Control method, controller and system for monitoring and adjusting laser processing

Abstract

The present invention provides a control method, controller, and system for monitoring and adjusting laser processing. The control method includes acquiring at least two target images captured by an image acquisition device, wherein the at least two target images include an image containing illumination light and an image without illumination light of a laser action area at the same moment; determining processing offset information based on the at least two target images, wherein the processing offset information characterizes the offset of the actual position of the laser focus relative to the desired position during laser processing; and controlling the operating parameters of the laser based on the processing offset information, wherein the operating parameters include at least one of the following: the intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus; the image containing illumination light and the image without illumination light of the laser action area at the same moment can be simultaneously obtained, the algorithm is simple and the accuracy is high, and real-time monitoring and closed-loop adjustment of the laser focus position are achieved.

Description

Technical Field

[0001] The present invention relates to the field of laser processing, and in particular to a control method, a controller and a system for monitoring and adjusting laser processing. Background Art

[0002] During laser processing, the position of the laser focus relative to the nozzle and workpiece can affect cutting quality. Especially during oxygen-assisted carbon steel cutting, an inappropriate focus position can affect the kerf width used for slag removal or the coaxiality between the high-energy laser beam and the assist gas, leading to rough sections, burrs, slag, and inconsistent edges. During high-power laser cutting, as processing time increases, the amount of heat absorbed and accumulated by components such as the lens and lens barrel continues to increase. The lens's inherent "thermal lens effect" and deformation of the lens barrel caused by uneven heating can cause changes in the focus position, affecting cutting quality.

[0003] In the prior art, the following methods are used to monitor images of the processing area:

[0004] 1) Pulse interval illumination is used to acquire images of the processing area. Image sequences with and without illumination are acquired at intervals. After software registration, analysis is performed. The pulse illumination, acquisition, and registration control procedures are complex, and the sampling frame rate is reduced, resulting in image asynchrony.

[0005] 2) Using devices such as dichroic mirrors and hollow reflectors, the collected process radiation is divided into multiple paths according to wavelength, and synchronous collection is achieved through multiple cameras or sensor arrays. This is costly and difficult to match data between different cameras. Summary of the Invention

[0006] The present invention provides a control method, a controller and a system for monitoring and adjusting laser processing, so as to solve the problems of complex algorithms and low precision.

[0007] According to a first aspect of the present invention, there is provided a control method for monitoring and adjusting laser processing, comprising:

[0008] Acquire at least two target images captured by an image acquisition device, wherein the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment;

[0009] Determining processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of a laser focus relative to a desired position during laser processing;

[0010] According to the processing offset information, the operating parameters of the laser are controlled, and the operating parameters include at least one of the following:

[0011] The intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus.

[0012] Optionally, the illumination light image includes:

[0013] a pixel portion representing the nozzle profile;

[0014] Characterize the pixel portion of the melt pool;

[0015] The unilluminated image includes:

[0016] Characterizes the pixel portion of the melt pool.

[0017] Optionally, determining processing offset information according to the at least two target images includes:

[0018] Determining, based on the at least two target images, nozzle contour information of the nozzle and molten pool contour information of the molten pool; the nozzle contour information represents positions of pixel points of the nozzle contour in an image coordinate system, and the molten pool contour information represents positions of pixel points of the molten pool contour in the image coordinate system;

[0019] The machining offset information is determined according to the nozzle profile information and the molten pool profile information.

[0020] Optionally, determining the nozzle profile information of the nozzle and the molten pool profile information of the molten pool according to the at least two target images includes:

[0021] Determining the nozzle contour information in the illumination light-containing image according to the grayscale value of each pixel in the illumination light-containing image and the pixel threshold corresponding to the nozzle contour;

[0022] The molten pool contour information is determined in the non-illuminated light image according to the grayscale value of each pixel in the non-illuminated light image and the pixel threshold corresponding to the molten pool contour.

[0023] Optionally, the processing offset information includes processing plane offset information;

[0024] Determining the machining offset information according to the nozzle profile information and the molten pool profile information specifically includes:

[0025] Determining nozzle center information according to the nozzle contour information, wherein the nozzle center information represents a position of a center of the nozzle contour in the image coordinate system;

[0026] Determining laser focus information based on the molten pool contour information, wherein the laser focus information represents the position of the laser focus in the image coordinate system;

[0027] The processing offset information is determined according to the nozzle center information and the laser focus information.

[0028] Optionally, the processing offset information includes height offset information;

[0029] Determining the machining offset information according to the nozzle profile information and the molten pool profile information specifically includes:

[0030] Determining the width of the molten pool according to the molten pool profile information;

[0031] The processing offset information is determined according to the width information.

[0032] Optionally, after determining the nozzle profile information of the nozzle and the molten pool profile information of the molten pool according to the at least two target images, the method further includes:

[0033] Nozzle status information is determined based on the nozzle profile information, where the nozzle status information represents a damage condition of the nozzle.

[0034] Optionally, the control system for monitoring and adjusting laser processing further includes:

[0035] The nozzle replacement is triggered according to the nozzle status information.

[0036] According to a second aspect of the present invention, there is provided a control system for monitoring and adjusting laser processing, comprising an image acquisition device, a laser cutting head, an illumination light source, and a host computer, wherein the laser cutting head is configured to be directly or indirectly controlled by the host computer;

[0037] The illumination light source is used to continuously supplement the image of the laser action area with illumination light;

[0038] The laser cutting head is used to output a processing laser through a nozzle to perform laser processing on the object to be processed;

[0039] The image acquisition device is a multi-channel image acquisition device, which is used to acquire images of the laser action area to form at least two target images and feed them back to the host computer. The at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment;

[0040] The host computer is used to execute the control method involved in the first aspect and its optional solutions.

[0041] Optionally, the laser cutting head includes a collimating lens and a focusing lens arranged inside the housing, the focusing lens is arranged between the nozzle and the collimating lens, and the nozzle is arranged at one end of the housing close to the object to be processed;

[0042] The collimating mirror is used to collimate the received initial laser to obtain parallel initial laser, and transmit the parallel initial laser to the focusing mirror;

[0043] The focusing mirror is used to focus the received parallel initial laser light to obtain a focused initial laser light, and transmit the focused initial laser light to the nozzle;

[0044] The nozzle is used to transmit the received focused initial laser light out of the laser cutting head to obtain the processing laser light, and transmit the processing laser light to the laser action area.

[0045] Optionally, a lower protective mirror is further provided in the housing of the laser cutting head, and the lower protective mirror is provided between the focusing mirror and the nozzle to receive the focused initial laser and transmit it to the nozzle.

[0046] Optionally, the laser cutting head further comprises a dichroic mirror,

[0047] The angle between the dichroic mirror and the surface of the object to be processed is a first angle; the dichroic mirror is used for allowing the initial laser in the laser cutting head to pass through;

[0048] The dichroic mirror is also used to reflect the first image capture beam to form a second image capture beam, and transmit the second image capture beam to the image capture device; the first image capture beam is an image of the laser action area captured, and the first image capture beam coincides with at least part of the initial laser.

[0049] Optionally, the control system for monitoring and adjusting laser processing also includes a reflecting device, which is arranged between the dichroic mirror and the image acquisition device, and is used to change the optical path of the second image acquisition light beam, obtain the second image acquisition light beam with a changed optical path, and transmit the second image acquisition light beam with a changed optical path to the image acquisition device.

[0050] Optionally, the control system for monitoring and adjusting laser processing further includes a beam combiner, which is used to combine the illumination light with the first image acquisition light beam or the second image acquisition light beam.

[0051] Optionally, the image acquisition device includes N filters, lenses, and N imaging units, at least one filter can filter out the illumination light, wherein N ≥ 2;

[0052] A filter is provided between the lens and each imaging unit, and the lens is used to transmit the received second image acquisition light beam to the filter;

[0053] The filter is used to filter the light beam of the corresponding frequency band in the received second image acquisition light beam to obtain a target image light beam, and transmit the target image light beam to the corresponding imaging unit;

[0054] The imaging unit is communicatively connected to the host computer, and is used for converting the target image light beam into a corresponding target image, and feeding the obtained target image back to the host computer.

[0055] According to a third aspect of the present invention, there is provided a controller for monitoring and adjusting laser processing, comprising:

[0056] An image acquisition module acquires at least two target images acquired by an image acquisition device, wherein the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment;

[0057] a data processing module, configured to determine processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of a laser focus relative to a desired position during laser processing;

[0058] A parameter adjustment module is used to control the operating parameters of the laser according to the processing offset information, and the operating parameters include at least one of the following:

[0059] The intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus.

[0060] According to a fourth aspect of the present invention, there is provided an electronic device comprising a processor and a memory,

[0061] The memory is used to store codes and related data;

[0062] The processor is used to execute the code in the memory to perform the method described in the first aspect of the present invention and its optional solutions.

[0063] According to a fifth aspect of the present invention, there is provided a storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect of the present invention and its optional solutions.

[0064] The control method, controller, and system for monitoring and adjusting laser processing provided by the present invention can simultaneously obtain an image of the laser action area with and without illumination at the same moment. Without the need for pulsed illumination, target images of the laser action area containing different information at the same moment can be obtained. The target images are synchronized, enabling real-time monitoring and closed-loop adjustment of the laser focus position. The algorithm is simple and highly accurate.

[0065] The image acquisition device adopts a multi-channel image acquisition device, which does not require additional optical devices for splitting light, nor does it require multiple image acquisition devices. It can obtain multiple target images at the same time, with low cost and simple system. Its imaging range does not need to be reduced, and there is no need for data matching between different image acquisition devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0067] Figure 1 This is a flow chart of a control method for monitoring and adjusting laser processing in one embodiment of the present invention. Figure 1 ;

[0068] Figure 2a An embodiment of the present invention includes an illumination light image;

[0069] Figure 2b is an image without illumination light in one embodiment of the present invention;

[0070] Figure 3 This is a flow diagram of step S102 in one embodiment of the present invention. Figure 1 ;

[0071] Figure 4 1 is a flow chart of step S1021 in one embodiment of the present invention;

[0072] Figure 5 This is a flow diagram of step S1022 in one embodiment of the present invention. Figure 1 ;

[0073] Figure 6a This is a schematic diagram of the characteristic quantity of the laser action area in one embodiment of the present invention. Figure 1 ;

[0074] Figure 6b Schematic diagram 2 of characteristic quantities of the laser action area in one embodiment of the present invention;

[0075] Figure 6c This is a schematic diagram of the characteristic quantity of the laser action area in one embodiment of the present invention. Figure 3 ;

[0076] Figure 6d This is a schematic diagram of the characteristic quantity of the laser action area in one embodiment of the present invention. Figure 4 ;

[0077] Figure 72 is a flow chart of step S1022 in one embodiment of the present invention;

[0078] Figure 8 2 is a flow chart of step S102 in one embodiment of the present invention;

[0079] Figure 9 FIG2 is a second flow chart of a control method for monitoring and adjusting laser processing according to an embodiment of the present invention;

[0080] Figure 10 This is a schematic diagram of the structure of a control system for monitoring and adjusting laser processing in one embodiment of the present invention. Figure 1 ;

[0081] Figure 11 2 is a structural diagram of a control system for monitoring and adjusting laser processing in one embodiment of the present invention;

[0082] Figure 12 Schematic diagram of a control system for monitoring and adjusting laser processing in one embodiment of the present invention Figure 1 ;

[0083] Figure 13 Schematic diagram 2 of a control system for monitoring and adjusting laser processing according to an embodiment of the present invention;

[0084] Figure 14 Schematic diagram of a control system for monitoring and adjusting laser processing in one embodiment of the present invention Figure 3 ;

[0085] Figure 15 Schematic diagram of a control system for monitoring and adjusting laser processing in one embodiment of the present invention Figure 4 ;

[0086] Figure 16 Schematic diagram of a control system for monitoring and adjusting laser processing in one embodiment of the present invention Figure 5 ;

[0087] Figure 17 This is a schematic diagram of a program module of a controller for monitoring and adjusting laser processing in one embodiment of the present invention. Figure 1 ;

[0088] Figure 18 Schematic diagram 2 of a program module of a controller for monitoring and adjusting laser processing in one embodiment of the present invention;

[0089] Figure 19 This is a schematic diagram of a program module of a controller for monitoring and adjusting laser processing in one embodiment of the present invention. Figure 3 ;

[0090] Figure 20FIG. 1 is a schematic diagram of the structure of an electronic device in one embodiment of the present invention. DETAILED DESCRIPTION

[0091] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0092] The terms "first," "second," "third," "fourth," and so on (if any) in the description and claims of the present invention and in the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in orders other than those illustrated or described herein. In addition, the terms "including" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such processes, methods, products, or apparatuses.

[0093] The following specific embodiments are used to describe the technical solution of the present invention in detail. 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.

[0094] Please refer to Figure 1 , control methods for monitoring and adjusting laser processing, including:

[0095] S101: Acquire at least two target images captured by an image acquisition device,

[0096] S102: Determine processing offset information based on the at least two target images.

[0097] S103: Controlling the laser operating parameters according to the processing offset information;

[0098] Among them, the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment. It can be further understood that the at least two target images are images of the same area at the same moment, and the main difference between them is whether they contain illumination light.

[0099] The image acquisition device is a multi-channel image acquisition device, wherein the operating frequency band of at least one channel matches the frequency band of the illumination light, and simultaneously acquires the melt pool image and the melt pool edge and the nozzle to obtain an image containing the illumination light. At least one channel can filter out the illumination light, retaining only the melt pool image, to obtain an image without the illumination light.

[0100] Each channel of the image acquisition device can filter out light of the corresponding frequency band. Under the condition of continuous illumination, without reducing the acquisition frame rate or adding additional spectroscopic components, the target image obtained by each channel can contain different information of the laser action area. There is no need to use pulsed illumination. The target image is synchronized, realizing real-time monitoring and closed-loop adjustment of the laser focus position. The algorithm is simple and the accuracy is high.

[0101] The processing offset information characterizes the offset of the actual position of the laser focus relative to the required position during laser processing. For example, the offset of the laser focus on the surface of the object to be processed will affect the accuracy of the laser processing position and the quality of the nozzle. For example, the offset of the laser focus in the height direction will affect the width of the slit formed by laser processing, thereby affecting the accuracy of laser processing.

[0102] The operating parameters include at least one of the following:

[0103] The intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus.

[0104] In step S103, the control of the working parameters may be automatic control by the host computer to adjust the working parameters, or the host computer may issue corresponding warning instructions to manually control the working parameters.

[0105] Please refer to Figure 2a and Figure 2b In one embodiment, the illumination light image includes:

[0106] a pixel portion 52 representing the nozzle profile;

[0107] a pixel portion 51 representing the melt pool;

[0108] The unilluminated image includes:

[0109] Pixel portion 51 representing the melt pool.

[0110] Figure 2aThe image includes a pixel portion 51 representing the molten pool, a pixel portion 52 representing the nozzle contour, a pixel portion 251 representing the surface of the object to be processed, and a pixel portion 511 representing the molten pool contour. The pixel portion 511 representing the molten pool contour can also be understood as a pixel portion representing the kerf edge formed during the laser processing process. Figure 2b Corresponding to the image without illumination, a more accurate melt pool contour can be obtained.

[0111] Please refer to Figure 3 In one embodiment, step S102 includes:

[0112] S1021: Determining nozzle profile information of the nozzle and molten pool profile information of the molten pool according to the at least two target images;

[0113] S1022: Determine the machining offset information according to the nozzle profile information and the molten pool profile information;

[0114] The nozzle contour information represents the position of the pixel points of the nozzle contour in the image coordinate system, and the molten pool contour information represents the position of the pixel points of the molten pool contour in the image coordinate system.

[0115] In one example, the nozzle contour information and the molten pool contour information of the molten pool can be obtained from the image containing illumination light, and the processing offset information can be determined based on the obtained nozzle contour information and the molten pool contour information of the molten pool; in another example, the nozzle contour information can be obtained from the image containing illumination light, and the molten pool contour information can be obtained from the image without illumination light, and then the processing offset information can be determined based on the obtained nozzle contour information and the molten pool contour information of the molten pool.

[0116] Please refer to Figure 4 In one embodiment, step S1021 includes:

[0117] S10211: Determine the nozzle contour information in the image containing illumination light according to the grayscale value of each pixel in the image containing illumination light and the pixel threshold corresponding to the nozzle contour;

[0118] S10212: Determine the molten pool contour information in the non-illuminated image according to the grayscale value of each pixel point in the non-illuminated image and the pixel threshold corresponding to the molten pool contour.

[0119] In one example, the target image can be subjected to dynamic multi-threshold segmentation, such as the OTSU algorithm, to extract the nozzle contour and the molten pool contour in the target image and obtain the nozzle contour information and the molten pool contour information.

[0120] Please refer to Figures 5 to 7In one embodiment, the processing offset information includes processing plane offset information; the processing plane offset information represents the offset direction and offset amount of the laser focus on the surface of the object to be processed relative to the nozzle.

[0121] Step S1022 specifically includes:

[0122] S10221: Determine nozzle center information according to the nozzle contour information, where the nozzle center information represents a position of a center of the nozzle contour in the image coordinate system;

[0123] S10222: Determine laser focus information based on the molten pool contour information, where the laser focus information represents a position of the laser focus in the image coordinate system;

[0124] S10223: Determine the processing offset information based on the nozzle center information and the laser focus information.

[0125] In one example, the obtained nozzle contour information is subjected to circle fitting to obtain the nozzle center information; based on the obtained molten pool contour information, the center line of the molten pool is determined, and then the laser focus information is determined; further, based on the nozzle center information and the laser focus information, the processing plane offset information is obtained.

[0126] In one embodiment, the processing offset information includes height offset information; the height offset information represents the offset direction and offset amount of the laser focus in the height direction;

[0127] Step S1022 specifically includes:

[0128] S10224: Determine the width of the molten pool according to the molten pool profile information;

[0129] S10225: Determine the processing offset information based on the width information.

[0130] In one example, the width of the molten pool is calculated based on the obtained molten pool contour information, and the calculated molten pool width is compared with the preset molten pool width information. The height offset information is determined by combining the corresponding relationship between the molten pool width and the laser focus height in the database;

[0131] In another example, based on the obtained molten pool contour information, multiple different width information of the molten pool are calculated, and based on the change in the width of the molten pool, the height offset information is calculated.

[0132] Please refer to Figure 6aIn one embodiment, when the position O' of the laser focus in the image coordinate system matches the position O of the nozzle center in the image coordinate system, the laser focus is not offset relative to the nozzle. At this time, the width of the slit edge formed is d. The height offset information of the laser focus can be determined by comparing the size relationship between d and the preset slit width.

[0133] Please refer to Figure 6b In one embodiment, the slit width changes at different times, and the height offset information of the laser focus can be determined by calculating the change relationship between the two slit widths d and d';

[0134] Please refer to Figure 6c Different from the above embodiments, when the obtained molten pool contour information includes two non-parallel cutting paths, the center line I corresponding to the molten pool 5 and the center line I' corresponding to the molten pool 5 in the image coordinate system are calculated respectively, and the intersection of the center line I and the center line I' is the position of the laser focus in the image coordinate system.

[0135] Please refer to Figure 6d In one embodiment, the position of the laser focus in the image coordinate system is O', and the position of the nozzle center in the image coordinate system is O. By calculating the offset of O' relative to O, the processing plane offset information can be obtained.

[0136] Please refer to Figure 8 In one embodiment, after step S1021, the method further includes:

[0137] S1023: Determine nozzle status information based on the nozzle profile information, where the nozzle status information represents a damage condition of the nozzle.

[0138] In the above embodiments, the damage of the nozzle can be understood as whether the nozzle is worn out due to high temperature during the initial use of the laser, thereby causing the processing laser to be mismatched with the expected processing laser, thereby affecting the quality of the laser processing;

[0139] To determine the nozzle status information, for example, circle fitting may be performed on the nozzle contour information to determine the circularity of the nozzle contour in the image coordinate system, thereby determining the nozzle status information.

[0140] Please refer to Figure 9 In one embodiment, the control system for monitoring and adjusting laser processing further comprises:

[0141] S104: triggering the replacement of the nozzle according to the nozzle status information.

[0142] In the above embodiment, the triggering method for determining whether the nozzle needs to be replaced may be, for example, performing circle fitting on the nozzle contour information to determine the circularity of the nozzle contour in the image coordinate system. If the obtained circularity is less than a preset circularity, the nozzle replacement is triggered.

[0143] As for the implementation method of triggering nozzle replacement, for example, a nozzle replacement instruction can be issued by a host computer, and the nozzle can be automatically replaced by driving a corresponding device;

[0144] For example, a nozzle replacement instruction can be issued by the host computer, and the corresponding device can output a warning message that the nozzle is damaged, and then instruct the outside to manually replace it.

[0145] Please refer to Figure 10 , a control system 2 for monitoring and adjusting laser processing, comprising an image acquisition device 22, a laser cutting head 24, an illumination light source 23 and a host computer 21, wherein the laser cutting head 24 is configured to be directly or indirectly controlled by the host computer 21;

[0146] The illumination light source 23 is used to continuously supplement the image of the laser action area with illumination light;

[0147] The laser cutting head 24 is used to output a processing laser through a nozzle 241 to perform laser processing on the object 25 to be processed;

[0148] The image acquisition device 22 is a multi-channel image acquisition device, which is used to acquire images of the laser action area, form at least two target images, and feed them back to the host computer 21. The at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment;

[0149] The host computer 21 is used for:

[0150] Acquire at least two target images captured by the image acquisition device 22;

[0151] Determining processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of a laser focus relative to a desired position during laser processing;

[0152] According to the processing offset information, the operating parameters of the laser are controlled, and the operating parameters include at least one of the following:

[0153] The intensity of the laser output by the nozzle 241 of the laser cutting head 24 and the position parameters of the laser cutting head 24 .

[0154] The position of the illumination light source 23 can be set at different positions according to needs or application environment. For example, the illumination light source 23 can be set beside the light path of the image acquisition device 22 to acquire the target image, and the illumination light passes through multiple optical devices and finally irradiates the surface of the object to be processed 25; for example, the illumination light source 23 can be set near the nozzle (for example Figure 16 The illumination light source 232 in the figure directly illuminates the surface of the object 25 to be processed.

[0155] In one example, the illumination light source 23 may be an LED light source, which can stably and evenly illuminate the entire nozzle, facilitating nozzle contour extraction. The wavelength is in the 600-670 nm band, which can match the characteristic band in the first image acquisition beam and / or the second image acquisition beam that characterizes the quality of the cutting effect. In this way, the image acquisition device 22 can simultaneously obtain nozzle contour information and molten pool contour information. The illumination power of the illumination light source 23 is 300-1000 mW, which ensures effective extraction of the nozzle and the surface features of the object to be processed, and has a similar contrast to the first image acquisition beam and / or the second image acquisition beam without causing additional heat dissipation.

[0156] The lighting source 23 in the above example can also be replaced by white light or other band LED lighting sources, or other coherent lighting sources (such as 980 nm, 808 nm, 670 nm, 532 nm, 450 nm laser lighting), which can be in the form of divergent lighting, collimated lighting, structured light lighting, etc.

[0157] Please refer to Figure 11 In some examples, the control system 2 for monitoring and adjusting laser processing also includes a laser 201, which is configured to communicate directly or indirectly with the host computer 21. The laser is connected (for example, via an optical fiber) to the laser cutting head 24. Under the control of the host computer, the laser generates an initial laser and transmits the initial laser to the laser cutting head 24.

[0158] Please refer to Figure 12 In one embodiment, the laser cutting head 24 includes a collimating lens 242 and a focusing lens 243 disposed inside the housing. The focusing lens 243 is disposed between the nozzle 241 and the collimating lens 242. The nozzle 241 is disposed at one end of the housing close to the object to be processed 25.

[0159] The collimating lens 242 is used to collimate the received initial laser 26a to obtain parallel initial laser light, and transmit the parallel initial laser light to the focusing lens 243;

[0160] The focusing mirror 243 is used to focus the received parallel initial laser light to obtain a focused initial laser light, and transmit the focused initial laser light to the nozzle 241;

[0161] The nozzle 241 is used to transmit the received focused initial laser light out of the laser cutting head 24 to obtain the processing laser light 26 b , and transmit the processing laser light 26 b to the laser action area.

[0162] In some examples, the control system 2 for monitoring and adjusting laser processing also includes a first motor module (not shown), which is electrically connected to the host computer. The first motor module is arranged in the outer shell of the laser cutting head 24. The first motor module is controlled by the host computer 21 to change the position of the collimating mirror 242, thereby adjusting the position of the laser focus.

[0163] In one embodiment, a lower protective mirror 244 is further provided in the housing of the laser cutting head 24 . The lower protective mirror 244 is provided between the focusing mirror 243 and the nozzle 241 to receive the focused initial laser and transmit it to the nozzle 241 .

[0164] In one embodiment, the laser cutting head 24 further includes a dichroic mirror 245.

[0165] The angle between the dichroic mirror 245 and the surface of the object 25 to be processed is a first angle; the dichroic mirror 245 is used to pass the initial laser in the laser cutting head 24;

[0166] The dichroic mirror 245 is further configured to reflect the first image acquisition beam 27a to form a second image acquisition beam 27b, and transmit the second image acquisition beam 27b to the image acquisition device 22; the first image acquisition beam 27a is an image of the laser action area, and the first image acquisition beam 27a overlaps with at least a portion of the initial laser 26a.

[0167] The dichroic mirror 245 can be set at different positions inside the shell of the laser cutting head 24 according to different application environments or actual needs, for example Figure 12 Between the middle focusing mirror 243 and the lower protection mirror 244, for example, Figure 13 Between the collimating lens 242 and the focusing lens 243, for example Figure 14 Above the middle collimating mirror 242.

[0168] In one embodiment of the present invention, the working principle of the dichroic mirror 245 is as follows:

[0169] The dichroic mirror 245 has a high transmittance and a low reflectance for the initial laser 26a with respect to the wavelength, and a high reflectance and a low transmittance for the first image acquisition beam 27a. The dichroic mirror 245 has a high transmittance and a low reflectance for the initial laser 26a, and a high reflectance and a low transmittance for the first image acquisition beam 27a. Therefore, the initial laser 26a can be passed through and the first image acquisition beam 27a can be reflected. Furthermore, the first image acquisition beam 27a (which can be, for example, radiation information of the cutting process) collected by the nozzle 241 can be directly or indirectly reflected to the image acquisition device 22 without affecting the energy of the initial laser 26a.

[0170] In one embodiment of the present invention, the dichroic mirror 245 has a transmittance greater than 99% for a light beam with a wavelength greater than 700 nm, such as the initial laser 26 a ; and a reflectivity greater than 99% for a light beam with a wavelength less than 700 nm, such as the first image acquisition light beam 27 a .

[0171] Please refer to Figure 16 Different from the above embodiments, the dichroic mirror 245 can also be used to reflect the initial laser light 26a through the first image acquisition light beam 27a.

[0172] It can be seen that changes in the control system structure caused by selecting different types of dichroic mirrors due to different actual requirements or application environments of the control system do not deviate from the protection scope of the present invention.

[0173] Please refer to Figure 12 In one embodiment, the control system 2 for monitoring and adjusting laser processing further includes a reflecting device 28, which is disposed between the dichroic mirror 245 and the image acquisition device 22, and is configured to change the optical path of the second image acquisition beam 27b to obtain a second image acquisition beam with a changed optical path, and transmit the second image acquisition beam with a changed optical path to the image acquisition device 22.

[0174] The reflective device 28 may be, for example, a dichroic mirror or a plane reflective mirror, and any such device is within the scope of protection of the present invention as long as it can achieve a change in the light path.

[0175] In one embodiment, the control system 2 for monitoring and adjusting laser processing further includes a beam combiner 29 , and the beam combiner 29 is used to combine the illumination light 231 with the first image acquisition light beam 27 a or the second image acquisition light beam 27 b .

[0176] In the above embodiment, the illumination light source 23 can be arranged beside the second image acquisition light beam 27b, and further, the beam combiner 29 is arranged between the image acquisition device 22 and the dichroic mirror 245, for example Figures 12 to 14 As shown in Figure 12For example, the illumination light 231 passes through the beam combiner 29, the reflective device 28, the dichroic mirror 245, the lower protective mirror 244, and the nozzle 241 in sequence, and finally irradiates the surface of the object to be processed 25 to achieve supplementary illumination light;

[0177] The illumination light source 23 may also be arranged beside the first image collecting light beam 27a, and the beam combining mirror 29 may be arranged between the dichroic mirror 245 and the nozzle 241, for example Figure 15 As shown in FIG, the illumination light 231 passes through the beam combiner 29, the lower protective mirror 244, and the nozzle 241, and finally irradiates the surface of the object to be processed 25, thereby realizing supplementary illumination light.

[0178] In one embodiment, the image acquisition device includes N filters 221 , a lens 222 , and N imaging units 223 , at least one filter 221 can filter out the illumination light 231 , where N ≥ 2;

[0179] A filter 221 is provided between the lens 222 and each imaging unit 223 , and the lens 222 is used to transmit the received second image acquisition light beam 27 b to the filter 221 ;

[0180] The filter 221 is used to filter the light beam of the corresponding frequency band in the received second image acquisition light beam 27b to obtain a target image light beam, and transmit the target image light beam to the corresponding imaging unit 223;

[0181] The imaging unit 223 is communicatively connected to the host computer 21 . The imaging unit 223 is configured to convert a target image beam into a corresponding target image and feed the obtained target image back to the host computer 21 .

[0182] In the above embodiments, the filter 221 can be a single-band (such as a narrow-band filter) or a composite-band (such as a low-pass or high-pass filter); the imaging unit 223 can be a visible light camera (for example, with an operating band of 380-780 nm), a near-infrared camera (NIR for short, with an operating band of 750-1600 nm), or an ultraviolet camera, or a black and white camera or a color camera; the imaging unit 223 can be a laser diode or a laser diode array.

[0183] The operating wavelengths of the components of the illumination light source 23 and the image acquisition device 22 match each other, and thus a corresponding combination of the illumination light source 23 and the image acquisition device 22 can be selected according to the application environment. For example, the illumination light source 23 can be a white light source, the filter can be a low-pass filter, and the imaging unit 223 can be a visible light color camera. For example, the illumination light source 23 can be a light source with an operating wavelength of 808 nm, the filter can be a filter with an operating wavelength of 808 nm, and the imaging unit 223 can be an infrared camera. For example, the illumination light source 23 can be a light source with an operating wavelength of 532 nm, the filter can be a filter with an operating wavelength of 532 nm, and the imaging unit 223 can be a visible light black and white camera. For example, the illumination light source 23 can be a light source with an operating wavelength of 450 nm, the filter can be a low-pass filter, and the imaging unit 223 can be a color camera.

[0184] In some examples, the control system 2 for monitoring and adjusting laser processing also includes a second motor module 202, the second motor module 202 is electrically connected to the host computer, the second motor module 202 is connected to the laser cutting head 24, and the second motor module 202 is controlled by the host computer 21 to achieve a change in the position of the laser cutting head 24, thereby achieving adjustment of the position of the laser focus and the position of the laser cutting head.

[0185] Please refer to Figure 17 , a controller 3 for monitoring and adjusting laser processing, including:

[0186] The image acquisition module 301 acquires at least two target images acquired by the image acquisition device 22, wherein the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment;

[0187] A data processing module 302 is configured to determine processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of the laser cutting head 24 relative to a desired position during laser processing;

[0188] The parameter adjustment module 303 is used to control the operating parameters of the laser according to the processing offset information. The operating parameters include at least one of the following:

[0189] The intensity of the laser output by the nozzle 241 of the laser cutting head and the position parameters of the laser cutting head 24 .

[0190] In one embodiment, the illumination light image includes:

[0191] a pixel portion representing the nozzle profile;

[0192] Characterize the pixel portion of the melt pool;

[0193] The unilluminated image includes:

[0194] Characterizes the pixel portion of the melt pool.

[0195] Please refer to Figure 18 In one embodiment, the data processing module 302 includes:

[0196] An image processing unit 3021 is configured to determine nozzle profile information of the nozzle and molten pool profile information of the molten pool based on the at least two target images;

[0197] an offset determining unit 3022, configured to determine the machining offset information based on the nozzle profile information and the molten pool profile information;

[0198] The nozzle contour information represents the position of the pixel points of the nozzle contour in the image coordinate system, and the molten pool contour information represents the position of the pixel points of the molten pool contour in the image coordinate system.

[0199] In one embodiment, the image processing unit 3021 is specifically configured to:

[0200] Determining the nozzle contour information in the illumination light-containing image according to the grayscale value of each pixel in the illumination light-containing image and the pixel threshold corresponding to the nozzle contour;

[0201] The molten pool contour information is determined in the non-illuminated light image according to the grayscale value of each pixel in the non-illuminated light image and the pixel threshold corresponding to the molten pool contour.

[0202] In one embodiment, the processing offset information includes processing plane offset information; wherein the processing plane offset information represents the offset direction and offset amount of the laser focus on the surface of the object to be processed relative to the nozzle.

[0203] The offset determination unit 3022 is specifically configured to:

[0204] Determining nozzle center information according to the nozzle contour information, wherein the nozzle center information represents a position of a center of the nozzle contour in the image coordinate system;

[0205] Determining laser focus information based on the molten pool contour information, wherein the laser focus information represents the position of the laser focus in the image coordinate system;

[0206] The processing offset information is determined according to the nozzle center information and the laser focus information.

[0207] In one embodiment, the processing offset information includes height offset information; the height offset information represents the offset direction and offset amount of the laser focus in the height direction;

[0208] The offset determination unit 3022 is specifically configured to:

[0209] Determining the width of the molten pool according to the molten pool profile information;

[0210] The processing offset information is determined according to the width information.

[0211] Please refer to Figure 19 In one embodiment, the data processing module 302 further includes:

[0212] The nozzle determination unit 3023 is configured to determine nozzle status information based on the nozzle profile information, where the nozzle status information represents a damage condition of the nozzle.

[0213] In one embodiment, the controller 3 for monitoring and adjusting the laser processing further includes:

[0214] The nozzle replacement module 304 is configured to trigger the replacement of the nozzle according to the nozzle status information.

[0215] Please refer to Figure 20 , provides an electronic device 40, including:

[0216] processor 41; and

[0217] a memory 42 for storing executable instructions of the processor;

[0218] The processor 41 is configured to execute the above-mentioned method by executing the executable instructions.

[0219] The processor 41 can communicate with the memory 42 via a bus 43 .

[0220] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which implements the above-mentioned method when executed by a processor.

[0221] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented by hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0222] Finally, 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for monitoring and adjusting laser processing, characterized in that include: Acquire at least two target images captured by an image acquisition device, wherein the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment; Determining processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of a laser focus relative to a desired position during laser processing; According to the processing offset information, the operating parameters of the laser are controlled, and the operating parameters include at least one of the following: The intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus; The image with illumination light includes: a pixel portion representing the nozzle contour; a pixel portion representing the molten pool; and the image without illumination light includes: a pixel portion representing the molten pool; Determining the processing offset information according to the at least two target images includes: Determining, based on the at least two target images, nozzle contour information of the nozzle and molten pool contour information of the molten pool; the nozzle contour information represents positions of pixel points of the nozzle contour in an image coordinate system, and the molten pool contour information represents positions of pixel points of the molten pool contour in the image coordinate system; The machining offset information is determined according to the nozzle profile information and the molten pool profile information.

2. The control method for monitoring and adjusting laser processing according to claim 1, characterized in that: Determining nozzle profile information of the nozzle and molten pool profile information of the molten pool according to the at least two target images includes: Determining the nozzle contour information in the illumination light-containing image according to the grayscale value of each pixel in the illumination light-containing image and the pixel threshold corresponding to the nozzle contour; The molten pool contour information is determined in the non-illuminated light image according to the grayscale value of each pixel in the non-illuminated light image and the pixel threshold corresponding to the molten pool contour.

3. The control method for monitoring and adjusting laser processing according to claim 2, characterized in that: The processing offset information includes processing plane offset information; Determining the machining offset information according to the nozzle profile information and the molten pool profile information specifically includes: Determining nozzle center information according to the nozzle contour information, wherein the nozzle center information represents a position of a center of the nozzle contour in the image coordinate system; Determining laser focus information based on the molten pool contour information, wherein the laser focus information represents the position of the laser focus in the image coordinate system; The processing offset information is determined according to the nozzle center information and the laser focus information.

4. The control method for monitoring and adjusting laser processing according to claim 2, characterized in that: The processing offset information includes height offset information; Determining the machining offset information according to the nozzle profile information and the molten pool profile information specifically includes: Determining the width of the molten pool according to the molten pool profile information; The processing offset information is determined according to the width information.

5. The control method for monitoring and adjusting laser processing according to claim 1, characterized in that: After determining the nozzle profile information of the nozzle and the molten pool profile information of the molten pool according to the at least two target images, the method further includes: Nozzle status information is determined based on the nozzle profile information, where the nozzle status information represents a damage condition of the nozzle.

6. The control method for monitoring and adjusting laser processing according to claim 5, characterized in that: Also includes: The nozzle replacement is triggered according to the nozzle status information.

7. A control system for monitoring and adjusting laser processing, characterized in that It includes an image acquisition device, a laser cutting head, an illumination light source and a host computer, wherein the laser cutting head is configured to be directly or indirectly controlled by the host computer; The illumination light source is used to continuously supplement the image of the laser action area with illumination light; The laser cutting head is used to output a processing laser through a nozzle to perform laser processing on the object to be processed; The image acquisition device is a multi-channel image acquisition device, which is used to acquire images of the laser action area to form at least two target images and feed them back to the host computer. The at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment; The host computer is used to execute the control method according to any one of claims 1 to 6.

8. The control system for monitoring and adjusting laser processing according to claim 7, characterized in that: The laser cutting head includes a collimating lens and a focusing lens arranged inside a housing, the focusing lens is arranged between the nozzle and the collimating lens, and the nozzle is arranged at one end of the housing close to the object to be processed; The collimating mirror is used to collimate the received initial laser to obtain parallel initial laser, and transmit the parallel initial laser to the focusing mirror; The focusing mirror is used to focus the received parallel initial laser light to obtain a focused initial laser light, and transmit the focused initial laser light to the nozzle; The nozzle is used to transmit the received focused initial laser light out of the laser cutting head to obtain the processing laser light, and transmit the processing laser light to the laser action area.

9. The control system for monitoring and adjusting laser processing according to claim 8, characterized in that: A lower protective mirror is further provided in the housing of the laser cutting head. The lower protective mirror is provided between the focusing mirror and the nozzle to receive the focused initial laser and transmit it to the nozzle.

10. The control system for monitoring and adjusting laser processing according to claim 8, characterized in that: The laser cutting head also includes a dichroic mirror, The angle between the dichroic mirror and the surface of the object to be processed is a first angle; the dichroic mirror is used for allowing the initial laser in the laser cutting head to pass through; The dichroic mirror is also used to reflect the first image capture beam to form a second image capture beam, and transmit the second image capture beam to the image capture device; the first image capture beam is an image of the laser action area captured, and the first image capture beam coincides with at least part of the initial laser.

11. The control system for monitoring and adjusting laser processing according to claim 10, characterized in that: It also includes a reflecting device, which is arranged between the dichroic mirror and the image acquisition device, and is used to change the optical path of the second image acquisition light beam, obtain the second image acquisition light beam with changed optical path, and transmit the second image acquisition light beam with changed optical path to the image acquisition device.

12. The control system for monitoring and adjusting laser processing according to claim 10, characterized in that: It also includes a beam combiner, which is used to combine the illumination light with the first image collection light beam or the second image collection light beam.

13. The control system for monitoring and adjusting laser processing according to claim 10, characterized in that: The image acquisition device includes N filters, a lens, and N imaging units, at least one filter can filter out the illumination light, wherein N ≥ 2; A filter is provided between the lens and each imaging unit, and the lens is used to transmit the received second image acquisition light beam to the filter; The filter is used to filter the light beam of the corresponding frequency band in the received second image acquisition light beam to obtain a target image light beam, and transmit the target image light beam to the corresponding imaging unit; The imaging unit is communicatively connected to the host computer, and is used for converting the target image light beam into a corresponding target image, and feeding the obtained target image back to the host computer.

14. A controller for monitoring and adjusting laser processing, characterized in that For executing the control method according to any one of claims 1 to 6, the controller comprises: An image acquisition module acquires at least two target images acquired by an image acquisition device, wherein the at least two target images include an image with illumination light and an image without illumination light of the laser action area at the same moment; a data processing module, configured to determine processing offset information based on the at least two target images, wherein the processing offset information represents an offset of an actual position of a laser focus relative to a desired position during laser processing; A parameter adjustment module is used to control the operating parameters of the laser according to the processing offset information, and the operating parameters include at least one of the following: The intensity of the laser output by the nozzle of the laser cutting head and the position parameters of the laser focus.

15. An electronic device, characterized in that: Including processor and memory, The memory is used to store codes and related data; The processor is configured to execute the code in the memory to implement the method according to any one of claims 1 to 6.

16. A storage medium storing a computer program, wherein when the program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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