technical solution of the present application to solve the above technical problem is as follows: a tire engraving device based on a three-dimensional galvanometer, comprising a housing, a laser and a three-dimensional galvanometer arranged in the housing, the laser being connected in optical path with the three-dimensional galvanometer;

[0007] The laser is used to receive control commands from an upper computer and initialize, and control corresponding laser beams to be generated and output to the three-dimensional galvanometer according to the control commands;

[0008] The three-dimensional galvanometer deflects and controls the received laser beams according to the engraving file sent by the upper computer, so that the laser beams emitted from the three-dimensional galvanometer irradiate the tire surface and engrave the tire surface.

[0009] The application also provides a tire engraving system based on a three-dimensional galvanometer, comprising a host computer and the tire engraving device, and the host computer is electrically connected with the laser and the three-dimensional galvanometer through a laser control card.

[0010] The host computer analyzes a pre-acquired tire physical data model, acquires a relative position relationship between a tire positioning mark coordinate and a pattern to be engraved, and determines a target tire sidewall engraving position based on the relative position relationship.

[0011] The host computer determines a target tire sidewall point cloud based on a pre-acquired initial tire sidewall point cloud, and performs tire character segmentation through flat area filtering processing and a Euclidean space clustering algorithm based on the target tire sidewall point cloud; wherein the flat area filtering processing refers to filtering out point clouds corresponding to flat areas from the target tire sidewall point cloud, and only retaining character point clouds.

[0012] The host computer determines an engraving position of an engraved character based on character recognition, and generates an engraving file containing the engraving position according to character point cloud coordinates and a rotation angle and an offset position of engraving content.

[0013] The application also provides a tire engraving method based on a three-dimensional galvanometer, comprising the following steps:

[0014] The host computer analyzes a pre-acquired tire physical data model, acquires a relative position relationship between a tire positioning mark coordinate and a pattern to be engraved, and determines a target tire sidewall engraving position based on the relative position relationship.

[0015] The host computer determines a target tire sidewall point cloud based on a pre-acquired initial tire sidewall point cloud, and performs tire character segmentation through flat area filtering processing and a Euclidean space clustering algorithm based on the target tire sidewall point cloud; wherein the flat area filtering processing refers to filtering out point clouds corresponding to flat areas from the target tire sidewall point cloud, and only retaining character point clouds.

[0016] The host computer determines an engraving position of an engraved character based on character recognition, and generates an engraving file containing the engraving position according to character point cloud coordinates and a rotation angle and an offset position of engraving content.

[0017] The tire engraving device, system and method based on the three-dimensional galvanometer of the present application can effectively avoid the occurrence of operation failure caused by human operation, accurately perform laser engraving on the position to be engraved on the tire sidewall, improve the tire production quality, greatly improve the engraving efficiency of the tire sidewall compared with the two-dimensional laser scanner, and is beneficial to ensuring the consistency of products. In addition, for the white tire sidewall, the covering glue on the decorative glue sheet can be directly engraved and removed, and the white sidewall is exposed, so that the white glue surface is fine and smooth. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 FIG. 1 is a structural schematic diagram of a tire engraving device based on a three-dimensional galvanometer according to an embodiment of the present application;

[0019] Figure 2 FIG. 2 is a structural schematic diagram of a tire engraving system based on a three-dimensional galvanometer according to an embodiment of the present application;

[0020] Figure 3 FIG. 3 is a flow schematic diagram of a tire engraving method based on a three-dimensional galvanometer according to an embodiment of the present application.

[0021] In the drawings, the components represented by the respective reference numerals are listed as follows:

[0022] 1, housing, 2, laser, 3, three-dimensional galvanometer. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0024] As shown in FIG. 1, a tire engraving device based on a three-dimensional galvanometer includes a housing 1, a laser 2 and a three-dimensional galvanometer 3 are arranged in the housing 1, and the laser 2 is connected with the three-dimensional galvanometer 3 in an optical path. Figure 1

[0025] The laser 2 is used to receive a control command of a host computer and initialize, and control a corresponding laser beam to be generated and output to the three-dimensional galvanometer 3 according to the control command.​

[0026] The three-dimensional galvanometer 3 deflects and controls the received laser beam according to the carving file sent by the host computer, so that the laser beam emitted from the three-dimensional galvanometer 3 irradiates the tire surface and carves the tire surface.

[0027] In practice, the laser 2 and the three-dimensional galvanometer 3 are installed in the shell 1 to ensure that the laser emitted by the laser 1 is completely received by the three-dimensional galvanometer 3, and the shell 1 is provided with a light outlet, and the laser beam emitted by the three-dimensional galvanometer 3 is emitted through the light outlet and irradiates the tire surface to carve.

[0028] In order to ensure better working effect, it is also necessary to cooperate with the cooler, and the cooling pipe of the water cooler cools and cools the laser and the laser carving head 5, improves the stability of the working of the laser 2 and the three-dimensional galvanometer 3, and also ensures the safety of the whole equipment operation.

[0029] As shown in Figure 2 The application also provides a tire carving system based on a three-dimensional galvanometer, which comprises a host computer and the tire carving device, and the host computer is electrically connected with the laser 2 and the three-dimensional galvanometer 3 through a laser control card.

[0030] The host computer analyzes the tire physical data model obtained in advance, obtains the relative position relationship between the tire positioning mark coordinates and the pattern to be carved, and determines the target tire sidewall carving position based on the relative position relationship.

[0031] Here, corresponding tire physical data models can be established for tires of different sizes and specifications, such as through photographing, scanning or tire images, and then three-dimensional modeling is performed by using existing modeling software to obtain tire physical data models of each size and specification. When carving, the corresponding tire physical data model is selected in advance according to the size and specification of the carved tire, and then analyzed to obtain the initial tire sidewall point cloud.

[0032] It should be noted that in the current embodiment, the region of interest is pre-selected, and the target tire sidewall point cloud required is segmented from the obtained initial tire sidewall point cloud according to the region of interest. The specific segmentation steps are described in the subsequent embodiments, and are not described in detail here.

[0033] The host computer determines the target tire sidewall point cloud based on the initial tire sidewall point cloud obtained in advance, and based on the target tire sidewall point cloud, performs tire character segmentation through flat area filtering processing and Euclidean space clustering algorithm.

[0034] It should be noted that the initial tire sidewall point can be placed in a set carving position for scanning acquisition based on different specification tires, the flat area filtering processing refers to filtering out the point cloud corresponding to the flat area from the target tire sidewall point cloud, only retaining the character point cloud, and the Euclidean space clustering algorithm refers to performing a Euclidean space clustering algorithm based on the retained character point cloud, so that each character point cloud can be completely segmented.

[0035] The host computer determines the carving position of the carved character based on the recognition of the character, and generates a carving file containing the carving position according to the character point cloud coordinates and the rotation angle and offset position of the carving content.

[0036] The calculation of the rotation angle of the carving content needs to determine the angle a of the character first according to the center and radius of the circle, and then obtain the relative angle b of the marked character, and determine the angle b+a of the rotation of the carving content according to the angle a of the character. Wherein, the angle of the rotation of the carving content will be further transmitted to the host computer, so that the host computer can adjust the light output angle of the etching laser emitted by the three-dimensional galvanometer 3 according to the angle of the rotation of the carving content.

[0037] In one or more embodiments of the present application, the specific implementation of the host computer based on the pre-acquired initial tire sidewall point cloud to determine the target tire sidewall point cloud is:

[0038] Determine a first point set of the pre-acquired initial tire sidewall point cloud, and when determining that a target point in the first point set is within the range covered by a preset region of interest, add the target point to a preset second point set;

[0039] Specifically, in the current embodiment, the x, y, and z ranges of the region of interest are set to (Xmin, Xmax), (Ymin, Ymax), and (Zmin, Zmax). Each point in the first point set is traversed, and during the traversal process, it is determined whether the X, Y, and Z values of the traversed point satisfy the following conditions:

[0040] Xmin < X < Xmax;

[0041] Ymin < Y < Ymax;

[0042] Zmin < Z < Zmax;

[0043] If it is determined that the above conditions are met, the traversed point is added to the preset second point set.

[0044] After determining that all target points are added, the target tire sidewall point cloud is determined based on the second point set.

[0045] In the above embodiment, the target tire sidewall point cloud required is segmented from the initial tire sidewall point cloud obtained according to the region of interest, so that the data amount of the point cloud is greatly reduced, the influence of noise is also reduced, and a good data foundation is provided for subsequent tire character positioning and segmentation.

[0046] In one or more embodiments of the present application, the host computer performs tire character segmentation based on the target tire sidewall point cloud by flat area filtering and Euclidean space clustering algorithm, and the specific implementation is as follows:

[0047] Based on the target tire sidewall point cloud, point cloud normal estimation is performed.

[0048] It should be noted that in the current embodiment, the specific implementation steps of point cloud normal estimation and extraction are not limited.

[0049] Based on the normal difference between the normal of the character region and the normal of the flat region, the point cloud corresponding to the flat region is filtered out from the target tire sidewall point cloud to obtain a character point cloud.

[0050] It should be noted that it can be known through practice and analysis that the normal of the character region and the normal of the flat region have a large difference, and in the current embodiment, based on this analysis result, the point cloud corresponding to the flat region is filtered out from the target tire sidewall point cloud based on the normal difference, and the character point cloud is retained.

[0051] In the specific implementation, in the current embodiment, a filtering algorithm based on the normal difference is performed. The specific algorithm flow is as follows:

[0052] First, take any point P in the target tire sidewall point cloud i , select different radius neighbors r1, r2, and calculate the normal n1, n2 of the point P i .

[0053] Then, according to the angle θ between the two normals n1, n2 of the point P i , filtering is performed, that is, whether the point P i belongs to a flat region is identified, and filtering is performed.

[0054] Finally, traverse other points and repeat the above two steps, and after the traversal is completed, the corresponding character point cloud is obtained.

[0055] Finally, set r1=1.5, r2=2, and obtain the filtered point cloud.

[0056] Based on the character point cloud, character component segmentation is performed by Euclidean space clustering algorithm.

[0057] Specifically, the Euclidean space clustering algorithm flow includes:

[0058] First, find a point P in space from the character point cloud i , find the nearest n points to him, judge the distance of the n points to P i . And put the points p1, p2, p3... with a distance less than the threshold r in set Q.

[0059] Then, find a point p1 in set Q and repeat the above steps to find the corresponding p 22 , p 23 , p 24 ...., and put them all into set Q.

[0060] Finally, when set Q can no longer have new points added, the search is complete, and each character point cloud is segmented.

[0061] In one or more embodiments of the present application, the determination of the engraving position of the engraved character is specifically implemented as:

[0062] Identify the character region from the segmented character point cloud;

[0063] In one embodiment, the number of points can be set to between 800 and 2000, and the size can be set to between 5 and 25, to complete the search and identification of the character.

[0064] Search and locate the engraved character around the character region, wherein the character and the engraved character have multiple fixed numbers with fixed lengths;

[0065] Specifically, the fixed numbers include factory number, specification, pattern, and brand. It should be noted that the position of the cycle number shown in the figure is the marking position. These fixed numbers all have fixed lengths.

[0066] According to the total fixed length of each fixed number and the center and radius of the character region, the engraving position of the engraved character is calculated.

[0067] In one or more embodiments of the present application, the determination of the center and radius of the character region is specifically implemented as:

[0068] Based on the target tire sidewall point cloud, z value dimension reduction processing is performed to obtain a dimension-reduced plane point cloud, wherein the plane point cloud has corresponding two-dimensional position information in a pre-established plane rectangular coordinate system;

[0069] Fitting the dimension-reduced plane point cloud obtains a corresponding point cloud curve;

[0070] Based on the two-dimensional position information corresponding to the point cloud curve, the tire radius and the tire center are determined;

[0071] The average z value of the character is used to update the z value of the tire center, and the tire radius and the updated tire center are used as the center and radius of the circle where the character is located.

[0072] As Figure 3 shown, the application also provides a tire engraving method based on a three-dimensional galvanometer, comprising the following steps:

[0073] S1: Analyzing a pre-acquired tire physical data model to obtain a relative position relationship between a tire positioning mark coordinate and a pattern to be engraved, and determining a target tire sidewall engraving position based on the relative position relationship;

[0074] It should be noted that in the current embodiment, a region of interest is pre-selected, and the target tire sidewall point cloud required is segmented from the initial tire sidewall point cloud obtained according to the region of interest. For specific segmentation steps, please refer to the subsequent embodiments, which are not described in detail here.

[0075] S2: Determining a target tire sidewall point cloud based on a pre-acquired initial tire sidewall point cloud, and performing tire character segmentation through flat area filtering processing and a Euclidean space clustering algorithm based on the target tire sidewall point cloud;

[0076] It should be noted that flat area filtering processing refers to filtering out point clouds corresponding to flat areas from the target tire sidewall point cloud, and only retaining character point clouds. The Euclidean space clustering algorithm refers to performing a Euclidean space clustering algorithm based on the retained character point clouds, so that each character point cloud can be completely segmented.

[0077] S3: Determining an engraving position of an engraved character based on character recognition, and generating an engraving file containing the engraving position according to the character point cloud coordinate and the rotation angle and offset position of the engraving content.

[0078] In one or more embodiments of the application, determining a target tire sidewall point cloud based on a pre-acquired initial tire sidewall point cloud specifically comprises the following steps:

[0079] S11: Determining a first point set of the pre-acquired initial tire sidewall point cloud, and adding a target point in the first point set to a pre-set second point set when the target point is within a range covered by a pre-set region of interest;

[0080] Specifically, in the current embodiment, the x, y, and z ranges of the region of interest are set as (Xmin, Xmax), (Ymin, Ymax), and (Zmin, Zmax). Each point in the first point set is traversed, and during the traversal process, it is determined whether the X, Y, and Z values of the traversed point satisfy the following conditions:

[0081] Xmin < X < Xmax;

[0082] Ymin < Y < Ymax;

[0083] Zmin < Z < Zmax;

[0084] If it is judged that each condition is satisfied, the traversal point is added to a preset second point set.

[0085] S12: After determining that all target points are added, a target tire sidewall point cloud is determined based on the second point set.

[0086] In one embodiment, (Xmin, Xmax) = (-100, 100), (Ymin, Ymax) = (100, 500), and (Zmin, Zmax) = (150, 200) can be set according to actual conditions.

[0087] In one or more embodiments of the present application, the tire character segmentation based on the target tire sidewall point cloud by the flat area filtering process and the Euclidean space clustering algorithm specifically includes the following steps:

[0088] S21: Based on the target tire sidewall point cloud, point cloud normal estimation is performed.

[0089] It should be noted that in the current embodiment, the point cloud normal estimation and extraction are not limited to specific implementation steps.

[0090] S22: Based on the normal difference between the normal of the character region and the normal of the flat region, the point cloud corresponding to the flat region is filtered out from the target tire sidewall point cloud to obtain a character point cloud.

[0091] It should be noted that it can be known through practice and analysis that the normal of the character region and the normal of the flat region have a large difference. In the current embodiment, based on this analysis result, the point cloud corresponding to the flat region is filtered out from the target tire sidewall point cloud based on the normal difference, and the character point cloud is retained.

[0092] In the specific implementation, in the current embodiment, a filtering algorithm based on the normal difference is performed. The specific algorithm flow is as follows:

[0093] First, take any point P in the target tire sidewall point cloud i , select different radius neighbors r1, r2, and calculate the normal n1, n2 of the point P i .

[0094] Then, according to the angle θ between the two normals n1, n2 of the point P i , filtering is performed, that is, the point Pi whether it belongs to a planar region, and performs filtering.

[0095] Finally, other points are traversed, and the above two steps are repeated, and after the traversal ends, the corresponding character point cloud is obtained.

[0096] Finally, r1 is set to 1.5, r2 is set to 2, and the filtered point cloud is obtained.

[0097] S23: Based on the character point cloud, a character component segmentation is performed through an Euclidean space clustering algorithm.

[0098] Specifically, the Euclidean space clustering algorithm process includes:

[0099] First, a point P in the space is found from the character point cloud i , the nearest n points to P are found, the distances of the n points to P are judged, and points p1, p2, p3,..., whose distances are less than a threshold r, are placed in a set Q. i 22 23 24 .... are found in the set Q, and all of them are placed in the set Q.

[0100] Then, a point p1 in the set Q is found, and the above steps are repeated to find corresponding p

[0101] Finally, when the set Q can no longer have new points added, the search is completed, and each character point cloud is segmented.

[0102] In one or more embodiments of the present application, the determination of the engraving position of the engraved character specifically includes the following steps:

[0103] S31: From each character point cloud segmented, a character region is identified;

[0104] In one embodiment, the number of points can be set to be between 800 and 2000, and the size can be set to be between 5 and 25, so as to complete the search and identification of the character.

[0105] S32: A search and positioning of the engraved character is performed around the character region, wherein the character and the engraved character have a plurality of fixed numbers with a fixed length;

[0106] Specifically, the fixed numbers include factory numbers, specifications, patterns, and brand merchants. It should be noted that the position of the cycle number is the marking position. These fixed numbers all have a fixed length.

[0107] S33: The engraved position of the engraved character is calculated according to the total fixed length of each fixed number and the center and radius of the character. ​​​

[0108] The three-dimensional galvanometer-based tire engraving device, system and method of the present application can effectively avoid the occurrence of operation failure caused by human operation, accurately perform laser engraving on the position of the tire sidewall that needs to be engraved, improve the tire production quality, greatly improve the engraving efficiency of the tire sidewall compared with the two-dimensional laser scanner, and is beneficial to ensuring the consistency of the product. In addition, for the white tire sidewall, the covering glue on the decorative glue sheet can be directly engraved and removed, and the white tire sidewall is exposed, so that the surface of the white glue is fine and smooth.

[0109] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A three-dimensional galvanometer-based tire sculpting system, characterized by: The application relates to a tire carving device and a computer, wherein the tire carving device comprises a casing (1) provided with a laser (2) and a three-dimensional galvanometer (3) in the casing, and the laser (2) is connected with the three-dimensional galvanometer (3) in an optical path; the laser (2) is used for receiving a control command of the computer and initialization, and generating a corresponding laser beam according to the control command and outputting to the three-dimensional galvanometer (3); the three-dimensional galvanometer (3) deflects and controls the received laser beam according to a carving file sent by the computer, so that the laser beam emitted from the three-dimensional galvanometer (3) irradiates to a tire surface and performs carving on the tire surface; the computer is electrically connected with the laser (2) and the three-dimensional galvanometer (3) through a laser control card respectively; the computer analyzes a tire real data model acquired in advance, acquires a relative position relationship between a tire positioning mark coordinate and a pattern needing to be carved, and determines a target tire sidewall carving position based on the relative position relationship; the computer determines a target tire sidewall point cloud based on an initial tire sidewall point cloud acquired in advance, and performs tire character segmentation through flat area filtering processing and a Euclidean space clustering algorithm based on the target tire sidewall point cloud; wherein the flat area filtering processing refers to filtering out point clouds corresponding to flat areas from the target tire sidewall point cloud, and only keeping character point clouds; the computer determines a carving position of a carved character based on character recognition, and generates a carving file containing the carving position according to a character point cloud coordinate and a rotation angle and a shift position of carving content.

2. The three-dimensional galvanometer-based tire engraving apparatus system of claim 1, wherein: The specific implementation of the computer in determining a target tire sidewall point cloud based on an initial tire sidewall point cloud is as follows: a first point set of the initial tire sidewall point cloud is determined, and a target point in the first point set is added to a preset second point set when the target point is determined to be in a range covered by a preset region of interest; after determining that all target points are added, a target tire sidewall point cloud is determined based on the second point set.

3. The three-dimensional galvanometer-based tire engraving apparatus system of claim 1, wherein: The specific implementation of the computer in performing tire character segmentation through flat area filtering processing and a Euclidean space clustering algorithm based on the target tire sidewall point cloud is as follows: point cloud normal estimation is performed based on the target tire sidewall point cloud; character point clouds are obtained by filtering out point clouds corresponding to flat areas from the target tire sidewall point cloud based on normal differences between normal lines of character regions and normal lines of flat areas; character component segmentation is performed based on the character point clouds through a Euclidean space clustering algorithm.

4. The three-dimensional galvanometer-based tire engraving apparatus system of claim 1, wherein: The specific implementation of determining a carving position of a carved character is as follows: a character region is identified from each character point cloud obtained through segmentation; searching and positioning of the carved character are performed around the character region, wherein a plurality of fixed numbers with fixed lengths exist between the character and the carved character; a carving position of the carved character is calculated according to a total fixed length of the fixed numbers, and a center and a radius of the character.

5. The three-dimensional galvanometer-based tire engraving system of claim 4, wherein: The specific implementation of determining the center and the radius of the character is as follows: Perform z value dimension reduction processing based on the target tire sidewall point cloud to obtain a planar point cloud after dimension reduction processing, wherein the planar point cloud has corresponding two-dimensional position information in a pre-established planar rectangular coordinate system; Fit the planar point cloud after dimension reduction processing to obtain a corresponding point cloud curve; Determine the tire radius and tire center based on the two-dimensional position information corresponding to the point cloud curve; Update the z value of the tire center based on the average z value of the character, and take the tire radius and the updated tire center as the center and radius of the character.

6. A three-dimensional galvanometer-based tire sculpting method, characterized in that, Comprise the following steps: Analyze the pre-acquired tire physical data model to obtain the relative position relationship between the tire positioning mark coordinates and the pattern to be engraved, and determine the target tire sidewall engraving position based on the relative position relationship; Determine the target tire sidewall point cloud based on the pre-acquired initial tire sidewall point cloud, and perform tire character segmentation through flat area filtering processing and Euclidean space clustering algorithm based on the target tire sidewall point cloud; wherein the flat area filtering processing refers to filtering out the point cloud corresponding to the flat area from the target tire sidewall point cloud, and only keeping the character point cloud; Determine the engraving position of the engraved character based on character recognition, and generate an engraving file containing the engraving position according to the character point cloud coordinates and the rotation angle and offset position of the engraving content.

7. The three-dimensional galvanometer-based tire engraving method according to claim 6, characterized in that, The determination of the target tire sidewall point cloud based on the pre-acquired initial tire sidewall point cloud comprises the following steps: Determine a first point set of the pre-acquired tire sidewall point cloud, and add a target point in the first point set to a pre-established second point set when it is determined that the target point is within the range covered by a pre-set region of interest; After determining that all target points have been added, determine the target tire sidewall point cloud based on the second point set.

8. The three-dimensional galvanometer-based tire engraving method of claim 6, wherein, The tire character segmentation based on the target tire sidewall point cloud through flat area filtering processing and Euclidean space clustering algorithm comprises the following steps: Perform point cloud normal estimation based on the target tire sidewall point cloud; Filter out the point cloud corresponding to the flat area from the target tire sidewall point cloud based on the normal difference between the normal of the character area and the normal of the flat area to obtain the character point cloud; Perform character component segmentation based on the character point cloud through Euclidean space clustering algorithm.

9. The three-dimensional galvanometer-based tire engraving method of claim 6, wherein, The determination of the engraving position of the engraved character comprises the following steps: Identify the character area from each character point cloud obtained by segmentation; Search and position the engraved character around the character area, wherein there are multiple fixed numbers with fixed lengths between the character and the engraved character; Calculate the engraving position of the engraved character according to the total fixed length of each fixed number and the center and radius of the character.

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