Laser pulse energy control method and system for surface treatment

Abstract

The present invention provides a laser pulse energy control method and system for surface treatment, and relates to the field of laser pulse energy control technology. The method comprises: controlling a laser probe within a test cycle so that the laser spot moves on the surface of a workpiece, and changing the power and moving speed of the laser probe at multiple moments, and measuring the first temperature data of multiple positions through an infrared camera, thereby determining the control function between the temperature of the spot on the trajectory between adjacent moments and the power and moving speed of the laser probe, and obtaining the first area of ​​the spot on the surface of the workpiece, the size of the area to be processed, the preset processing time and the preset processing temperature, and then determining the working moving speed and working power of the laser probe in combination with the control function, thereby controlling the laser probe to perform surface treatment on the workpiece. According to the present invention, various factors are comprehensively considered to reasonably set the power and moving speed of the laser probe to improve the control accuracy of the laser pulse energy.

Description

Technical Field

[0001] The present invention relates to the technical field of laser pulse energy control, and in particular to a laser pulse energy control method and system for surface treatment. Background Art

[0002] In the related technology, although the control and use of lasers can be achieved, the control accuracy of laser pulse energy is poor. During the use of lasers, excessive laser pulse energy will cause irreversible damage to the workpiece, and excessive laser pulse energy will cause the workpiece to be unable to form a melting layer, thereby making it impossible to implement subsequent work steps.

[0003] The information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Summary of the invention

[0004] The embodiments of the present invention provide a laser pulse energy control method and system for surface treatment, which can solve the technical problem of low laser pulse energy control accuracy.

[0005] According to a first aspect of the present invention, there is provided a laser pulse energy control method for surface treatment, comprising:

[0006] During the test cycle, the laser probe is controlled to move above the surface of the workpiece so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple times during the test cycle;

[0007] By means of an infrared camera, at the i+1th moment in the test cycle, first temperature data of a plurality of positions on the trajectory of the light spot moving within the time interval between the i-th moment and the i+1-th moment are measured, wherein i is a positive integer;

[0008] Determine a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments;

[0009] Acquire a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature;

[0010] Determine the working moving speed and working power of the laser probe when performing surface treatment on the area to be processed on the surface of the workpiece according to the first area of ​​the light spot on the surface of the workpiece, the size of the area to be processed on the surface of the workpiece, the preset processing time, the preset processing temperature and the control function;

[0011] According to the working moving speed and the working power, the laser probe is controlled to perform surface treatment on the to-be-processed area on the surface of the workpiece.

[0012] According to the present invention, determining a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments includes:

[0013] Determine a first average temperature of the trajectory where the light spot moves within the time interval between the i-th moment and the i+1-th moment according to first temperature data of a plurality of positions on the trajectory where the light spot moves within the time interval between the i-th moment and the i+1-th moment;

[0014] The control function is determined according to the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment.

[0015] According to the present invention, the control function is determined according to the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, including:

[0016] According to the formula

[0017]

[0018] Determine the first undetermined coefficient equation, where T 1,(i)-(i+1) is the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, P i is the power of the laser probe at the i-th moment, v i is the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, α 1 , α 2 , α 3 , α 4 and α 5 is the first undetermined coefficient;

[0019] According to the present invention, the first undetermined coefficient is solved according to the first average temperature of the trajectory of the light spot moving in multiple time intervals, the power of the laser probe at multiple moments, and the moving speed of the laser probe in multiple time intervals to obtain the solution value of the first undetermined coefficient;

[0020] The control function is determined according to the solved value of the first undetermined coefficient and the first undetermined coefficient equation.

[0021] According to the present invention, the working moving speed and working power of the laser probe when performing surface treatment on the area to be processed on the surface of the workpiece are determined according to the first area of ​​the light spot on the surface of the workpiece, the size of the area to be processed on the surface of the workpiece, the preset processing time, the preset processing temperature and the control function, including:

[0022] Determine the length of a processing path of the light spot in the area to be processed on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece;

[0023] Determining the constraint conditions of the optimization model according to the length of the processing path, the preset processing time, the preset processing temperature and the control function;

[0024] Determining an objective function of an optimization model according to the length of the processing path and the preset processing time;

[0025] The optimization model is solved according to the constraint conditions and objective function of the optimization model to obtain the working moving speed and working power of the laser probe.

[0026] According to the present invention, determining the length of a processing path of the area to be processed by the light spot on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece includes:

[0027] Determine the length and width of the area to be processed according to the size of the area to be processed;

[0028] According to the formula

[0029]

[0030] Determine the length L of the processing path of the light spot in the area to be processed on the surface of the workpiece, where l is the length of the area to be processed, w is the width of the area to be processed, and S 1 is the first area, k is the overlapping ratio of two adjacent rows of paths of the light spot, and roundup is the upward rounding function.

[0031] According to the present invention, the constraint conditions of the optimization model are determined according to the length of the processing path, the preset processing time, the preset processing temperature and the control function, including:

[0032] According to the formula

[0033]

[0034] (1-σ)T p ≤TE ≤(1+σ)T p

[0035] P w ≤P max

[0036] v w ≤v max

[0037] Determine the constraints of the optimization model, where L is the length of the moving path of the light spot in the area to be processed on the surface of the workpiece, w is the width of the area to be processed, S 1 is the first area, k is the overlap ratio of two adjacent lines of the spot, roundup is the upward rounding function, v p is the preset moving speed, v w is the unknown value of the working moving speed, ΔT p is the preset processing time, P w is the undetermined value of the working power, T E To estimate the processing temperature, T p is the preset processing temperature, σ is the preset proportionality coefficient, P max is the maximum power of the laser probe, v max is the maximum moving speed of the laser probe, α 1,F is α 1 The solution value of α 2,F is α 2 The solution value of α 3,F is α 3 The solution value of α 4,F is α 4 The solution value of α 5,F is α 5 The solution value of .

[0038] According to the present invention, the objective function of the optimization model is determined according to the length of the moving path and the preset processing time, including:

[0039] According to the formula

[0040]

[0041] Determine the objective function of the optimization model, where min is the minimization function.

[0042] According to a second aspect of the present invention, there is provided a laser pulse energy control system for surface treatment, comprising:

[0043] A first control module controls the laser probe to move above the workpiece surface during a test cycle so that the laser spot moves on the workpiece surface, and changes the power and moving speed of the laser probe at multiple times during the test cycle;

[0044] a temperature data determination module, which measures, by means of an infrared camera, at the i+1th moment in a test cycle, first temperature data of a plurality of positions on a trajectory where the light spot moves within a time interval between the i-th moment and the i+1th moment, wherein i is a positive integer;

[0045] A control function determination module, which determines a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments and the moving speed of the laser probe at multiple moments;

[0046] A first acquisition module is used to acquire a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature;

[0047] A first determination module determines, according to a first area of ​​the light spot on the workpiece surface, a size of the to-be-processed area on the workpiece surface, a preset processing time, a preset processing temperature, and the control function, a working moving speed and a working power of the laser probe when performing surface treatment on the to-be-processed area on the workpiece surface;

[0048] The second control module controls the laser probe to perform surface treatment on the to-be-processed area on the surface of the workpiece according to the working moving speed and the working power.

[0049] Technical effect: According to the present invention, the movement of the laser probe can be controlled within the test cycle so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple moments, and the first temperature data of multiple positions on the trajectory of the light spot moving between adjacent moments are measured by an infrared camera, and then the control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe is determined, so as to accurately describe the relationship between the moving speed and power of the laser probe and the temperature of the workpiece surface, and obtain the first area of ​​the light spot on the workpiece surface, the size of the area to be processed on the workpiece surface, the preset processing time and the preset processing temperature, and then determine the working moving speed and working power of the laser probe in combination with the control function, so as to control the laser probe to perform surface treatment on the area to be processed on the workpiece surface, comprehensively consider various factors, reasonably set the power and moving speed of the laser probe, and improve the control accuracy of the laser pulse energy. When determining the control function, the first undetermined coefficient equation can be constructed according to the positive correlation between the average temperature of each position in the trajectory of the light spot movement and the power of the laser probe and the inverse correlation between the average temperature of each position in the trajectory of the light spot movement and the moving speed of the laser probe, and the solution value of the first undetermined coefficient that minimizes the overall error can be obtained, and then the control function that can adapt to the current environment and the current batch of workpiece materials can be determined to accurately describe the relationship between the power and moving speed of the laser probe and the temperature of the workpiece surface, and provide an accurate data basis for the stable control of the laser pulse energy. When determining the length of the processing path, the size information of the area to be processed of the workpiece can be obtained, and the number of times the laser switches the processing path on the area to be processed is determined according to the width of the area to be processed, the first area of ​​the light spot on the surface of the workpiece, and the overlap of the trajectory caused by the light spot moving on the area to be processed, and then the length of the processing path of the light spot on the surface of the workpiece to be processed is determined in combination with the length of the area to be processed, and the calculation error is reduced by rounding up the function, so as to accurately calculate the length of the processing path of the laser probe, thereby improving the working efficiency of the laser probe. When determining the working power and the working moving speed, the time required for the laser probe to process the workpiece can be determined by the distance the laser probe needs to move to switch the processing path, the length of the processing path, and the working moving speed of the laser probe. The processing temperature of the area to be processed is determined based on the estimated processing temperature and the relationship between the working power and the moving speed of the laser probe. Then, combined with the rated parameters of the laser probe, various factors are comprehensively considered, constraints are set in a targeted manner, and the objective function of the optimization model is determined, so that the laser probe can complete the processing within the preset processing time and make the area to be processed reach the preset processing temperature, and complete the processing work with the minimum energy consumption, thereby improving the control accuracy of the laser pulse energy, reducing the energy consumption of the laser probe, and improving the working efficiency of the laser probe.

[0050] It should be understood that the above general description and the following detailed description are exemplary and explanatory only and do not limit the present invention. Other features and aspects of the present invention will become more apparent from the following detailed description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other embodiments can be obtained based on these drawings without creative work.

[0052] Figure 1 A schematic flow chart of a laser pulse energy control method for surface treatment according to an embodiment of the present invention is exemplarily shown;

[0053] Figure 2 A schematic diagram exemplarily shows a workpiece according to an embodiment of the present invention;

[0054] Figure 3 A schematic diagram exemplarily shows two adjacent rows of processing paths of laser spots according to an embodiment of the present invention;

[0055] Figure 4 A schematic diagram of a laser pulse energy control system for surface treatment according to an embodiment of the present invention is exemplarily shown. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0058] Figure 1 A schematic flow chart of a laser pulse energy control method for surface treatment according to an embodiment of the present invention is exemplarily shown, the method comprising:

[0059] Step S101, during a test cycle, controlling the laser probe to move above the workpiece surface so that the laser spot moves on the workpiece surface, and changing the power and moving speed of the laser probe at multiple times during the test cycle;

[0060] Step S102, measuring, by means of an infrared camera, at the i+1th moment in the test cycle, first temperature data of a plurality of positions on a trajectory along which the light spot moves within a time interval between the i-th moment and the i+1-th moment, where i is a positive integer;

[0061] Step S103, determining a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments;

[0062] Step S104, obtaining a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature;

[0063] Step S105, determining the working moving speed and working power of the laser probe when performing surface treatment on the area to be processed on the surface of the workpiece according to the first area of ​​the light spot on the surface of the workpiece, the size of the area to be processed on the surface of the workpiece, the preset processing time, the preset processing temperature and the control function;

[0064] Step S106, controlling the laser probe to perform surface treatment on the to-be-processed area on the surface of the workpiece according to the working moving speed and the working power.

[0065] According to the laser pulse energy control method for surface treatment of the present invention, the movement of the laser probe can be controlled within the test cycle so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple moments, and the first temperature data of multiple positions on the trajectory of the light spot moving between adjacent moments are measured by an infrared camera, and then the control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe is determined, so that the relationship between the moving speed and power of the laser probe and the temperature of the workpiece surface can be accurately described, and the first area of ​​the light spot on the workpiece surface, the size of the area to be processed on the workpiece surface, the preset processing time and the preset processing temperature are obtained, and then the working moving speed and working power of the laser probe are determined in combination with the control function, so as to control the laser probe to perform surface treatment on the area to be processed on the workpiece surface, and comprehensively consider various factors to reasonably set the power and moving speed of the laser probe to improve the control accuracy of the laser pulse energy.

[0066] According to an embodiment of the present invention, in step S101, since the materials of the workpieces are different, the thermal conductivity of the workpieces is different, and the environments during processing may be different, so that when the laser of the same power is irradiated on the surface of the workpiece, the temperature of the surface of the workpiece may be different. Therefore, a test cycle can be set, and through the test within the test cycle, the relationship between the power and moving speed of the laser probe and the temperature of the workpiece surface when processing the surfaces of the current batch of workpieces under the current environment is determined. During the test cycle, the laser probe is controlled to move above the surface of the workpiece so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple moments during the test cycle. That is, during the test cycle, the power and moving speed of the laser probe are adjusted, and the laser probe is controlled to process the workpiece, so that the surface temperature of the workpiece increases or even forms a melt layer, and then the temperature of the workpiece surface is measured.

[0067] According to an embodiment of the present invention, in step S102, the infrared camera is used to measure the first temperature data of multiple positions on the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment in the test cycle, where i is a positive integer. For example, the laser spot has a certain area, and the shape of the laser spot can be circular. When the laser probe is controlled to process the workpiece, a strip-shaped moving trajectory will be left. The width of the trajectory is the diameter of the laser spot. The infrared camera can be used to measure the first temperature data of multiple positions on the trajectory of the light spot moving between each moment in the test cycle. During the measurement process, any position within the trajectory of the light spot movement can be measured, and the present invention does not set any limitation to this.

[0068] According to an embodiment of the present invention, in step S103, a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe is determined based on the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments, including: determining the first average temperature of the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment based on the first temperature data of multiple positions on the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment; determining the control function based on the first average temperature of the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment.

[0069] According to an embodiment of the present invention, based on the first temperature data of multiple positions on the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment, the first average temperature of the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment (that is, the average value of the first temperature data of each position) is determined, and then based on the relationship between the first average temperature of the trajectory where the light spot moves in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, an equation with undetermined coefficients is constructed to determine the control function.

[0070] According to an embodiment of the present invention, the control function is determined according to the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, including: determining the first undetermined coefficient equation according to formula (1),

[0071]

[0072] Among them, T 1,( i)-(i +1) is the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, P i is the power of the laser probe at the i-th moment, v i is the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, α 1 , α 2 , α 3 , α 4 and α 5 is the first undetermined coefficient; according to the first average temperature of the trajectory of the light spot moving in multiple time intervals, the power of the laser probe at multiple moments and the moving speed of the laser probe in multiple time intervals, the first undetermined coefficient is solved to obtain the solution value of the first undetermined coefficient; according to the solution value of the first undetermined coefficient and the first undetermined coefficient equation, the control function is determined.

[0073] According to an embodiment of the present invention, in formula (1), P i is the power of the laser probe at the i-th moment, and the power of the laser probe is positively correlated with the first average temperature of the trajectory of the light spot moving on the workpiece surface. The greater the power of the laser probe, the greater the laser pulse energy output by the laser probe, and the faster the temperature increase rate of the irradiated position on the workpiece surface between the i-th moment and the i+1-th moment, the higher the average temperature, and v iis the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment. The moving speed is inversely correlated with the first temperature data of the trajectory of the light spot moving on the workpiece surface. The faster the moving speed of the laser probe, the shorter the residence time of the laser spot at each position on the irradiated workpiece, the less energy received by a single position on the workpiece surface, the slower the temperature increase speed of the irradiated position on the workpiece, and the lower the average temperature. The first undetermined coefficient equation is constructed through the above positive correlation and inverse correlation relationship, and the undetermined coefficient α is established. 1 , α 2 , α 3 , α 4 , α 5 , which can optimize the accuracy of the relationship between the first average temperature of the trajectory of the light spot moving on the workpiece surface and the moving speed and power of the laser probe in the time interval between the i-th moment and the i+1-th moment, and solve the first undetermined coefficient equation through the first average temperature of the trajectory of the light spot moving in the time interval of adjacent moments, the power of the laser probe at multiple moments and the moving speed of the laser probe in the time interval of adjacent moments, to obtain the solution value of the first undetermined coefficient, and then determine the control function.

[0074] In this way, based on the positive correlation between the average temperature of each position in the trajectory of light spot movement and the power of the laser probe and the negative correlation between the average temperature of each position in the trajectory of light spot movement and the moving speed of the laser probe, the first undetermined coefficient equation can be constructed to obtain the solution value of the first undetermined coefficient that minimizes the overall error, and then determine the control function that can adapt to the current environment and the current batch of workpiece materials, so as to accurately describe the relationship between the power and moving speed of the laser probe and the temperature of the workpiece surface, providing an accurate data basis for the stable control of laser pulse energy.

[0075] According to an embodiment of the present invention, in step S104, the first area of ​​the light spot on the workpiece surface, the size of the area to be processed on the workpiece surface, the preset processing time and the preset processing temperature are obtained. Before the processing of the workpiece begins, the first area of ​​the light spot on the workpiece surface (i.e., the area of ​​the light spot formed by the laser beam emitted by the laser probe on the workpiece surface), the size of the area to be processed on the workpiece surface (i.e., the length and width of the area to be processed), the preset processing time and the preset processing temperature are obtained.

[0076] According to an embodiment of the present invention, in step S105, the working moving speed and working power of the laser probe when surface treatment is performed on the area to be processed on the surface of the workpiece are determined according to the first area of ​​the light spot on the surface of the workpiece, the size of the area to be processed on the surface of the workpiece, the preset processing time, the preset processing temperature and the control function, including: determining the length of the processing path of the light spot in the area to be processed on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece; determining the constraints of the optimization model according to the length of the processing path, the preset processing time, the preset processing temperature and the control function; determining the objective function of the optimization model according to the length of the processing path and the preset processing time; solving the optimization model according to the constraints and objective function of the optimization model to obtain the working moving speed and working power of the laser probe.

[0077] According to an embodiment of the present invention, the length of the processing path of the area to be processed by the light spot on the surface of the workpiece is determined according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece. For example, the shape of the workpiece may be a cuboid. Figure 2 A schematic diagram exemplarily shows a workpiece according to an embodiment of the present invention, Figure 3 A schematic diagram exemplarily shows two adjacent rows of processing paths of laser spots according to an embodiment of the present invention, Figure 2 The solid rectangle in the figure represents the area to be processed of the workpiece. The area surrounded by the dotted line inside the area to be processed of the workpiece represents the area swept by the laser spot when it moves along a straight line. This area will be heated by the laser. To ensure that the laser spot processes the area to be processed comprehensively, Figure 3 As shown, after the laser spot moves on two adjacent processing paths, the areas swept by overlap to a certain extent. Then, according to the length of the processing path, the preset processing time, the preset processing temperature and the control function, the constraint conditions of the optimization model and the objective function of the optimization model can be determined, and then the optimization model can be solved to obtain the working moving speed and working power of the laser probe, and improve the control accuracy of the laser pulse energy, wherein the optimization model can be a nonlinear programming model or a genetic algorithm model, and the present invention does not set any limitation on this.

[0078] According to an embodiment of the present invention, determining the length of a processing path of the light spot in the area to be processed on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece includes: determining the length and width of the area to be processed according to the size of the area to be processed; determining the length L of the processing path of the light spot in the area to be processed on the surface of the workpiece according to formula (2),

[0079]

[0080] Among them, l is the length of the area to be processed, w is the width of the area to be processed, S 1 is the first area, k is the overlapping ratio of two adjacent rows of paths of the light spot, and roundup is the upward rounding function.

[0081] According to an embodiment of the present invention, assuming that the upper surface of the workpiece is the area to be processed, the processing method of the area to be processed on the surface of the workpiece is as follows: Figure 2 As shown, the lengths of the left and right sides of the solid rectangle can represent the width w of the area to be processed, and the lengths of the upper and lower sides of the solid rectangle can represent the length l of the area to be processed. It is assumed that the light spot needs to be swept once in the length direction of the area to be processed of the workpiece, and then immediately moves in the width direction. After moving in the width direction, it is swept again in the length direction, and this is repeated n-1 times, that is, it is swept n times in the length direction to complete the workpiece processing (that is, the light spot needs to be swept n times in the length direction to complete the workpiece processing. In other words, after each switching of the processing path, it moves in the length direction of the area to be processed. After switching the processing path n-1 times and sweeping n times in the length direction, the area swept by the light spot can cover the area to be processed). Since the shape of the light spot is circular, S 1 is the first area of ​​the light spot on the workpiece surface, can be expressed as the diameter of the light spot, so, It can represent the sum of the widths of the tracks caused by the light spot moving on the area to be processed. The sum of the widths minus the overlap width of the tracks caused by the light spot moving on the area to be processed can be used to obtain the total width of all areas swept by the light spot after multiple switching of the processing path. The total width is equal to the width of the area to be processed. When the light spot switches the processing path n times, (n-1) overlap areas will be generated. k is the overlap ratio of two adjacent rows of the light spot path, that is, the ratio of the overlap width to the light spot diameter. Therefore, It can represent the total width of the overlapping area caused by the movement of the light spot on the area to be processed, that is, the above-mentioned overlapping width. Therefore, the width of the area to be processed can be obtained Then we can get In order to ensure that the area swept by the light spot covers the area to be processed without omission, the formula can be rounded up to obtain the number of times the light spot needs to be swept along the length direction. Then, the length L of the processing path of the light spot in the area to be processed on the surface of the workpiece is determined by multiplying the number of times the light spot needs to be scanned along the length direction by the length of the area to be processed.

[0082] In this way, the size information of the area to be processed of the workpiece can be obtained, and the number of times the laser switches the processing path on the area to be processed can be determined based on the width of the area to be processed, the first area of ​​the light spot on the surface of the workpiece, and the overlap of the trajectory caused by the light spot moving on the area to be processed. Then, combined with the length of the area to be processed, the length of the processing path of the light spot in the area to be processed on the surface of the workpiece is determined. The calculation error is reduced by rounding up the function, so that the length of the processing path of the laser probe is accurately calculated, thereby improving the working efficiency of the laser probe.

[0083] According to an embodiment of the present invention, determining the constraint conditions of the optimization model according to the length of the processing path, the preset processing time, the preset processing temperature and the control function includes: determining the constraint conditions of the optimization model according to formula (3), formula (4), formula (5), formula (6) and formula (7),

[0084]

[0085] (1-σ)T p ≤T E ≤(1+σ)T p (5)

[0086] P w ≤P max (6)

[0087] v w ≤v max (7)

[0088] Among them, L is the length of the moving path of the light spot in the area to be processed on the surface of the workpiece, w is the width of the area to be processed, S 1 is the first area, k is the overlap ratio of two adjacent lines of the spot, roundup is the upward rounding function, v p is the preset moving speed, v w is the unknown value of the working moving speed, ΔT p is the preset processing time, P w is the undetermined value of the working power, T E To estimate the processing temperature, T p is the preset processing temperature, σ is the preset proportionality coefficient, P max is the maximum power of the laser probe, v max is the maximum moving speed of the laser probe, α 1,F is α 1 The solution value of α 2,F is α 2 The solution value of α 3,F is α 3 The solution value of α 4,F is α 4The solution value of α 5,F is α 5 The solution value of .

[0089] According to the embodiment of the present invention, as described above, It can represent the number of times the light spot switches the processing path on the workpiece to be processed. Therefore, in formula (3), It indicates the number of times the laser probe needs to switch the processing path after the processing starts. It can be expressed as That is, the difference between the diameter of the light spot and the width of the overlapping part of the two tracks indicates the distance the laser probe needs to move each time it switches the processing path. It can represent the total distance that the laser probe needs to move along the width direction when switching the processing path during the processing. It can represent the time required for the laser probe to switch the processing path during the entire processing process. It can be expressed as the time required for the light spot to move on the processing path in the area to be processed on the surface of the workpiece. The sum of the two can represent the total time required for processing the workpiece, and make it less than or equal to the preset processing time ΔT p , the processing time is set by comprehensively considering the size of the workpiece and the movement mode of the laser probe, so that the calculation of the time required for the laser probe to process the workpiece is more accurate.

[0090] According to an embodiment of the present invention, by solving the first undetermined coefficient equation, the solution value of the undetermined coefficient is obtained, and the solution value of the undetermined coefficient is brought into formula (4), so that formula (4) can accurately express the relationship between the estimated processing temperature and the undetermined value of the working power and the undetermined value of the working moving speed, thereby accurately controlling the average temperature of the light spot on the trajectory of the moving area to be processed through the undetermined value of the working power and the undetermined value of the working moving speed of the laser probe, that is, the estimated processing temperature. In formula (5), (1-σ)T p ≤T E ≤(1+σ)T p It can be indicated that the error between the preset processing temperature and the estimated processing temperature should be kept within a preset ratio. For example, the preset proportionality coefficient σ can be set to 0.05, which means that the difference between the preset processing temperature and the estimated processing temperature is ±5%. Formula (6) can be indicated that the undetermined value of the working power should be lower than or equal to the maximum power of the laser probe. Formula (7) can be indicated that the undetermined value of the working moving speed should be lower than or equal to the maximum moving speed of the laser probe.

[0091] According to an embodiment of the present invention, determining the objective function of the optimization model according to the length of the moving path and the preset processing time includes: determining the objective function of the optimization model according to formula (8),

[0092]

[0093] Among them, min is the minimization function.

[0094] According to an embodiment of the present invention, It can represent the time required for the laser probe to process the workpiece, so The electric energy consumed by the laser probe to process the workpiece can be represented. The adjustment mode optimization model can be solved by the constraints of the optimization model determined above and the objective function of the optimization model. The objective function can minimize the electric energy consumed by the laser probe to process the workpiece, so that the laser probe can complete the processing within the preset processing time and complete the processing with the minimum energy consumption when the area to be processed reaches the preset processing temperature. The optimization model can be a nonlinear programming model, a genetic algorithm model, etc., and can solve the optimal solution of the undetermined value of the working power and the undetermined value of the working moving speed, so as to obtain the optimal solution of the working power and the working moving speed, and then process the workpiece, thereby improving the accuracy of laser pulse energy control.

[0095] In this way, the time required for the laser probe to process the workpiece can be determined by the distance the laser probe needs to move to switch the processing path, the length of the processing path, and the working moving speed of the laser probe. The processing temperature of the area to be processed can be determined based on the estimated processing temperature and the relationship between the working power and moving speed of the laser probe. Then, combined with the rated parameters of the laser probe, various factors are comprehensively considered, constraints are set in a targeted manner, and the objective function of the optimization model is determined, so that the laser probe can complete the processing within the preset processing time and complete the processing with the minimum energy consumption when the area to be processed reaches the preset processing temperature, thereby improving the control accuracy of the laser pulse energy, reducing the energy consumption of the laser probe, and improving the working efficiency of the laser probe.

[0096] According to an embodiment of the present invention, in step S106, the laser probe is controlled to perform surface treatment on the area to be processed on the surface of the workpiece according to the working moving speed and the working power. That is, according to the constraint conditions of the optimization model determined above and the objective function of the optimization model, the best solution for the operation of the laser probe is determined, and then the laser probe is controlled to perform surface treatment on the area to be processed on the surface of the workpiece.

[0097] According to a laser pulse energy control method for surface treatment according to an embodiment of the present invention, the movement of the laser probe can be controlled within a test cycle so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple moments, and the first temperature data of multiple positions on the trajectory of the light spot moving between adjacent moments are measured by an infrared camera, and then the control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe is determined, so that the relationship between the moving speed and power of the laser probe and the temperature of the workpiece surface can be accurately described, and the first area of ​​the light spot on the workpiece surface, the size of the area to be processed on the workpiece surface, the preset processing time and the preset processing temperature can be obtained, and then the working moving speed and working power of the laser probe are determined in combination with the control function, so as to control the laser probe to perform surface treatment on the area to be processed on the workpiece surface, and comprehensively consider various factors to reasonably set the power and moving speed of the laser probe to improve the control accuracy of the laser pulse energy. When determining the control function, the first undetermined coefficient equation can be constructed according to the positive correlation between the average temperature of each position in the trajectory of the light spot movement and the power of the laser probe and the inverse correlation between the average temperature of each position in the trajectory of the light spot movement and the moving speed of the laser probe, and the solution value of the first undetermined coefficient that minimizes the overall error can be obtained, and then the control function that can adapt to the current environment and the current batch of workpiece materials can be determined to accurately describe the relationship between the power and moving speed of the laser probe and the temperature of the workpiece surface, and provide an accurate data basis for the stable control of the laser pulse energy. When determining the length of the processing path, the size information of the area to be processed of the workpiece can be obtained, and the number of times the laser switches the processing path on the area to be processed is determined according to the width of the area to be processed, the first area of ​​the light spot on the surface of the workpiece, and the overlap of the trajectory caused by the light spot moving on the area to be processed, and then the length of the processing path of the light spot on the surface of the workpiece to be processed is determined in combination with the length of the area to be processed, and the calculation error is reduced by rounding up the function, so as to accurately calculate the length of the processing path of the laser probe, thereby improving the working efficiency of the laser probe. When determining the working power and the working moving speed, the time required for the laser probe to process the workpiece can be determined by the distance the laser probe needs to move to switch the processing path, the length of the processing path, and the working moving speed of the laser probe. The processing temperature of the area to be processed is determined based on the estimated processing temperature and the relationship between the working power and the moving speed of the laser probe. Then, combined with the rated parameters of the laser probe, various factors are comprehensively considered, constraints are set in a targeted manner, and the objective function of the optimization model is determined, so that the laser probe can complete the processing within the preset processing time and make the area to be processed reach the preset processing temperature, and complete the processing work with the minimum energy consumption, thereby improving the control accuracy of the laser pulse energy, reducing the energy consumption of the laser probe, and improving the working efficiency of the laser probe.

[0098] Figure 4 A schematic diagram of a laser pulse energy control system for surface treatment according to an embodiment of the present invention is exemplarily shown, the system comprising:

[0099] A first control module controls the laser probe to move above the workpiece surface during a test cycle so that the laser spot moves on the workpiece surface, and changes the power and moving speed of the laser probe at multiple times during the test cycle;

[0100] a temperature data determination module, which measures, by means of an infrared camera, at the i+1th moment in a test cycle, first temperature data of a plurality of positions on a trajectory where the light spot moves within a time interval between the i-th moment and the i+1th moment, wherein i is a positive integer;

[0101] A control function determination module, which determines a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments and the moving speed of the laser probe at multiple moments;

[0102] A first acquisition module is used to acquire a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature;

[0103] A first determination module determines, according to a first area of ​​the light spot on the workpiece surface, a size of the to-be-processed area on the workpiece surface, a preset processing time, a preset processing temperature, and the control function, a working moving speed and a working power of the laser probe when performing surface treatment on the to-be-processed area on the workpiece surface;

[0104] The second control module controls the laser probe to perform surface treatment on the to-be-processed area on the surface of the workpiece according to the working moving speed and the working power.

[0105] The present invention may be a method, an apparatus, a system and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing various aspects of the present invention.

[0106] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A laser pulse energy control method for surface treatment, characterized in that: include: During the test cycle, the laser probe is controlled to move above the surface of the workpiece so that the laser spot moves on the surface of the workpiece, and the power and moving speed of the laser probe are changed at multiple times during the test cycle; By means of an infrared camera, at the i+1th moment in the test cycle, first temperature data of a plurality of positions on the trajectory of the light spot moving within the time interval between the i-th moment and the i+1-th moment are measured, wherein i is a positive integer; Determine a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments; Acquire a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature; Determine the working moving speed and working power of the laser probe when performing surface treatment on the area to be processed on the surface of the workpiece according to the first area of ​​the light spot on the surface of the workpiece, the size of the area to be processed on the surface of the workpiece, the preset processing time, the preset processing temperature and the control function; According to the working moving speed and the working power, the laser probe is controlled to perform surface treatment on the to-be-processed area on the surface of the workpiece.

2. The laser pulse energy control method for surface treatment according to claim 1, characterized in that: Determining a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments, and the moving speed of the laser probe at multiple moments, including: Determine a first average temperature of the trajectory where the light spot moves within the time interval between the i-th moment and the i+1-th moment according to first temperature data of a plurality of positions on the trajectory where the light spot moves within the time interval between the i-th moment and the i+1-th moment; The control function is determined according to the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment.

3. The laser pulse energy control method for surface treatment according to claim 2, characterized in that: Determining the control function according to a first average temperature of a trajectory of the light spot moving in a time interval between the i-th moment and the i+1-th moment, the power of the laser probe at the i-th moment, and the moving speed of the laser probe in a time interval between the i-th moment and the i+1-th moment, comprises: According to the formula Determine the first undetermined coefficient equation, where T 1,(i)-(i+1) is the first average temperature of the trajectory of the light spot moving in the time interval between the i-th moment and the i+1-th moment, P i is the power of the laser probe at the i-th moment, v i is the moving speed of the laser probe in the time interval between the i-th moment and the i+1-th moment, α1, α2, α3, α4 and α5 are the first unknown coefficients; Solving the first undetermined coefficient according to the first average temperature of the trajectory of the light spot moving in multiple time intervals, the power of the laser probe at multiple moments, and the moving speed of the laser probe in multiple time intervals to obtain a solution value of the first undetermined coefficient; The control function is determined according to the solved value of the first undetermined coefficient and the first undetermined coefficient equation.

4. The laser pulse energy control method for surface treatment according to claim 3, characterized in that: According to the first area of ​​the light spot on the workpiece surface, the size of the to-be-processed area on the workpiece surface, the preset processing time, the preset processing temperature and the control function, the working moving speed and working power of the laser probe when performing surface treatment on the to-be-processed area on the workpiece surface are determined, including: Determine the length of a processing path of the light spot in the area to be processed on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece; Determining the constraint conditions of the optimization model according to the length of the processing path, the preset processing time, the preset processing temperature and the control function; Determining an objective function of an optimization model according to the length of the processing path and the preset processing time; The optimization model is solved according to the constraint conditions and objective function of the optimization model to obtain the working moving speed and working power of the laser probe.

5. The laser pulse energy control method for surface treatment according to claim 4, characterized in that: Determining the length of a processing path of the light spot in the area to be processed on the surface of the workpiece according to the size of the area to be processed and the first area of ​​the light spot on the surface of the workpiece, comprising: Determine the length and width of the area to be processed according to the size of the area to be processed; According to the formula Determine the length L of the processing path of the light spot in the area to be processed on the surface of the workpiece, where l is the length of the area to be processed, w is the width of the area to be processed, S1 is the first area, k is the overlap ratio of two adjacent rows of paths of the light spot, and roundup is an upward rounding function.

6. The laser pulse energy control method for surface treatment according to claim 4, characterized in that: Determining the constraint conditions of the optimization model according to the length of the processing path, the preset processing time, the preset processing temperature and the control function includes: According to the formula (1-σ)T p ≤T E ≤(1+σ)T p P w ≤P max in w ≤in max Determine the constraints of the optimization model, where L is the length of the moving path of the light spot in the area to be processed on the surface of the workpiece, w is the width of the area to be processed, S1 is the first area, k is the overlap ratio of two adjacent lines of the light spot, roundup is the upward rounding function, and v p is the preset moving speed, v w is the unknown value of the working moving speed, ΔT p is the preset processing time, P w is the undetermined value of the working power, T E To estimate the processing temperature, T p is the preset processing temperature, σ is the preset proportional coefficient, P max is the maximum power of the laser probe, v max is the maximum moving speed of the laser probe, α 1,F is the solution value of α1, α 2,F is the solution value of α2, α 3,F is the solution value of α3, α 4,F is the solution value of α4, α 5,F is the solution value of α5.

7. The laser pulse energy control method for surface treatment according to claim 6, characterized in that: According to the length of the moving path and the preset processing time, determining the objective function of the optimization model includes: According to the formula Determine the objective function of the optimization model, where min is the minimization function.

8. A laser pulse energy control system for surface treatment, characterized in that: include: A first control module controls the laser probe to move above the workpiece surface during a test cycle so that the laser spot moves on the workpiece surface, and changes the power and moving speed of the laser probe at multiple times during the test cycle; a temperature data determination module, which measures, by means of an infrared camera, at the i+1th moment in a test cycle, first temperature data of a plurality of positions on a trajectory where the light spot moves within a time interval between the i-th moment and the i+1th moment, wherein i is a positive integer; A control function determination module, which determines a control function between the temperature of the light spot on the trajectory between adjacent moments and the power and moving speed of the laser probe according to the first temperature data, the power of the laser probe at multiple moments and the moving speed of the laser probe at multiple moments; A first acquisition module is used to acquire a first area of ​​the light spot on the workpiece surface, a size of a to-be-processed area on the workpiece surface, a preset processing time, and a preset processing temperature; A first determination module determines, according to a first area of ​​the light spot on the workpiece surface, a size of the to-be-processed area on the workpiece surface, a preset processing time, a preset processing temperature, and the control function, a working moving speed and a working power of the laser probe when performing surface treatment on the to-be-processed area on the workpiece surface; The second control module controls the laser probe to perform surface treatment on the to-be-processed area on the surface of the workpiece according to the working moving speed and the working power.

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