Precision laser welding control method, equipment and system for VCM motors

Abstract

The present invention relates to the field of laser welding technology, and in particular to a precision laser welding control method, device, and system for VCM motors. The method comprises: obtaining edge pixel points in an image of a VCM motor shrapnel to be welded; obtaining an isolation score for each edge pixel point based on the number distribution of edge pixel points in different preset directions of each edge pixel point; using the isolation score to filter the outer frame pixel points; drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, and obtaining the inner frame pixel points based on the position distribution of the edge pixel points on the ray; obtaining the welding path overlap based on the position difference between the welding point and the outer frame pixel points and the inner frame pixel points in multiple consecutive frames of welding images, and adjusting the pulse parameters based on the welding path overlap. The present invention can adaptively control the pulse parameters of laser welding, thereby improving the welding quality of the motor shrapnel.

Description

Technical Field

[0001] The present invention relates to the technical field of laser welding, and in particular to a precision laser welding control method, equipment and system for a VCM motor. Background Art

[0002] Laser welding technology is a type of molten welding that uses a laser beam as energy to impact the weld joint to achieve the purpose of welding. It consists of an optical oscillator and a medium placed between the mirrors at both ends of the oscillator cavity. The main targets of laser welding include the shrapnel of the VCM motor behind the mobile phone lens. The laser welding of such shrapnel mainly includes: (1) obtaining materials; (2) taking pictures; (3) flatness detection; (4) locating the welding point based on the image; (5) laser welding. The main technical implementation process is to control the parameters of laser welding, thereby achieving more precise positioning welding. The process of precision laser welding of mobile phone lenses involves multiple links from material acquisition to laser welding control. The key technical point is the precise control of welding parameters, including laser power, pulse frequency, spot size, focus position, etc. High-precision positioning and real-time parameter adjustment can be achieved through image processing, sensor feedback, and automated control systems to ensure the accuracy and consistency of welding, and ultimately ensure the quality stability of VCM motor shrapnel welding.

[0003] During the welding process of the VCM motor shrapnel, due to the different welding requirements for the inner and outer frames of the shrapnel, if high-frequency pulses or excessively long pulse widths are used in the long outer frame area, excessive heat accumulation will occur, causing over-melting and deformation of the material, or a large heat-affected zone, affecting the structural stability of the shrapnel; when welding the delicate inner frame area, if low-frequency pulses and long pulse widths continue to be used, the welding point may be too large to meet the delicate requirements, and may even cause excessive melting or insufficient welding in complex structures. Summary of the Invention

[0004] In order to solve the problem of poor welding results caused by inappropriate welding parameter settings during the welding of VCM motor springs in existing methods, the purpose of the present invention is to provide a precision laser welding control method, equipment and system for VCM motors. The technical solutions adopted are as follows:

[0005] In a first aspect, the present invention provides a precision laser welding control method for a VCM motor, the method comprising the following steps:

[0006] Obtain edge pixel points in the image of the VCM motor shrapnel to be welded;

[0007] Obtaining an isolation score for each edge pixel based on the number distribution of edge pixels in different preset directions for each edge pixel; using the isolation score to filter outer border pixels; and drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, obtaining inner border pixels based on the position distribution of edge pixels along the ray, wherein the center of the motor shrapnel is determined based on the outer border pixels;

[0008] Obtaining a welding path coincidence degree based on a positional difference between welding points and envelope pixel points in a continuous multi-frame welding image, wherein the continuous multi-frame welding image is an image of the motor shrapnel to be welded captured during the process of welding the motor shrapnel to be welded using a precision laser welding technique, and the envelope pixel points include outer frame pixel points and inner frame pixel points;

[0009] The pulse parameters are adjusted according to the welding path overlap.

[0010] Preferably, obtaining the isolation score of each edge pixel point according to the number distribution of edge pixels in different preset directions of each edge pixel point includes:

[0011] Obtaining a quantity isolation value of the candidate pixel point according to the number of edge pixels in each preset direction of the candidate pixel point, wherein the number of edge pixels in each preset direction of the candidate pixel point is negatively correlated with the quantity isolation value;

[0012] Obtaining an isolation score for the candidate pixel point based on the number of preset directions in which the number of edge pixels in all preset directions of the candidate pixel point is 0 and the numerical isolation value;

[0013] The candidate pixel point is any edge pixel point, and the preset directions include up, down, left and right.

[0014] Preferably, obtaining the isolation score of the candidate pixel point according to the number of preset directions in which the number of edge pixels in all preset directions of the candidate pixel point is 0 and the quantitative isolation value includes:

[0015] Calculate the first sum of the number of edge pixels in all preset directions of the candidate pixel point, which is 0, and the constant 1;

[0016] A normalized result of the product of the number isolation value of the candidate pixel point and the first sum value is determined as the isolation score of the candidate pixel point.

[0017] Preferably, the method of screening outer border pixels by using the isolation score includes:

[0018] Arrange the isolation scores of all edge pixels in descending order to construct an isolation score sequence;

[0019] Calculate the numerical difference between every two adjacent elements in the isolation score sequence; and determine the edge pixel points corresponding to all elements preceding the latter of the two elements corresponding to the largest numerical difference as outer border pixel points.

[0020] Preferably, obtaining the center of the motor shrapnel includes: performing convex hull detection on all outer frame pixel points to obtain the corresponding convex hull area, and taking the center point of the convex hull area as the center of the motor shrapnel.

[0021] Preferably, obtaining inner border pixel points according to the position distribution of edge pixel points on the ray includes:

[0022] Taking the pixel point adjacent to the starting point of the ray as the starting point, the first edge pixel point along each ray is obtained as the inner border pixel point.

[0023] Preferably, obtaining the welding path overlap according to the position difference between the welding point and the envelope pixel point in the continuous multiple-frame welding image includes:

[0024] The outer frame pixel point and the inner frame pixel point closest to the welding point are respectively used as the first reference point and the second reference point;

[0025] The outer welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding first reference point in all welding images; the inner welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding second reference point in all welding images; the welding point is the pixel with the highest infrared value in the welding image;

[0026] The welding path overlap includes the welding outer path overlap and the welding inner path overlap.

[0027] Preferably, the adjusting of pulse parameters according to the welding path overlap comprises:

[0028] If the overlap of the outer welding path is greater than the preset first threshold, short-wave pulse and low-frequency pulse laser are used to continue welding; if the overlap of the outer welding path is less than or equal to the preset first threshold, and the overlap of the inner welding path is greater than the preset first threshold, short-wave pulse width and high-frequency pulse laser are used to continue welding; otherwise, welding is continued using the welding pulse parameters of the inner frame line.

[0029] In a second aspect, the present invention provides a precision laser welding control device for a VCM motor, comprising a memory and a processor, wherein the processor executes a computer program stored in the memory to implement a precision laser welding control method for the VCM motor.

[0030] In a third aspect, the present invention further provides a precision laser welding control system for a VCM motor, the system comprising:

[0031] An image acquisition module is used to obtain edge pixel points in multiple frames of monitoring images of the VCM motor shrapnel to be welded;

[0032] a screening module for obtaining an isolation score for each edge pixel based on the number of edge pixels in different preset directions of each edge pixel; using the isolation score to screen outer border pixels; and drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, and obtaining inner border pixels based on the position distribution of the edge pixels on the rays, wherein the center of the motor shrapnel is determined based on the outer border pixels;

[0033] a calculation module for obtaining a welding path coincidence degree based on a position difference between a welding point and envelope pixels in a plurality of consecutive welding image frames, wherein the plurality of consecutive welding image frames are images of the motor shrapnel to be welded acquired during the process of welding the motor shrapnel to be welded using a precision laser welding technique, and the envelope pixels include outer frame pixels and inner frame pixels;

[0034] A control module is used to adjust pulse parameters according to the welding path overlap.

[0035] The present invention has at least the following beneficial effects:

[0036] The present invention first obtains the edge pixel points in the image of the VCM motor shrapnel to be welded, and then combines the structural features of the inner and outer frame lines of the VCM motor shrapnel to be welded to identify the outer and inner frame pixels from all edge pixels, collects multiple frames of welding images during the welding process of the VCM motor shrapnel to be welded, and evaluates the welding path overlap based on the position difference between the welding point and the envelope pixel points in the collected multiple frames of welding images, that is, the specific position of the welding is judged, and the corresponding welding pulse parameters are assigned based on the judgment result. The method provided by the present invention eliminates the problems of reduced welding accuracy and quality caused by the thermal effect of welding by adaptively controlling the pulse parameters of laser welding, thereby improving the welding quality of the motor shrapnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 A flowchart of a precision laser welding control method for a VCM motor provided by an embodiment of the present invention;

[0039] Figure 2 This is a graph showing the edge detection results provided by an embodiment of the present invention;

[0040] Figure 3 This is a structural block diagram of a precision laser welding control system for a VCM motor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the precision laser welding control method, equipment and system for VCM motors proposed in accordance with the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0042] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0043] The specific solutions of the precision laser welding control method, device and system for VCM motors provided by the present invention are described in detail below with reference to the accompanying drawings.

[0044] Precision laser welding control method embodiment for VCM motor:

[0045] The specific scenario targeted by this embodiment is: in the process of laser welding of VCM motor shrapnel, in order to ensure the welding quality, an image of the VCM motor shrapnel is obtained, edge detection is performed on it using the Canny operator, the structural characteristics of the motor shrapnel are analyzed, and the envelope results of the inner and outer frames of the motor are obtained; the welding results are analyzed in combination with the welding sequence under different frames, and the pulse parameters in the subsequent welding process are adjusted based on the current welding results.

[0046] This embodiment proposes a precision laser welding control method for VCM motors, such as Figure 1 As shown, the precision laser welding control method for a VCM motor of this embodiment includes the following steps:

[0047] Step S1, obtaining edge pixel points in an image of a VCM motor shrapnel to be welded.

[0048] First, secure the VCM motor shrapnel to be welded to the welding platform using a clamp or vacuum suction to ensure that the material does not move during the welding process. Positioning accuracy should be ±0.01 mm, and adequate securing force should be used to prevent deformation. An industrial camera should be installed and aimed at the VCM motor shrapnel to be welded. Ensure that the lighting system (such as a ring light or laser auxiliary light source) evenly covers the surface of the VCM motor shrapnel to be welded to reduce reflections and shadows. Set the resolution to 2000x2000 pixels or higher, the frame rate to 30fps, and the exposure time to 100µs to 1ms (adjustable based on ambient light). Capture an RGB image of the VCM motor shrapnel to be welded and transfer it to a computer or PLC system for processing. The captured RGB image of the VCM motor shrapnel to be welded is grayscaled and recorded as the image of the VCM motor shrapnel to be welded. Image grayscale processing is conventional technology and will not be further described here.

[0049] The Canny algorithm is a standard algorithm widely used for edge detection. Its goal is to find an optimal edge detection solution, or the location within an image where the grayscale intensity changes most strongly. Optimal edge detection is primarily evaluated based on three criteria: low error rate, high localization, and minimum response. The Canny algorithm was used to detect edges in an image of a VCM motor shrapnel to be welded. Due to the low distinction between the target and background in the original image, the edge detection stage required high and low threshold control. The low threshold was set to 0.12, and the high threshold was set to 0.16. This was used to extract edge pixels from the image of the VCM motor shrapnel to be welded. The Canny algorithm is an existing technology and will not be further elaborated here. In specific applications, implementers can set thresholds based on specific circumstances.

[0050] At this point, this embodiment has acquired all edge pixel points in the image of the VCM motor shrapnel to be welded.

[0051] Step S2, obtaining the isolation score of each edge pixel point according to the number distribution of edge pixels in different preset directions of each edge pixel point; using the isolation score to filter the outer border pixel points; drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, and obtaining the inner border pixel points according to the position distribution of the edge pixel points on the ray, wherein the center of the motor shrapnel is determined based on the outer border pixel points.

[0052] The structure of the VCM motor shrapnel is relatively regular and is mainly divided into the outer frame line to be welded, the inner frame line, and the included fill line. The outer frame line is in a rectangular shape and appears as a relatively regular geometric body in the image; the inner frame line is in an elliptical or circular shape, and is relatively simple and regular as a whole. Due to the special structure of the VCM motor shrapnel, the welding parameters and requirements of the inner and outer frame lines are different during the welding process. Using the same laser pulse welding parameters will cause melting, insufficient welding, etc. In order to solve this problem, the pulse parameters are adapted, and the adaptive logic is mainly to detect the inner and outer frame lines through real-time image analysis, and identify them in combination with the structural characteristics of the shrapnel frame line to obtain the envelope result of the inner and outer frames, that is, to identify the structure of the specific shrapnel. In order to accurately assign the corresponding welding pulse parameters, it is necessary to combine the welding path and welding sequence to perform predictive analysis of the pulse parameters, and then realize the configuration of parameters such as the pulse frequency accurately and on time.

[0053] In step S1, this embodiment performs edge detection on the image of the VCM motor shrapnel to be welded, and obtains a plurality of edge pixel points, such as Figure 2 As shown in the figure, the part with a grayscale value of 1 is the edge pixel point of the VCM motor shrapnel to be welded, and the part with a grayscale value of 0 is the background part and the non-edge part on the VCM motor shrapnel to be welded.

[0054] In order to assign accurate welding pulse parameters, it is necessary to identify the specific position distribution of edge pixel points, that is, whether the edge pixel point is a point on the outer frame edge line of the motor shrapnel or a point on the inner frame edge line, and then adjust the corresponding pulse parameters according to different needs.

[0055] When the edge pixel point is a point on the outer frame line, since there are no other pixel points around it for auxiliary identification and only a certain background exists, its isolation is higher, and it can better represent the outermost part of the motor shrapnel to be welded. For the outer frame line part, since it is usually longer and the precision requirements are relatively low, it does not require extremely high welding details, but requires fast welding speed and sufficient welding strength; when welding the outer frame, a shorter pulse and lower frequency pulse laser can be used. This method reduces heat accumulation and ensures that the outer frame welding area will not produce a large heat-affected zone or material deformation due to excessive heat input, while improving welding efficiency. Based on the above characteristics, the regional isolation of the edge pixel points is analyzed next, and the inner and outer frame lines are identified in combination with the structural characteristics of the frame.

[0056] This embodiment is described by taking one edge pixel point as an example, and other edge pixels can be processed using the method provided in this embodiment.

[0057] Specifically, any edge pixel point is recorded as a candidate pixel point, and a quantitative isolation value of the candidate pixel point is obtained according to the number of edge pixels in each preset direction of the candidate pixel point, and the number of edge pixels in each preset direction of the candidate pixel point is negatively correlated with the quantitative isolation value.

[0058] In this embodiment, there are four preset directions, namely upward, downward, left and right.

[0059] Among them, the negative correlation relationship means that the dependent variable will decrease as the independent variable increases, and the dependent variable will increase as the independent variable decreases. It can be a subtraction relationship, a division relationship, etc., which is determined by actual application.

[0060] In this embodiment, a specific calculation formula for the number of isolated values ​​is given. The number of isolated values ​​of the u-th edge pixel can be expressed as:

[0061]

[0062] in, Indicates the number of isolated values ​​of the u-th edge pixel, Indicates the number of preset directions, Indicates the number of edge pixels in the i-th preset direction of the u-th edge pixel, Indicates the preset first adjustment parameter.

[0063] This embodiment introduces a preset first adjustment parameter into the calculation formula for the number of isolated pixels to prevent the denominator from being zero. In this embodiment, the preset value of the first adjustment parameter is 0.01. In specific applications, the implementer can set this parameter based on specific circumstances. The fewer edge pixels in each preset direction of the u-th edge pixel, the lower the magnitude of the border of the u-th edge pixel in all preset directions. In this case, the corresponding isolation is higher, and the more likely it is to be part of the outer border of the motor shrapnel. In other words, the number of isolated pixels of the u-th edge pixel is larger.

[0064] Furthermore, when edge pixels are located in the outer border, due to spatial constraints, there must be a preset direction where the number of edge pixels is zero. Therefore, this feature is added to the isolation determination to obtain an isolation score. For a candidate pixel, the first sum of the number of preset directions in which the number of edge pixels in all preset directions of the candidate pixel is zero and a constant of 1 is calculated; the normalized product of the candidate pixel's number of isolated pixels and the first sum is determined as the candidate pixel's isolation score.

[0065] In this embodiment, a specific calculation formula for the isolation score is given. The isolation score of the u-th edge pixel point can be expressed as:

[0066]

[0067] in, represents the isolation score of the u-th edge pixel, Indicates the number of isolated values ​​of the u-th edge pixel, represents the number of preset directions in which the number of edge pixels in all preset directions of the u-th edge pixel is 0, norm() represents the linear normalization function, Represents the first sum value.

[0068] When the number of preset directions in which the number of edge pixels in all preset directions of the u-th edge pixel point is 0 is greater and the number isolation value of the u-th edge pixel point is greater, it is closer to the distribution pattern of the outer border pixels, that is, the isolation score of the u-th edge pixel point is greater.

[0069] By adopting the above method, the isolation score of each edge pixel point can be obtained, and the isolation scores of all edge pixel points are arranged in order from large to small to obtain an isolation score sequence; the numerical difference between every two adjacent elements in the isolation score sequence is calculated; the edge pixel points corresponding to all elements before the latter element of the two elements corresponding to the largest numerical difference are determined as outer border pixel points, that is, multiple outer border pixel points are screened out from all edge pixel points.

[0070] In this embodiment, multiple outer frame pixels are screened in the above steps. Then, convex hull detection is performed on all outer frame pixels to obtain the corresponding convex hull area, and the center point of the convex hull area is used as the center of the motor spring. Convex hull detection is a prior art and will not be described in detail here.

[0071] Then, multiple rays are drawn with the center of the motor shrapnel as the starting point. The starting points of these rays are the same, that is, the center of the motor shrapnel. In this embodiment, the angle between each two adjacent rays is set to 3°, that is, multiple rays in different directions are obtained.

[0072] For any ray: Take the pixel point adjacent to the starting point of the ray as the starting point, and obtain the first edge pixel along the ray as the inner border pixel point. Use the above method to process each ray to obtain multiple inner border pixels.

[0073] Step S3, obtaining the welding path overlap based on the position difference between the welding point and the envelope pixel point in the continuous multi-frame welding image, wherein the continuous multi-frame welding image is an image of the motor shrapnel collected during the process of welding the VCM motor shrapnel to be welded using precision laser welding technology, and the envelope pixel point includes the outer frame pixel point and the inner frame pixel point.

[0074] To evaluate the current welding results and achieve adaptive adjustment of welding parameters, it is necessary to analyze welding images from different frames. Therefore, it is necessary to analyze welding results at different times to obtain the final predicted configuration. Therefore, this embodiment captures multiple frames of welding images of the VCM motor shrapnel to be welded within the current time period. The current time period is the set of all historical moments whose time interval with the current moment is less than or equal to a preset duration. It should be noted that the current time period is the time period during which the VCM motor shrapnel to be welded is welded using precision laser welding technology. In this embodiment, the preset duration is 2 minutes. In specific applications, the implementer can set the preset duration and welding image acquisition frequency based on specific circumstances. Thus, multiple consecutive frames of welding images of the VCM motor shrapnel welding process have been captured. It should be noted that all welding images captured in this embodiment are of the same size as the image of the VCM motor shrapnel to be welded captured in step S1. That is, the field of view and position of the image acquisition device remain fixed during the capture of all images.

[0075] For any welding image frame, the infrared value of each pixel in the welding image is obtained. The pixel with the largest infrared value is used as the welding point. The outer frame pixel closest to the welding point is used as the first reference point, and the inner frame pixel closest to the welding point is used as the second reference point. It should be noted that if there is more than one pixel with the largest infrared value in a welding image frame, the pixel in the welding image that is located at the same position as the center of the motor shrapnel in the image of the VCM motor shrapnel to be welded is used as the mapping point of the motor shrapnel center. The pixel with the largest infrared value closest to the mapping point of the motor shrapnel center is used as the welding point. Using this method, the welding point in each welding image frame and the first and second reference points corresponding to the welding point in each welding image frame can be obtained.

[0076] The external welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding first reference point in all welding images; the internal welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding second reference point in all welding images; the welding point is the pixel point with the highest infrared value in the welding image; the welding path coincidence includes the external welding path coincidence and the internal welding path coincidence.

[0077] In this embodiment, specific calculation formulas for the overlap of the outer welding path and the overlap of the inner welding path are given. The overlap of the outer welding path and the overlap of the inner welding path can be expressed as follows:

[0078]

[0079]

[0080] in, Indicates the overlap of the welding external path, represents the path overlap within the weld, U represents the number of weld images, represents the difference in the horizontal coordinates between the welding point in the u-th welding image and the corresponding first reference point, represents the difference in ordinate between the welding point in the u-th welding image and the corresponding first reference point, represents the difference in the horizontal coordinates between the welding point in the u-th frame welding image and the corresponding second reference point, represents the difference in ordinate between the welding point in the u-th frame welding image and the corresponding second reference point, Indicates the absolute value sign.

[0081] It should be noted that: in this embodiment, the difference in the horizontal coordinates and the difference in the vertical coordinates are both represented by the absolute values ​​of the differences between the corresponding coordinates.

[0082] The constant 1 is added to the denominator in the calculation formulas of the welding external path overlap and the welding internal path overlap in order to prevent the denominator from being zero. It is used to represent the coordinate difference between the welding point in the u-th frame welding image and the corresponding first reference point. The larger the value, the greater the coordinate difference between the two points and the farther the distance between the two points. It is used to represent the coordinate difference between the welding point in the u-th frame welding image and the corresponding second reference point. The larger the value, the greater the coordinate difference between the two points and the farther the distance between the two points.

[0083] So far, the welding path coincidence is obtained by using the above method, wherein the welding path coincidence includes the welding outer path coincidence and the welding inner path coincidence.

[0084] Step S4: adjusting pulse parameters according to the welding path overlap.

[0085] In this embodiment, the outer welding path overlap and the inner welding path overlap are obtained in the above steps. Next, the pulse parameters will be adjusted based on the outer welding path overlap and the inner welding path overlap.

[0086] Specifically, if the overlap of the outer weld paths exceeds a preset first threshold, welding continues using a short-wavelength pulsed laser with a low frequency (lowest setting). This approach reduces heat accumulation, ensuring that the outer frame weld area does not experience a large heat-affected zone or material deformation due to excessive heat input, while also improving welding efficiency. If the overlap of the outer weld paths is less than or equal to the preset first threshold, and the overlap of the inner weld paths is greater than the preset first threshold, welding continues using a short-wavelength pulsed laser with a high frequency (highest setting), resulting in a more precise weld, a smaller weld point, and a more concentrated and controllable heat-affected zone. Otherwise, welding continues using the inner frame line's welding pulse parameters. In this embodiment, the preset first threshold is 0.95; in specific applications, the implementer can set this threshold based on specific circumstances.

[0087] Thus, the method provided in this embodiment has been used to complete the adaptive adjustment of the pulse parameters in the laser welding process.

[0088] This embodiment first obtains the edge pixel points in the image of the VCM motor shrapnel to be welded, and then combines the structural features of the inner and outer frame lines of the VCM motor shrapnel to be welded to identify the outer and inner frame pixels from all edge pixels, collects multiple frames of welding images during the welding process of the VCM motor shrapnel to be welded, and evaluates the welding path overlap based on the position difference between the welding point and the envelope pixel points in the collected multiple frames of welding images, that is, the specific position of the welding is judged, and the corresponding welding pulse parameters are assigned based on the judgment result. The method provided in this embodiment eliminates the problems of reduced welding accuracy and quality caused by the thermal effect of welding by adapting the pulse parameters of laser welding, thereby improving the welding quality of the motor shrapnel.

[0089] Precision laser welding control equipment for VCM motors:

[0090] A precision laser welding control device for a VCM motor in this embodiment includes a memory and a processor. The processor executes a computer program stored in the memory to implement the precision laser welding control method for a VCM motor described above.

[0091] Precision laser welding control system example for VCM motors:

[0092] like Figure 3 As shown in the figure, the structure block diagram of the precision laser welding control system for VCM motor is shown, and the system includes an image acquisition module, a screening module, a calculation module and a control module;

[0093] Among them, the image acquisition module is used to obtain edge pixel points in multiple frames of monitoring images of the VCM motor shrapnel to be welded;

[0094] a screening module for obtaining an isolation score for each edge pixel based on the number of edge pixels in different preset directions of each edge pixel; using the isolation score to screen outer border pixels; and drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, and obtaining inner border pixels based on the position distribution of the edge pixels on the rays, wherein the center of the motor shrapnel is determined based on the outer border pixels;

[0095] a calculation module for obtaining a welding path coincidence degree based on a position difference between a welding point and envelope pixels in a plurality of consecutive welding image frames, wherein the plurality of consecutive welding image frames are images of the motor shrapnel to be welded acquired during the process of welding the motor shrapnel to be welded using a precision laser welding technique, and the envelope pixels include outer frame pixels and inner frame pixels;

[0096] A control module is used to adjust pulse parameters according to the welding path overlap.

[0097] It should be understood that Figure 3 The block diagram of a precision laser welding control system for VCM motors and its modules can be implemented in various ways. For example, in some embodiments, the system and its modules can be implemented using hardware, software, or a combination of software and hardware. The hardware portion can be implemented using dedicated logic, while the software portion can be stored in memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated hardware. Those skilled in the art will appreciate that the above-described methods and systems can be implemented using computer-executable instructions and / or contained in processor control code, for example, provided on a carrier medium such as a disk, CD, or DVD-ROM, a programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The systems and their modules described herein can be implemented not only using hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips or transistors, or programmable hardware devices such as field-programmable gate arrays or programmable logic devices, but can also be implemented using software executed by various types of processors, or a combination of such hardware circuits and software (e.g., firmware).

[0098] For more details about the above modules, please refer to other places in this manual and will not be repeated here.

[0099] In other embodiments, a medium is also provided, which stores at least one program executable by a computer. When the at least one program is executed by a computer, the computer executes the steps of the precision laser welding control method for VCM motors in the above embodiment. The medium can be a computer-readable storage medium.

[0100] Among them, the provided equipment, system, and medium are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0101] It should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A precision laser welding control method for VCM motor, characterized in that: The method comprises the following steps: Obtain edge pixel points in the image of the VCM motor shrapnel to be welded; Obtaining an isolation score for each edge pixel based on the number distribution of edge pixels in different preset directions for each edge pixel; using the isolation score to filter outer border pixels; and drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, obtaining inner border pixels based on the position distribution of edge pixels along the ray, wherein the center of the motor shrapnel is determined based on the outer border pixels; Obtaining a welding path coincidence degree based on a positional difference between welding points and envelope pixel points in a continuous multi-frame welding image, wherein the continuous multi-frame welding image is an image of the motor shrapnel to be welded captured during the process of welding the motor shrapnel to be welded using a precision laser welding technique, and the envelope pixel points include outer frame pixel points and inner frame pixel points; The pulse parameters are adjusted according to the welding path overlap.

2. The precision laser welding control method for VCM motor according to claim 1, characterized in that: Obtaining the isolation score of each edge pixel point according to the number distribution of edge pixels in different preset directions of each edge pixel point includes: Obtaining a quantity isolation value of the candidate pixel point according to the number of edge pixels in each preset direction of the candidate pixel point, wherein the number of edge pixels in each preset direction of the candidate pixel point is negatively correlated with the quantity isolation value; Obtaining an isolation score for the candidate pixel point based on the number of preset directions in which the number of edge pixels in all preset directions of the candidate pixel point is 0 and the numerical isolation value; The candidate pixel point is any edge pixel point, and the preset directions include up, down, left and right.

3. The precision laser welding control method for VCM motor according to claim 2, characterized in that: Obtaining the isolation score of the candidate pixel point according to the number of preset directions in which the number of edge pixels in all preset directions of the candidate pixel point is 0 and the quantitative isolation value includes: Calculate the first sum of the number of edge pixels in all preset directions of the candidate pixel point, which is 0, and the constant 1; A normalized result of the product of the number isolation value of the candidate pixel point and the first sum value is determined as the isolation score of the candidate pixel point.

4. The precision laser welding control method for VCM motor according to claim 1, characterized in that: The method of screening outer border pixels using the isolation score includes: Arrange the isolation scores of all edge pixels in descending order to construct an isolation score sequence; Calculate the numerical difference between every two adjacent elements in the isolation score sequence; and determine the edge pixel points corresponding to all elements preceding the latter of the two elements corresponding to the largest numerical difference as outer border pixel points.

5. The precision laser welding control method for VCM motor according to claim 1, characterized in that: The acquisition of the center of the motor shrapnel includes: performing convex hull detection on all outer frame pixel points to obtain a corresponding convex hull area, and taking the center point of the convex hull area as the center of the motor shrapnel.

6. The precision laser welding control method for VCM motor according to claim 1, characterized in that: The step of obtaining inner border pixel points according to the position distribution of edge pixel points on the ray includes: Taking the pixel point adjacent to the starting point of the ray as the starting point, the first edge pixel point along each ray is obtained as the inner border pixel point.

7. The precision laser welding control method for VCM motor according to claim 1, characterized in that: The method of obtaining the welding path coincidence degree according to the position difference between the welding point and the envelope pixel point in the continuous multiple-frame welding image includes: The outer frame pixel point and the inner frame pixel point closest to the welding point are respectively used as the first reference point and the second reference point; The outer welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding first reference point in all welding images; the inner welding path coincidence is obtained based on the coordinate difference between the welding point and the corresponding second reference point in all welding images; the welding point is the pixel with the highest infrared value in the welding image; The welding path overlap includes the welding outer path overlap and the welding inner path overlap.

8. The precision laser welding control method for a VCM motor according to claim 7, characterized in that: The adjusting of pulse parameters according to the welding path overlap comprises: If the overlap of the outer welding path is greater than the preset first threshold, short-wave pulse and low-frequency pulse laser are used to continue welding; if the overlap of the outer welding path is less than or equal to the preset first threshold, and the overlap of the inner welding path is greater than the preset first threshold, short-wave pulse width and high-frequency pulse laser are used to continue welding; otherwise, welding is continued using the welding pulse parameters of the inner frame line.

9. A precision laser welding control device for a VCM motor, comprising a memory and a processor, characterized in that: The processor executes the computer program stored in the memory to implement the precision laser welding control method for a VCM motor according to any one of claims 1 to 8.

10. A precision laser welding control system for VCM motors, characterized in that: The system comprises: An image acquisition module is used to obtain edge pixel points in multiple frames of monitoring images of the VCM motor shrapnel to be welded; a screening module for obtaining an isolation score for each edge pixel based on the distribution of the number of edge pixels in different preset directions of each edge pixel; using the isolation score to screen outer border pixels; and drawing rays in several directions with the center of the motor shrapnel as the starting point of the ray, and obtaining inner border pixels based on the position distribution of the edge pixels on the rays, wherein the center of the motor shrapnel is determined based on the outer border pixels; a calculation module for obtaining a welding path coincidence degree based on a position difference between a welding point and envelope pixels in a plurality of consecutive welding image frames, wherein the plurality of consecutive welding image frames are images of the motor shrapnel to be welded acquired during the process of welding the motor shrapnel to be welded using a precision laser welding technique, and the envelope pixels include outer frame pixels and inner frame pixels; A control module is used to adjust pulse parameters according to the welding path overlap.

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