Laser processing method and system based on Bezier curve surface mapping

Abstract

The invention relates to the technical field of laser processing, in particular to a laser processing method and system based on Bezier curve surface mapping. According to the scheme, the complex curved surface A1 of the to-be-machined area is mapped into the Bessel curved surface based on Bessel curve curved surface mapping, high-energy focusing light spots for laser machining are guided to achieve machining path planning and self-adaptive laser machining operation of various complex curved surface types on the complex curved surface A1 in the three-dimensional space, and the automation maintenance operation degree is improved; the quality consistency after maintenance is ensured; meanwhile, coordinates of a moving point P of a laser focusing light spot and a tangential track of the moving point P are calculated in real time based on a Bezier curve surface mapping method, and the laser machining head is controlled to conduct self-adaptive adjustment of the attitude angle along the tangential track. And it is guaranteed that focusing light spots formed by high-energy laser beam irradiation during laser processing work cannot be defocused due to the problem of the incident angle of the laser beam, energy intensity changes are caused, and the laser processing quality is not affected.

Description

Technical Field

[0001] The invention relates to the field of laser processing technology, in particular to a laser processing method and system based on Bezier curve and surface mapping. Background Art

[0002] In order to ensure the utilization rate of water energy, most of the important working parts of hydroelectric generating units are designed with irregular complex curved surfaces based on fluid mechanics. Once defects or damage occur after long-term service and need to be repaired (such as local scratches, cavitation, crack repair welding and laser cladding strengthening treatment, cutting and repair welding of surface edge defects and other maintenance scenarios), their various irregular complex curved surfaces are extremely difficult to repair within the limited maintenance period compared with semi-automatic or automated maintenance operations. Often, they can only be repaired in different areas by manual + tool methods, which is extremely labor-intensive. In addition, manual repair is limited by skill level and has the problem of poor consistency in maintenance quality.

[0003] Therefore, there is a need for a processing method and system that can realize adaptive trajectory planning and posture adjustment for irregular and complex surfaces of various workpieces, achieve a high degree of automated maintenance operations, and ensure the quality consistency of workpieces after maintenance. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to solve non-standard maintenance scenarios such as local scratches, cavitation, cracks, surface edge defects, etc. for various workpieces with irregular and complex surface shapes, and realize the processing problem of adaptive trajectory planning and posture adjustment.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: obtaining the area A1 to be processed by a three-dimensional measurement camera, wherein A1 represents a complex curved surface, collecting the cloud data information and profile feature information of the points of A1, and constructing the curved surface line type;

[0007] By analyzing and extracting the parameters of the surface line type, the parameters of the surface line type are substituted into the data processing module to obtain the surface information of laser processing;

[0008] By calibrating the linear laser of the line laser device, it is ensured that the linear laser is correctly irradiated on the area to be processed A1, and a moving point P is obtained, wherein the moving point P represents a moving point in the focused light spot;

[0009] Take the moving point P as the center point and extend to both sides to output the trajectory planning for subsequent processing;

[0010] Set the laser processing parameters in the control system, map the parameters of the surface line type according to the data processing module combined with the Bezier curve theory, and define the motion trajectory of the laser processing head;

[0011] According to the tangential trajectory of the moving point P calculated in real time by the data processing module, the control system controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations;

[0012] By monitoring the tangential trajectory and coordinates of the moving point P during laser processing, the processing process is ensured to be correct. After the processing is completed, the processing quality is checked and evaluated.

[0013] In the first aspect, an embodiment of the present invention provides a laser processing method based on Bezier curve surface mapping, which includes: performing parameter mapping on the parameters of the surface line type according to the data processing module in combination with the Bezier curve theory, mapping A1 to a Bezier surface, using the laser focused light spot as an arbitrary moving point P on the Bezier surface, calculating the coordinates in real time in combination with the coordinate calculation method of any moving point P (u, v) on the Bezier surface, synchronously and in real time derivatizing the coordinates of the moving point P (u, v) of the focused light spot, obtaining the tangential trajectory of the moving point P of the focused light spot, and feeding back the calculation results to the control system.

[0014] As a preferred solution of the laser processing method based on Bezier curve surface mapping of the present invention, wherein: by parsing and extracting the parameters of the surface line type, the surface feature information of the surface is parsed and the surface line type parameters are extracted, and a unique Bezier curve is obtained according to the tangent of the start and end points and control points of the multi-order Bezier curve and the surface line type parameters of the complex surface are defined, and the surface trajectory of the measured area A1 to be processed is constructed using the following formula:

[0015]

[0016] Where n represents the n-order Bezier curve; P i,j Indicates the position of the jth vertex corresponding to the i-th n-order Bezier curve; B n j Represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the j-th vertex position, u represents the control point corresponding to the j-th position, and any control point P(u) on the i-th n-th order Bezier curve is a linear combination of the vertices on the corresponding curve; P(u,v) represents the coordinates of the point at the v position on the area A1 to be processed corresponding to the movement adjustment of the control point u corresponding to the j-th position on the curve.

[0017] As a preferred solution of the laser processing method based on Bezier curve surface mapping of the present invention, wherein: the measured area A1 to be processed is divided into m equal parts of surface line types L1, L2, ..., L formed by n-order Bezier curves.m , any Bezier curve is composed of n+1 points forming n line segments, resulting in (n+1)*m vertices. The complex surface is divided into m equal parts. The surface line type composed of n-order Bezier curves can obtain m P(u), recorded as P(u)0, P(u)1...P(u) m , where the Bezier curve corresponds to the point P(v) on the Bezier surface using the following formula:

[0018]

[0019] Where m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed.

[0020] As a preferred solution of the laser processing method based on Bezier curve surface mapping described in the present invention, wherein: the parameters of the surface line type are mapped according to the data processing module in combination with the Bezier curve theory, A1 is mapped to a Bezier surface, the laser focus point is used as an arbitrary moving point P on the Bezier surface, and the coordinates are calculated in real time in combination with the coordinate calculation method of an arbitrary moving point P (u, v) on the Bezier surface. The coordinate calculation of an arbitrary moving point P (u, v) on the Bezier surface adopts the following formula:

[0021]

[0022] Where m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed; n represents the n-order Bezier curve; P i,j represents the j-th vertex position of the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, and P(u,v) represents the coordinates of the point at the v-th position on the processing area A1 adjusted by the movement of the control point u corresponding to the j-th position on the curve.

[0023] As a preferred solution of the laser processing method based on Bezier curve and surface mapping of the present invention, the matrix for the coordinate calculation of P(u,v) adopts the following formula:

[0024]

[0025] Among them, B n 0(u) represents the Bernstein polynomial corresponding to the nth-order Bezier curve passing through the first vertex position, B n 1(u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the second vertex position, B nn (u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the n+1th vertex position; m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed; n represents the n-order Bezier curve; P i,j represents the j-th vertex position corresponding to the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, P(u,v) represents the coordinates of the point at the v-th position on the area A1 to be processed adjusted by the movement of the control point u corresponding to the j-th position on the curve; v represents the position on the area A1 to be processed.

[0026] As a preferred solution of the laser processing method based on Bezier curve surface mapping of the present invention, wherein: the tangential trajectory of the arbitrary point P on the surface can be obtained by derivation based on the coordinates of an arbitrary point P (u, v) on the area to be processed A1, and the derivation calculation adopts the following formula:

[0027]

[0028] Among them, dP(u,v) represents the direction of the tangent trajectory through any point P(u,v) on the surface A1 to be processed, dP(u,v) represents the tangent line through any point P(u,v) on the area A1 (surface) to be processed, and d(u,v) represents the derivative of the motion of the control points u and v along the surface A1.

[0029] In a second aspect, an embodiment of the present invention provides a laser processing system based on Bezier curve and surface mapping, which includes:

[0030] A construction module obtains the area A1 to be processed through a three-dimensional measurement camera, wherein A1 represents a complex surface, collects the cloud data information and surface feature information of the points of A1, and constructs the surface line type;

[0031] The parsing module parses and extracts the parameters of the surface line type, and substitutes the parameters of the surface line type into the data processing module to obtain the surface information of the laser processing;

[0032] A calibration module, which ensures that the linear laser is correctly irradiated on the area to be processed A1 by calibrating the linear laser of the line laser device, and obtains a moving point P, wherein the moving point P represents a moving point in the focused light spot;

[0033] The output module outputs the trajectory planning for subsequent processing based on extending to both sides with the moving point P as the center point;

[0034] A mapping module sets the laser processing parameters in the control system, performs parameter mapping on the surface line type parameters according to the data processing module combined with the Bezier curve theory, and defines the motion trajectory of the laser processing head;

[0035] The adjustment module controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations according to the tangential trajectory of the moving point P calculated in real time by the data processing module;

[0036] The evaluation module ensures the correctness of the processing by monitoring the tangential trajectory and coordinates of the moving point P during the laser processing. After the processing is completed, the processing quality is checked and evaluated.

[0037] In a third aspect, an embodiment of the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the laser processing method based on Bezier curve and surface mapping as described in the first aspect of the present invention are implemented.

[0038] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the laser processing method based on Bezier curve and surface mapping as described in the first aspect of the present invention are implemented.

[0039] The beneficial effects of the present invention are as follows: the present invention maps the complex surface A1 of the area to be processed into the Bezier surface based on Bezier curve surface mapping, guides the high-energy focused light spot of laser processing to realize processing trajectory planning and adaptive laser processing operations for various complex surface types on the complex surface A1 in three-dimensional space, improves the degree of automated maintenance operations, and ensures the consistency of quality after maintenance; at the same time, the present invention calculates the coordinates of the moving point P of the laser focused light spot and the tangential trajectory of the moving point P in real time based on the Bezier curve surface mapping method, controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory, and ensures that the focused light spot formed by the irradiation of the high-energy laser beam during the laser processing operation will not be defocused due to the problem of the incident angle of the laser beam, resulting in changes in energy intensity that affect the laser processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0041] Figure 1 It is a flow chart of a laser processing method based on Bezier curve surface mapping;

[0042] Figure 2 A computer device diagram for a laser processing method based on Bezier curve surface mapping;

[0043] Figure 3 It is a schematic diagram of Bezier curve surface parameter mapping for a complex surface A1 in a laser processing method based on Bezier curve surface mapping;

[0044] Figure 4 Schematic diagram of the laser processing method based on Bezier curve surface mapping. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0046] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0047] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0048] Example 1

[0049] Reference Figure 1 to Figure 4 , which is the first embodiment of the present invention, provides a laser processing method based on Bezier curve surface mapping, comprising:

[0050] S1: The area A1 to be processed is obtained through a 3D measurement camera. A1 represents a complex surface. The cloud data information and surface feature information of A1 are collected, and the surface line type is constructed.

[0051] A 3D measuring camera is installed to measure the area to be processed (complex surface) A1, and the point cloud data and surface feature information of A1 are collected. The surface line parameters are extracted and analyzed synchronously and fed back to the data processing module.

[0052] S2: By parsing and extracting the parameters of the surface line type, the parameters of the surface line type are substituted into the data processing module to obtain the surface information of laser processing;

[0053] S3: by calibrating the linear laser of the line laser device, ensuring the correct irradiation of the linear laser on the area to be processed A1, and obtaining a moving point P, where the moving point P represents a moving point in the focused light spot;

[0054] S4: Extend to both sides with the moving point P as the center point and output the trajectory planning for subsequent processing;

[0055] Turn on the laser processing device and the line laser device, calibrate the linear laser emitted by the line laser device to irradiate the surface A1 of the area to be processed (complex curved surface), and extend it to both sides with the moving point P of the focused light spot as the center point. Through the control system and the motion mechanism programming and teaching, the laser processing trajectory planning of the moving point P of the focused light spot can cover the area to be processed (complex curved surface) A1, and simultaneously set the process parameters of the laser processing operation in the control system.

[0056] S5: setting laser processing parameters in the control system, performing parameter mapping on the surface line type parameters according to the data processing module combined with Bezier curve theory, and defining the motion trajectory of the laser processing head;

[0057] In the data processing module, the surface line parameters extracted from the complex surface A1 are parameter mapped by combining the theoretical methods of Bezier curves and surfaces, and the complex surface A1 is mapped to a Bezier surface. The laser focused light spot is used as an arbitrary moving point P on the Bezier surface. The coordinates are calculated in real time by combining the coordinate calculation method of an arbitrary moving point P (u, v) on the Bezier surface. The coordinates of the moving point P (u, v) of the focused light spot are derived synchronously and in real time to obtain the tangential trajectory of the moving point P of the focused light spot, and the calculation results are fed back to the control system.

[0058] S6: According to the tangential trajectory of the moving point P calculated in real time by the data processing module, the control system controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations;

[0059] The control system controls the motion mechanism to drive the laser processing head to perform processing operations according to the set laser processing trajectory, and simultaneously controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory according to the tangential trajectory of the moving point P of the focused light spot calculated in real time by the data processing module, to ensure that the focused light spot formed by the irradiation of the high-energy laser beam during the laser processing operation will not be defocused due to the problem of the incident angle of the laser beam, resulting in changes in energy intensity that affect the laser processing quality, thereby achieving high-quality laser welding, laser cutting or laser cladding processing operations on the complex surface A1.

[0060] S7: Ensure the correctness of the processing by monitoring the tangential trajectory and coordinates of the moving point P during laser processing. After the processing is completed, check and evaluate the processing quality.

[0061] According to the data processing module, the parameters of the surface line type are mapped in combination with the Bezier curve theory, A1 is mapped to the Bezier surface, and the laser focused light spot is used as an arbitrary moving point P on the Bezier surface. The coordinates are calculated in real time in combination with the coordinate calculation method of any moving point P (u, v) on the Bezier surface. The coordinates of the moving point P (u, v) of the focused light spot are derived synchronously and in real time to obtain the tangential trajectory of the moving point P of the focused light spot, and the calculation results are fed back to the control system.

[0062] The surface line parameters are extracted by analyzing the surface feature information. Based on the Bezier curve theory, the extracted surface line parameters are parameter mapped. The starting and ending points of the multi-order Bezier curve and the tangents of the control points can be used to obtain a unique Bezier curve to define the surface line parameters of the complex surface.

[0063] For the complex curved surface area A1 to be measured, it is divided into m equal parts, which are composed of n-order Bezier curves, namely, surface line types L1, L2, ..., L m , any Bezier curve is composed of n line segments formed by n+1 points, and a total of (n+1)*m vertices will be obtained. The position of the jth vertex corresponding to the i-th n-order Bezier curve is defined as P i,j , and the movement of the control point u corresponding to the j position on the curve to adjust the point at the v position on the surface area A1 will change the surface trajectory, and the coordinates are represented by P(u,v).

[0064] By parsing and extracting the parameters of the surface line type, the surface feature information is parsed and the surface line type parameters are extracted. According to the tangent of the start and end points and control points of the multi-order Bezier curve, a unique Bezier curve is obtained and the surface line type parameters of the complex surface are defined. The surface trajectory of the measured area A1 to be processed is constructed using the following formula:

[0065]

[0066] Where n represents the n-order Bezier curve; P i,j Indicates the position of the jth vertex corresponding to the i-th n-order Bezier curve; B n j represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the j-th vertex position, u represents the control point corresponding to the j-th position, and any control point P(u) on the i-th n-th order Bezier curve is a linear combination of the vertices on the corresponding curve; P(u,v) represents the coordinates of the point at the v position on the area A1 to be processed adjusted by the movement of the control point u corresponding to the j-th position on the curve.

[0067] For the measured area to be processed A1, it is divided into m equal parts, and the surface line types L1, L2, ..., L m, any Bezier curve is composed of n+1 points forming n line segments, resulting in (n+1)*m vertices. The complex surface is divided into m equal parts. The surface line type composed of n-order Bezier curves can obtain m P(u), recorded as P(u)0, P(u)1...P(u) m , where the Bezier curve corresponds to the point P(v) on the Bezier surface using the following formula:

[0068]

[0069] Where m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed.

[0070] According to the data processing module, the parameters of the surface line type are mapped in combination with the Bezier curve theory, A1 is mapped to the Bezier surface, and the laser focus point is used as an arbitrary moving point P on the Bezier surface. The coordinates are calculated in real time in combination with the coordinate calculation method of an arbitrary moving point P (u, v) on the Bezier surface. The following formula is used for the coordinate calculation of an arbitrary moving point P (u, v) on the Bezier surface:

[0071]

[0072] Where m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed; n represents the n-order Bezier curve; P i,j represents the j-th vertex position corresponding to the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, P(u,v) represents the coordinates of the point at the position v on the area A1 to be processed adjusted by the movement of the control point u at the j-th position on the curve; v represents the position on the area A1 to be processed.

[0073] The matrix for calculating the coordinates of P(u,v) uses the following formula:

[0074]

[0075] Among them, B n 0(u) represents the Bernstein polynomial corresponding to the nth-order Bezier curve passing through the first vertex position, B n 1(u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the second vertex position, B n n (u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the n+1th vertex position; m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves.m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed; n represents the n-order Bezier curve; P i,j represents the j-th vertex position corresponding to the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, P(u,v) represents the coordinates of the point at the position v on the area A1 to be processed adjusted by the movement of the control point u at the j-th position on the curve; v represents the position on the area A1 to be processed.

[0076] Based on the derivation of the coordinates of any point P (u, v) on the processing area A1, the tangential trajectory of the arbitrary point P on the surface can be obtained. The derivation calculation adopts the following formula:

[0077]

[0078] Among them, dP(u,v) represents the direction of the tangent trajectory through any point P(u,v) on the surface A1 to be processed, dP(u,v) represents the tangent line through any point P(u,v) on the area A1 (surface) to be processed, and d(u,v) represents the derivative of the motion of the control points u and v along the surface A1.

[0079] The whole working principle is as follows:

[0080] The process parameters of the processing operation are set in the control system of the laser processing device. The surface feature information of the area to be processed (complex curved surface) A1 measured by the line laser device coaxially installed with the three-dimensional measuring camera and the laser processing head of the laser processing device and the surface line parameters obtained by analysis and extraction are fed back to the data processing module. The laser processing head of the laser processing device is controlled by the control system and the motion mechanism to irradiate the laser on the area to be processed (complex curved surface) A1 to form a focused light spot as an arbitrary moving point P of the trajectory;

[0081] The laser processing trajectory planning of the programming teaching moving point P can cover the area to be processed (complex surface) A1, and based on the coordinate calculation method of any point P (u, v) on the Bezier surface, the laser focus point is used as an arbitrary moving point P to calculate the coordinates P (u, v) in real time, and the coordinates of the moving point P (u, v) of the focusing point are synchronously derived to obtain the real-time tangential trajectory of the moving point P of the focusing point on the surface and feed it back to the control system. The linear laser emitted by the coaxially installed line laser device irradiates the surface of the area to be processed (complex surface) A1, and extends to both sides with the moving point P of the focusing point as the center point;

[0082] The control system controls the motion mechanism to drive the laser processing head to perform processing operations according to the set laser processing trajectory, and simultaneously controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory according to the tangential trajectory of the moving point P of the focused light spot calculated in real time by the data processing module, so as to ensure that the focused light spot formed by the irradiation of the high-energy laser beam during the laser processing operation will not be defocused due to the problem of the incident angle of the laser beam, resulting in changes in energy intensity that affect the laser processing quality.

[0083] The linear laser emitted by the line laser device with the moving point P of the focused light spot as the center point extending to both sides is used for auxiliary target marking of the moving point P of the focused light spot on the A1 complex surface to ensure that the 3D measurement camera can recognize it efficiently. At the same time, the linear laser extending to both sides can also avoid distortion of the point cloud data measured by the 3D measurement camera when there is light interference or partial occlusion on part of the A1 complex surface.

[0084] For the laser processing system, the functions of the three-dimensional measurement camera, line laser device, data processing module, laser processing head, laser processing device, control system and motion mechanism are as follows:

[0085] 3D measurement camera: used to observe the complex surface A1 in the area to be processed, collect the point cloud data and surface feature information of A1, and simultaneously analyze and extract the surface line parameters;

[0086] Line laser device: coaxially installed with the laser processing head, used as an auxiliary target for the moving point P of the focused light spot irradiated by the laser processing head. When the irradiated linear laser has light interference on the complex curved surface A1, it can increase the contrast of the moving point P of the focused light spot. When there is partial occlusion on the complex curved surface A1, interference fringes will appear, effectively ensuring that the recognition of the 3D measurement camera and the point cloud data are not distorted. The line laser device includes a line laser, a 3D measurement camera, a laser processing head, and a laser processing device.

[0087] Data processing module: used to combine the surface line parameters of the complex surface A1 observed and analyzed by the three-dimensional measurement camera with the Bezier curve and the surface theory method to perform parameter mapping processing, and calculate the coordinates of the moving point P (u, v) of the focusing light spot irradiated by the laser processing head on the complex surface A1 and the tangential trajectory of the moving point P of the focusing light spot in real time;

[0088] Laser processing head: used to perform laser processing operations on the target area. Different laser processing heads correspond to the processing operations of laser welding, laser cutting, and laser cladding.

[0089] Laser processing device: used to generate and emit high-energy laser beam to the laser processing head;

[0090] Control system: used to control the laser processing device and set the process parameters of the processing operation, control and plan the processing operation trajectory of the laser processing head, and adjust the posture angle of the laser processing head during the processing operation;

[0091] Motion mechanism: used to load the laser processing head to execute the processing operation trajectory planned by the control system, and adjust the posture angle of the laser processing head in real time according to the control system instructions.

[0092] Furthermore, the present embodiment also provides a laser processing system based on Bezier curve surface mapping, including: a construction module, which obtains a to-be-processed area A1 through a three-dimensional measurement camera, where A1 represents a complex surface, collects point cloud data information and profile feature information of A1, and constructs a surface line type;

[0093] The parsing module parses and extracts the parameters of the surface line type, and substitutes the parameters of the surface line type into the data processing module to obtain the surface information of the laser processing;

[0094] The calibration module ensures that the linear laser is correctly irradiated on the area A1 to be processed by calibrating the linear laser of the line laser device, and obtains a moving point P, where the moving point P represents a moving point in the focused light spot;

[0095] The output module outputs the trajectory planning for subsequent processing based on extending to both sides with the moving point P as the center point;

[0096] A mapping module sets the laser processing parameters in the control system, performs parameter mapping on the surface line type parameters according to the data processing module combined with the Bezier curve theory, and defines the motion trajectory of the laser processing head;

[0097] The adjustment module controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations according to the tangential trajectory of the moving point P calculated in real time by the data processing module;

[0098] The evaluation module ensures the correctness of the processing by monitoring the tangential trajectory and coordinates of the moving point P during the laser processing. After the processing is completed, the processing quality is checked and evaluated.

[0099] Example 2

[0100] Reference Figure 1 - Figure 4 , which is the second embodiment of the present invention, provides a laser processing method based on Bezier curve surface mapping. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0101] This embodiment also provides a computer device, which is suitable for the case of a laser processing method based on Bezier curve surface mapping, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement the laser processing method based on Bezier curve surface mapping proposed in the above embodiment.

[0102] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0103] This embodiment further provides a storage medium on which a computer program is stored. When the program is executed by a processor, the laser processing method based on Bezier curve surface mapping as proposed in the above embodiment is implemented.

[0104] In summary, the three-dimensional measurement camera of this scheme measures the area to be processed (complex surface) A1; the data processing module performs Bezier curve and surface mapping according to the measured surface line parameters to calculate the data of the area to be processed A1; the process parameters of the laser processing device to perform laser processing operations (the laser processing device has the functions of laser welding, laser cutting or laser cladding processing after matching different laser processing heads) are set in the control system; the calibration line laser device is used as an auxiliary target of the laser focusing light point. When the motion mechanism loads the laser processing head to perform the laser processing operation according to the planned trajectory, the control system can combine the data processing module to calculate the coordinates of the moving point P of the laser focusing light point and the data of the tangential trajectory in real time, and command the motion mechanism to control the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory, so as to ensure that the focusing light point formed by the irradiation of the high-energy laser beam during the laser processing operation will not be defocused due to the problem of the incident angle of the laser beam, resulting in changes in energy intensity that affect the laser processing quality. The present invention is helpful to realize the laser processing operation of the posture angle of the surface line type adaptively fitting various irregular complex surfaces on the complex surface A1, improve the degree of automated maintenance operations, and ensure the consistency of quality after maintenance.

[0105] Example 3

[0106] Reference Figure 1 - Figure 4 , which is the third embodiment of the present invention, provides a laser processing method based on Bezier curve surface mapping. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0107] This embodiment is directed to a laser processing method based on Bezier curve surface mapping. First, a three-dimensional measurement camera is used to measure the processing area A. 1( The complex curved front fork pipe is scanned and measured to obtain the point cloud data and surface feature information of A1, and the surface line parameters are extracted by analysis to build the surface line model of A1.

[0108] Then, the 3D measurement camera, line laser device and laser processing head are integrated and installed. The line laser device is coaxially installed with the laser processing head to project auxiliary line laser lines on A1 to enhance the contrast of the focused light spot. The data processing module receives the A1 profile data input by the 3D measurement camera, and combines the Bezier curve theory to perform parameter mapping on the surface line parameters of A1 to obtain the Bezier surface model of A1.

[0109] The processing parameters are input into the control system, including laser power, scanning speed, etc. The control system drives the laser processing device to emit a high-energy laser beam, and forms a laser focus spot on A1 through the laser processing head as the moving point P. At the same time, the data processing module calculates the coordinates P(u,v) of the moving point P on the Bezier surface in real time, and derives P(u,v) to obtain the tangential trajectory of the moving point P, which is fed back to the control system.

[0110] The control system controls the motion mechanism to drive the laser processing head to move along the A1 surface according to the set process parameters and the tangential trajectory of P, and synchronously adjusts the attitude angle of the laser processing head to make the laser beam incident vertically on the A1 surface. The laser line projected by the line laser device extends to both sides with the moving point P as the center, which is used to assist the 3D measurement camera to track and identify the moving point P.

[0111] During the processing, the motion trajectory and coordinates of the moving point P are monitored in real time to ensure smooth processing. After the processing is completed, the cladding quality of the A1 surface is inspected and evaluated.

[0112] The data of this embodiment are shown in the following table:

[0113] Table 1 is a comparison table of cladding quality at the same monitoring point between the existing technology and our solution

[0114] Contrast type Prior art This program Welding process efficiency (unit: cm^2 / min) 80 140 Surface cutting kerf roughness Ra(μm) 5 3 Cutting accuracy (μm) ±80 ±32 Surface cladding dilution rate (%) 8 5.4 Thickness deviation of curved cladding layer (mm) ±0.1 ＜±0.06

[0115] It can be seen from Table 1 above that, compared with the prior art, the solution of the present invention has obvious improvements in three key indicators: welding processing efficiency, surface cutting seam roughness, and cutting processing accuracy.

[0116] The welding process efficiency has increased by 75%, mainly due to the Bezier surface modeling method and real-time trajectory planning. The traditional method uses offline programming, which makes it difficult to accurately fit complex surfaces, resulting in a large number of deceleration sections that slow down efficiency. This solution is based on measured surface data, uses Bezier curves to accurately model the surface, and generates tangential trajectories in real time, making the laser processing head move more smoothly, reducing deceleration sections, and thus greatly improving efficiency.

[0117] The surface kerf roughness Ra is reduced by 40%, mainly due to the real-time posture angle adjustment. The traditional method is difficult to adjust the laser beam incident angle according to the local curvature change, so that the laser cannot irradiate the curved surface vertically in some areas (the light spot is out of focus), resulting in insufficient molten pool energy, insufficient kerf ablation and gasification, and increased defects. However, this solution calculates the tangential trajectory through the data processing module, and adjusts the processing head posture angle in conjunction with the motion mechanism, so that the laser is incident vertically to form an ideal keyway-shaped molten pool, thereby greatly improving the cladding quality.

[0118] The machining accuracy is improved by 62.5%, which is because the Bezier surface model has higher fitting accuracy for complex surfaces, and the real-time trajectory planning avoids the cumulative error of traditional offline programming.

[0119] The cladding dilution rate was reduced by 32.5%, mainly because this scheme ensured vertical laser incidence, which allowed the laser to melt the powder material more fully, reducing the energy fluctuation of the molten pool caused by the defocusing of the laser focus spot and the ablation of some alloy elements of the substrate or powder material.

[0120] The thickness deviation of the cladding layer is nearly doubled. Vertical incidence allows more laser energy to be used for actual melting of materials rather than reflection and diffraction, thereby improving energy utilization efficiency, reducing energy fluctuations in the molten pool, allowing the powder material to melt more fully, and making the thickness of the cladding layer more consistent.

[0121] In summary, compared with the existing technology, the scheme of the present invention proposes innovative technologies such as Bezier surface modeling, real-time planning of tangential trajectories, and adaptive adjustment of attitude angles, which significantly improves the efficiency and quality of laser cladding processing of complex surfaces, and has obvious innovation and practical value. Compared with the existing technology, the scheme of the present invention has made significant breakthroughs in multiple key indicators, thanks to innovative Bezier surface modeling, real-time planning of tangential trajectories, adaptive adjustment of attitudes and other technologies, and has significant innovation and practical value. These innovative technologies effectively solve the difficulties in laser processing of complex surfaces and provide strong support for the realization of efficient and high-quality precision laser manufacturing.

[0122] Based on the above experiment, we also use the following data for comparison. We have installed and calibrated a high-precision 3D measurement camera system on the workstation to accurately measure a complex surface (area A1 to be processed). The area A1 is composed of a variety of heterogeneous materials and has a highly irregular geometric shape. In order to verify the practicality and technical advantages of the present invention, the 3D measurement camera system is first used to capture the point cloud data and surface feature information of the A1 area. Through the software algorithm, these data are converted into specific parameters of the surface line type and transmitted to the data processing module in real time for further analysis.

[0123] The data processing module combines the Bezier curve theory to perform complex parameter mapping on the extracted surface line parameters, and virtually maps the complex surface A1 into a series of operable Bezier surfaces. Subsequently, the line laser device is precisely calibrated to ensure that the linear laser it emits accurately irradiates the area to be processed A1. At this time, the moving point P (the moving point in the focused light spot) is determined and used as the center point for subsequent processing.

[0124] Using the control system and motion mechanism, we developed a trajectory planning for laser processing based on the moving point P of the focused light spot. Trajectory planning involves extending from the moving point P to both sides to ensure that the laser processing can cover the entire A1 area. In this process, each step is completed through programming and teaching, ensuring the accuracy and reproducibility of the operation.

[0125] Table 2 is a comparison table of various parameters between our solution test area and the existing technology test area

[0126] parameter Test area A1 Prior Art Area B1 <![CDATA[Point cloud density (points / cm 2 )]]> 475 298 Parameter extraction accuracy (mm) 0.01 0.05 Trajectory planning time (min) 2 5 Processing accuracy(mm) ±0.02 ±0.1 <![CDATA[Processing speed (cm 2 / min)]]> 10 7 Data processing efficiency(s) 0.5 2

[0127] As can be seen from Table 2, compared with the existing technology (area B1), this experiment shows significant advantages in multiple key indicators. The point cloud density increased by nearly 67%, which directly improved the refinement of surface modeling and made subsequent processing more accurate. The parameter extraction accuracy increased by five times, which means that the microstructure and characteristics of the material can be determined more accurately before laser processing, thereby optimizing the processing parameters.

[0128] The test area A1 and the prior art area B1 are both complex curved surface workpieces of the same material and similar geometric shapes, and are comparable. The main differences between the two are:

[0129] (1) A1 is processed by the method of the present invention, and B1 is processed by the prior art method.

[0130] (2) The surface complexity of A1 is slightly higher than that of B1, and it contains more irregular bends and inclined surfaces.

[0131] (3) The dimensions of A1 and B1 are similar, both approximately 200 mm × 200 mm × 50 mm.

[0132] By comparing the processing results of A1 and B1, the advantages of the method of the present invention over the prior art can be intuitively evaluated. Although the surface of A1 is more complex, it still shows obvious advantages in various indicators, which fully demonstrates the excellent performance of the method in processing difficult and complex surfaces.

[0133] In addition, trajectory planning time has been reduced by 60%, greatly improving overall work efficiency. In terms of laser processing accuracy, the present invention achieves a high accuracy of ±0.02 mm, which is five times the accuracy of the existing technology, which is particularly important in the field of high-precision processing, such as aerospace component manufacturing. The increase in processing speed not only reduces production costs, but also increases the throughput of the production line, and the data processing time is significantly shortened (from 2 seconds to 0.5 seconds), which directly affects the overall setting time, which is shortened from 5 minutes to 1 minute.

[0134] Through the detailed comparison of these data, it can be clearly seen that the present invention in the embodiments shows significant innovation and practical novelty compared with the prior art, which not only improves the processing efficiency and precision, but also optimizes the operation process. These improvements make the present invention have important industrial application value.

[0135] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A laser processing method based on Bezier curve surface mapping, characterized in that: include, The area A1 to be processed is obtained by a three-dimensional measurement camera, wherein A1 represents a complex curved surface, cloud data information and profile feature information of the points of A1 are collected, and a curved surface line type is constructed; By analyzing and extracting the parameters of the surface line type, the parameters of the surface line type are substituted into the data processing module to obtain the surface information of laser processing; By calibrating the linear laser of the line laser device, it is ensured that the linear laser is correctly irradiated on the area to be processed A1, and a moving point P is obtained, wherein the moving point P represents a moving point in the focused light spot; Take the moving point P as the center point and extend to both sides to output the trajectory planning for subsequent processing; Set the laser processing parameters in the control system, map the parameters of the surface line type according to the data processing module combined with the Bezier curve theory, and define the motion trajectory of the laser processing head; According to the tangential trajectory of the moving point P calculated in real time by the data processing module, the control system controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations; By monitoring the tangential trajectory and coordinates of the moving point P during laser processing, the processing process is ensured to be correct. After the processing is completed, the processing quality is checked and evaluated.

2. The laser processing method based on Bezier curve and surface mapping as claimed in claim 1, characterized in that: The data processing module is combined with the Bezier curve theory to perform parameter mapping on the parameters of the surface line type, A1 is mapped to the Bezier surface, the laser focused light spot is used as an arbitrary moving point P on the Bezier surface, the coordinates are calculated in real time in combination with the coordinate calculation method of any moving point P (u, v) on the Bezier surface, the coordinates of the moving point P (u, v) of the focused light spot are derived synchronously and in real time to obtain the tangential trajectory of the moving point P of the focused light spot, and the calculation result is fed back to the control system.

3. The laser processing method based on Bezier curve and surface mapping as claimed in claim 2, characterized in that: By analyzing and extracting the parameters of the surface line type, the surface feature information is analyzed and the surface line type parameters are extracted. According to the tangent of the starting and ending points and the control points of the multi-order Bezier curve, a unique Bezier curve is obtained and the surface line type parameters of the complex surface are defined. The surface trajectory of the measured area A1 to be processed is constructed using the following formula: Where n represents the n-order Bezier curve; P i,j Indicates the position of the jth vertex corresponding to the i-th n-order Bezier curve; B n j Represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the j-th vertex position, u represents the control point corresponding to the j-th position, and any control point P(u) on the i-th n-th order Bezier curve is a linear combination of the vertices on the corresponding curve; P(u,v) represents the coordinates of the point at the v position on the area A1 to be processed corresponding to the movement adjustment of the control point u corresponding to the j-th position on the curve.

4. The laser processing method based on Bezier curve and surface mapping as claimed in claim 3, characterized in that: The measured area A1 to be processed is divided into m equal parts of surface line types L1, L2, ..., L composed of n-order Bezier curves. m , any Bezier curve is composed of n+1 points forming n line segments, resulting in (n+1)*m vertices. The complex surface is divided into m equal parts. The surface line type composed of n-order Bezier curves can obtain m P(u), recorded as P(u)0, P(u)1...P(u) m , where the Bezier curve corresponds to the point P(v) on the Bezier surface using the following formula: Where m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed.

5. The laser processing method based on Bezier curve and surface mapping as claimed in claim 4, characterized in that: The data processing module is combined with the Bezier curve theory to perform parameter mapping on the parameters of the surface line type, and A1 is mapped to a Bezier surface. The laser focus point is used as an arbitrary moving point P on the Bezier surface, and the coordinates are calculated in real time in combination with the coordinate calculation method of an arbitrary moving point P (u, v) on the Bezier surface. The coordinate calculation of an arbitrary moving point P (u, v) on the Bezier surface adopts the following formula: Where i represents an i-order Bezier curve; v represents the position on the area A1 to be processed; n represents an n-order Bezier curve; P i,j represents the j-th vertex position of the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, and P(u,v) represents the coordinates of the point at the v-th position on the processing area A1 adjusted by the movement of the control point u corresponding to the j-th position on the curve.

6. The laser processing method based on Bezier curve and surface mapping as claimed in claim 5, characterized in that: The matrix for the coordinate calculation of P(u,v) adopts the following formula: Among them, B n 0(u) represents the Bernstein polynomial corresponding to the nth-order Bezier curve passing through the first vertex position, B n 1(u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the second vertex position, B n n (u) represents the Bernstein polynomial corresponding to the n-th order Bezier curve passing through the n+1th vertex position; m represents the surface line type L1, L2, ... L composed of m multi-order Bezier curves. m ; i represents i multi-order Bezier curves; v represents the position on the area A1 to be processed; n represents the n-order Bezier curve; P i,j represents the j-th vertex position of the i-th n-order Bezier curve; u represents the control point corresponding to the j-th position, and P(u,v) represents the coordinates of the point at the v-th position on the processing area A1 adjusted by the movement of the control point u corresponding to the j-th position on the curve.

7. The laser processing method based on Bezier curve and surface mapping as claimed in claim 6, characterized in that: By taking the derivative of the coordinates of any moving point P (u, v) on the processing area A1, the tangential trajectory of the arbitrary point P on the surface can be obtained. The derivative calculation adopts the following formula: Among them, dP(u,v) represents the direction of the tangent trajectory through any point P(u,v) on the surface A1 to be processed, dP(u,v) represents the tangent line through any point P(u,v) on the area A1 to be processed, and d(u,v) represents the derivative of the motion of the control points u and v along the surface A1.

8. A laser processing system based on Bezier curve and surface mapping, based on the laser processing method based on Bezier curve and surface mapping according to any one of claims 1 to 7, characterized in that: Also includes, A construction module obtains the area A1 to be processed through a three-dimensional measurement camera, wherein A1 represents a complex surface, collects the cloud data information and surface feature information of the points of A1, and constructs the surface line type; The parsing module parses and extracts the parameters of the surface line type, and substitutes the parameters of the surface line type into the data processing module to obtain the surface information of the laser processing; A calibration module, which ensures that the linear laser is correctly irradiated on the area to be processed A1 by calibrating the linear laser of the line laser device, and obtains a moving point P, wherein the moving point P represents a moving point in the focused light spot; The output module takes the moving point P as the center point and extends to both sides to output the trajectory planning for subsequent processing; A mapping module sets the laser processing parameters in the control system, performs parameter mapping on the surface line type parameters according to the data processing module combined with the Bezier curve theory, and defines the motion trajectory of the laser processing head; The adjustment module controls the laser processing head to perform adaptive adjustment of the posture angle along the tangential trajectory and perform processing operations according to the tangential trajectory of the moving point P calculated in real time by the data processing module; The evaluation module ensures the correctness of the processing by monitoring the tangential trajectory and coordinates of the moving point P during the laser processing. After the processing is completed, the processing quality is checked and evaluated.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the laser processing method based on Bezier curve and surface mapping described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the laser processing method based on Bezier curve and surface mapping described in any one of claims 1 to 7 are implemented.

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