Laser cleaning device and laser cleaning method for workpiece surface

Abstract

The present invention provides a laser cleaning device and a laser cleaning method for a workpiece surface. The device utilizes the advantages of laser being non-contact and environmentally friendly, and avoids the limitations of a contact cleaning method subject to geometric accessibility constraints. An auxiliary line laser emitter is provided to emit a visible line-shaped indication laser to cover the laser focal spot cleaning operation area, thereby enhancing the projection contrast of the curved surface area and making the acquired point cloud data more accurate. The position vector of the moving point of the laser focal spot and the normal vector perpendicular to the moving point and lying on the same tangent plane are obtained based on the Weingarten equation and Gaussian mapping, thereby ultimately achieving that the laser cleaning beam is always perpendicular to the surface of the workpiece to be cleaned. For irregular and complex surfaces such as large power transmission and transformation components, the cleaning operation can be performed while maintaining the optimal working focal length and angle, thereby avoiding the problem of damage and coarsening of the surface of the cleaned area caused by changes in the cleaning angle and working focal length.

Description

Technical Field

[0001] The present invention relates to the field of cleaning technology, and in particular to a laser cleaning device and a laser cleaning method for a workpiece surface. Background Art

[0002] For power infrastructure, such as ultra-high voltage and large-capacity power transmission and transformation components, they are easily contaminated (with bird droppings, ash, etc.). If they are not cleaned for a long time, it may increase power loss and heat generation, and in severe cases, transmission failure may occur, which brings great trouble to power inspection and maintenance.

[0003] Currently, power inspections are mainly carried out manually. In the face of pollution, grinding and chemical spraying are often used for cleaning operations. However, due to geometric accessibility constraints, when grinding and chemical spraying are performed on the irregular and complex surfaces of large power transmission and transformation components, residual pollutants often adhere after the operation, making maintenance difficult to guarantee and easily burying safety hazards. Summary of the Invention

[0004] In order to solve the above-mentioned technical problems, the present invention provides a laser cleaning device for a workpiece surface in a first aspect.

[0005] A second embodiment of the present invention provides a method for laser cleaning the surface of a workpiece.

[0006] The technical solution adopted in the present invention is as follows:

[0007] The first aspect of the present invention provides a laser cleaning device for a workpiece surface, comprising: a cleaning laser generator for generating an invisible cleaning laser beam; a laser cleaning gun head connected to the cleaning laser generator, for focusing the cleaning laser beam onto the workpiece surface to form a laser focal spot in the cleaning operation area; a line laser emitter coupled to the laser cleaning gun head, the line laser emitter being used to emit a visible line-shaped laser coaxial with the cleaning laser beam; a visual measurement camera for collecting point cloud data of the cleaning operation area by collecting the area covered by the visible line-shaped laser, and obtaining spatial point position information of the laser focal spot and a three-dimensional surface model S of the cleaning operation area based on the point cloud data; a control system connected to the visual measurement camera, for obtaining the normal vector of the current laser focal spot on the same tangent plane of the three-dimensional surface model S based on Gaussian mapping and Weingarten equation, and adjusting the laser cleaning gun head according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head is parallel to the normal vector on the same tangent plane.

[0008] The laser cleaning device for workpiece surface of the present invention also has the following additional technical features:

[0009] According to one embodiment of the present invention, the control system is also used to: judge the cleaning effect of the current cleaning operation area based on the hard contaminants attached to the surface of the workpiece; if the set cleaning effect is not achieved, gradually increase the cleaning times of the cleaning operation area until the set cleaning effect is achieved, and then proceed to clean the next cleaning operation area.

[0010] According to one embodiment of the present invention, the control system is further configured to: calibrate the laser focal spot at the center position of the line laser.

[0011] According to one embodiment of the present invention, the control system is specifically used to: use the current laser focal spot as the position vector of a moving point D on the three-dimensional surface model S Expand the first-order derivative to obtain the tangent vector of the moving point D on the three-dimensional surface model S, and based on the Gaussian mapping Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent plane , we get the moving point D in the tangent space Normal vector n(u, v); According to the normal vector n(u, v), the normal vector of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. and .

[0012] According to one embodiment of the present invention, the visual measurement camera is specifically used to: collect point cloud data of the area covered by the visible line laser, identify the point-shaped laser focus as a target, synchronously measure the depth information data of the target, and collect point cloud data of the area surrounding the laser focus as the target, and analyze the point cloud data to obtain spatial point position information of the laser focus and a three-dimensional surface model S of the cleaning operation area.

[0013] The second aspect of the present invention proposes a laser cleaning method for the surface of a workpiece, comprising the following steps: controlling a cleaning laser generator to generate an invisible cleaning laser beam; focusing the cleaning laser beam onto the workpiece surface through a laser cleaning gun head to form a laser focal spot in the cleaning operation area; controlling a line laser emitter to emit a visible line-shaped laser coaxial with the cleaning laser beam; collecting point cloud data of the cleaning operation area by collecting point cloud data of the area covered by the visible line-shaped laser, and obtaining spatial point position information of the laser focal spot and a three-dimensional surface model S of the cleaning operation area based on the point cloud data; obtaining the normal vector of the current laser focal spot on the same tangent plane of the three-dimensional surface model S based on Gaussian mapping and Weingarten equation, and adjusting the laser cleaning gun head according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head is parallel to the normal vector on the same tangent plane.

[0014] The laser cleaning method for a workpiece surface of the present invention also has the following additional technical features:

[0015] According to one embodiment of the present invention, the above method also includes: judging the cleaning effect of the current cleaning operation area based on the hard contaminants attached to the surface of the workpiece; if the set cleaning effect is not achieved, gradually increasing the cleaning times of the cleaning operation area until the set cleaning effect is achieved, and then cleaning the next cleaning operation area.

[0016] According to an embodiment of the present invention, the method further comprises: calibrating the laser focal spot at the center position of the line laser.

[0017] According to one embodiment of the present invention, the normal vector of the current laser focus on the tangent plane of the three-dimensional surface model S is obtained based on the Gaussian mapping and the Weingarten equation, specifically comprising: taking the current laser focus as the position vector of a moving point D on the three-dimensional surface model S Expand the first-order derivative to obtain the tangent vector of the moving point D on the three-dimensional surface model S, and based on the Gaussian mapping Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent plane , we get the moving point D in the tangent space Normal vector n(u, v); According to the normal vector n(u, v), the normal vector of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. and .

[0018] According to one embodiment of the present invention, point cloud data of the cleaning operation area is collected by collecting point cloud data of the area covered by the visible line-shaped laser, and spatial point position information of the laser focus and a three-dimensional surface model S of the cleaning operation area are obtained based on the point cloud data. Specifically, the method includes: collecting point cloud data of the area covered by the visible line-shaped laser, identifying the point-shaped laser focus as a target, synchronously measuring the depth information data of the target, collecting point cloud data of the area surrounding the laser focus as the target, and parsing the point cloud data to obtain spatial point position information of the laser focus and a three-dimensional surface model S of the cleaning operation area.

[0019] Beneficial effects of the present invention:

[0020] The present invention utilizes the advantages of laser cleaning as a non-contact, safe and environmentally friendly processing method, so that the laser beam used in the cleaning operation has the ability to adjust its spatial posture, thereby solving the problem that the cleaning operation is constrained by the geometric accessibility of the irregular and complex surfaces of large power transmission and transformation components.

[0021] The present invention provides an auxiliary line laser transmitter to emit a visible line-shaped indicating laser to cover the laser focal spot cleaning operation area, thereby enhancing the projection contrast of the curved surface area and making the acquired point cloud data more accurate.

[0022] The present invention obtains the position vector of the moving point D of the laser focal spot and the normal vector perpendicular to it and on the same tangent plane based on the Weingarten equation and Gaussian mapping, so that the spatial posture angle of the currently emitted laser beam and the normal vector are parallel on the same tangent plane, and finally realizes that the laser cleaning beam can always be perpendicular to the surface of the workpiece to be cleaned. For irregular and complex surfaces such as large power transmission and transformation components, the cleaning operation can be carried out at the optimal working focal length and angle, avoiding the problem of damage and coarsening of the surface of the cleaned area caused by changes in the cleaning angle and working focal length affecting the energy and uniformity of the cleaning laser beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 1 is a schematic structural diagram of a laser cleaning device for a workpiece surface according to an embodiment of the present invention;

[0024] Figure 2 2 is a schematic structural diagram of a laser cleaning gun head according to an embodiment of the present invention;

[0025] Figure 3 2 is a schematic diagram of the principle of obtaining a normal vector according to an embodiment of the present invention;

[0026] Figure 4 4 is a flow chart of a laser cleaning method for a workpiece surface according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] 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.

[0028] Figure 1 FIG. 1 is a schematic structural diagram of a laser cleaning device for a workpiece surface according to an embodiment of the present invention. Figure 1 As shown, the laser cleaning device includes: a cleaning laser generator 1, a laser cleaning gun head 2, a line laser emitter 3, a visual measurement camera 4 and a control system 5.

[0029] Among them, the cleaning laser generator 1 is used to generate an invisible cleaning laser beam; the laser cleaning gun head 2 is connected to the cleaning laser generator 1, and is used to focus the cleaning laser beam onto the surface of the workpiece to form a laser focal spot in the cleaning operation area; the line laser emitter 3 is coupled to the laser cleaning gun head 2, and the line laser emitter 3 is used to emit a visible line-shaped laser coaxial with the cleaning laser beam; the visual measurement camera 4 is used to collect point cloud data of the cleaning operation area by collecting point cloud data of the area covered by the visible line-shaped laser, and obtain the spatial point position information of the laser focal spot and the three-dimensional surface model S of the cleaning operation area based on the point cloud data; the control system 5 is connected to the visual measurement camera 4, and is used to obtain the normal vector of the current laser focal spot on the tangent plane of the three-dimensional surface model S based on Gaussian mapping and Weingarten equation, and adjust the laser cleaning gun head according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head 2 is parallel to the normal vector on the tangent plane.

[0030] Specifically, if Figure 2 As shown, the laser cleaning gun head 2 is connected to the cleaning laser generator 1 through the optical fiber adapter 201 and the transmission optical fiber 202. The laser cleaning gun head 2 includes: an optical lens group 203, Figure 2 The direction of the middle arrow is the direction of the laser beam emitted by the laser cleaning gun head 2.

[0031] When performing laser cleaning operations on complex curved surface areas, the laser cleaning devices are placed near the workpiece to be cleaned, installed, and powered on for debugging. After calibrating the measurement distance using a measuring tool, the visual measurement camera 4 is placed in the machine position. After calibrating the working focal length using a measuring tool, the laser cleaning gun head 2 is placed, the optical lens group 203 of the laser cleaning device is adjusted, and the line laser emitter 3 is coupled to the laser cleaning gun head 2. After coupling, the indicator light emitted by the line laser emitter 3 is transmitted through the optical lens group 203 inside the laser cleaning gun head and is coaxially emitted with the cleaning laser beam. The line laser emitted by the auxiliary line laser emitter 3 is visible light covering the laser focus cleaning operation area, such as a blue line laser line, which can effectively enhance the projection contrast of the curved surface area, so that the visual measurement camera 4 can collect point cloud data of the area more accurately, and then analyze the point cloud data to obtain the three-dimensional surface model S of the current laser focus cleaning operation area and the spatial point position information of the current laser focus on the surface model S. Based on the Weingarten equation and Gaussian mapping, the current laser focus can be expanded as the position vector of a moving point D on the surface model S in terms of the first-order derivative. According to the obtained moving point D of the laser focus and the normal vector of the tangent plane of the three-dimensional surface model S, and ,Will and Feedback is given to the control system 5, and the control system 5 is based on and Adjust the laser cleaning gun head 2 so that the spatial pose angle of the currently emitted laser beam is consistent with the normal vector and Parallel on the same tangent plane, the laser beam can always be perpendicular to the cleaning target surface. For irregular and complex surfaces such as large power transmission and transformation components, the cleaning operation is maintained at the best working focal length and angle to avoid the changes in cleaning angle and working focal length that affect the energy and uniformity of the cleaning laser beam, causing damage and coarsening of the surface of the cleaned area.

[0032] In one embodiment of the present invention, the control system 5 is also used to: judge the cleaning effect of the current cleaning operation area based on the hard contaminants attached to the surface of the workpiece; if the set cleaning effect is not achieved, gradually increase the cleaning times of the cleaning operation area until the set cleaning effect is achieved, and then proceed to clean the next cleaning operation area.

[0033] Specifically, the control system 5 judges the cleaning effect based on the hard contaminants attached to the surface of the complex curved workpiece. If the set cleaning effect is not achieved, it is determined that the cleaning is not completed. The cleaning times of the curved area are gradually increased until the set cleaning effect is achieved. The next cleaning operation area is cleaned according to the pre-divided cleaning operation area until all cleaning operation areas are completed.

[0034] In one embodiment of the present invention, the control system 5 is further configured to calibrate the laser focal spot at the center of the line laser.

[0035] Specifically, after dividing the cleaning operation area according to the situation of contaminants attached to the workpiece surface, turn on the laser cleaning gun head 2, calibrate the point-shaped laser focus formed by focusing the cleaning laser beam at the center position of the blue line laser emitted by the online laser transmitter, and then the visual measurement camera 4 can accurately collect the point cloud data of the laser focus by collecting the center position of the line laser.

[0036] In a specific embodiment of the present invention, the visual measurement camera 4 is specifically used to: collect point cloud data of the area covered by the visible line laser, identify the point laser focus as the target, synchronously measure the depth information data of the target, and collect point cloud data of the area surrounding the laser focus as the target, analyze the point cloud data to obtain the spatial point position information of the laser focus and the three-dimensional surface model S of the cleaning operation area.

[0037] In a specific embodiment of the present invention, the control system 5 is specifically used to: take the current laser focal spot as the position vector of a moving point D on the three-dimensional surface model S based on the Weingarten equation Expand the first-order derivative to obtain the tangent vector of the moving point D on the three-dimensional surface model S, and based on the Gaussian mapping Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent space , we get the moving point D in the tangent space Normal vector n(u,v); According to the normal vector n(u,v), the normal vector of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. and .

[0038] Specifically, if Figure 3 As shown in Figure 2, based on the Weingarten equation, the current laser focus can be expanded as the position vector of a moving point D on the three-dimensional surface model S in terms of the first-order derivative. That is, when the domain of the current three-dimensional surface model S is set to (u(t), v(t)) in the three-dimensional Euclidean space, its function equation is: , the moving point of the laser focal spot , based on the tangent mapping of Gaussian mapping and Weingarten equation The three-dimensional surface model S at the moving point D can be mapped to the tangent space , the two tangent vectors of the moving point D are expressed as and , then the moving point D is in the tangent space The normal vector n(u,v) is: ,Right now .

[0039] It is understandable that if Figure 1 As shown, the laser cleaning device for the workpiece surface may further include: a power supply box, which is used to provide electrical energy to the laser cleaning device.

[0040] In summary, the laser cleaning device for the workpiece surface according to the embodiment of the present invention utilizes the advantages of non-contact, safe and environmentally friendly laser cleaning processing to enable the laser beam of the cleaning operation to have the ability to adjust its spatial posture, thereby solving the problem that the cleaning operation is constrained by the geometric accessibility of the irregular and complex surfaces of large power transmission and transformation components. The present invention sets an auxiliary line laser emitter to emit a visible line-shaped indicator laser to cover the laser focus cleaning operation area, thereby enhancing the projection contrast of the curved surface area and making the acquired point cloud data more accurate. Based on the Weingarten equation and Gaussian mapping, the present invention obtains the position vector of the moving point D of the laser focus and the normal vector perpendicular to it and on the same tangent plane, so that the spatial posture angle of the currently emitted laser beam and the normal vector are parallel on the same tangent plane, ultimately achieving that the laser cleaning beam can always be perpendicular to the surface of the workpiece to be cleaned. For irregular and complex surfaces such as large power transmission and transformation components, the cleaning operation can be performed at the optimal working focal length and angle, avoiding the problem of affecting the energy and uniformity of the cleaning laser beam due to changes in the cleaning angle and working focal length, causing damage and roughening of the surface of the cleaned area.

[0041] Corresponding to the aforementioned workpiece surface laser cleaning apparatus, the present invention also provides a workpiece surface laser cleaning method. Since the method embodiment of the present invention corresponds to the aforementioned apparatus embodiment, details not disclosed in the apparatus embodiment can be referred to the aforementioned method embodiment and will not be further described in this invention.

[0042] Figure 4 FIG. 1 is a flow chart of a laser cleaning method for a workpiece surface according to an embodiment of the present invention. Figure 4 As shown, the method includes the following steps:

[0043] S1, controls the cleaning laser generator to generate an invisible cleaning laser beam.

[0044] S2, focusing the cleaning laser beam onto the workpiece surface through the laser cleaning gun head to form a laser focal spot in the cleaning operation area.

[0045] S3, controlling the line laser emitter to emit a visible line laser coaxial with the cleaning laser beam.

[0046] S4, collecting point cloud data of the cleaning operation area by collecting point cloud data of the area covered by the visible linear laser, and obtaining spatial point position information of the laser focal spot and a three-dimensional surface model S of the cleaning operation area based on the point cloud data.

[0047] S5, based on Gaussian mapping and Weingarten equation, obtain the normal vector of the current laser focus on the tangent plane of the three-dimensional surface model S, and adjust the laser cleaning gun head according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head is parallel to the normal vector on the tangent plane.

[0048] According to one embodiment of the present invention, the above-mentioned laser cleaning method for the workpiece surface may further include: judging the cleaning effect of the current cleaning operation area based on the hard contaminants attached to the workpiece surface; if the set cleaning effect is not achieved, gradually increasing the cleaning times of the cleaning operation area until the set cleaning effect is achieved, and then cleaning the next cleaning operation area.

[0049] According to one embodiment of the present invention, the above-mentioned laser cleaning method for a workpiece surface may further include: calibrating the laser focal spot to the center position of the linear laser.

[0050] According to one embodiment of the present invention, the above-mentioned laser cleaning method for the workpiece surface may further include: obtaining the normal vector of the tangent plane of the current laser focus on the three-dimensional surface model S based on Gaussian mapping and Weingarten equation, specifically including: taking the current laser focus as the position vector of a moving point D on the three-dimensional surface model S based on the Weingarten equation Expand the first-order derivative to obtain the tangent vector of the moving point D on the three-dimensional surface model S, and based on the Gaussian mapping Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent plane , we get the moving point D in the tangent space Normal vector n(u,v); According to the normal vector n(u,v), the normal vector of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. and .

[0051] According to one embodiment of the present invention, point cloud data of the cleaning operation area is collected by collecting point cloud data of the area covered by the visible line-shaped laser, and spatial point position information of the laser focus and a three-dimensional surface model S of the cleaning operation area are obtained based on the point cloud data. Specifically, the method includes: collecting point cloud data of the area covered by the visible line-shaped laser, identifying the point-shaped laser focus as a target, synchronously measuring the depth information data of the target, collecting point cloud data of the area surrounding the laser focus as the target, and parsing the point cloud data to obtain spatial point position information of the laser focus and a three-dimensional surface model S of the cleaning operation area.

[0052] In summary, the laser cleaning method for the surface of a workpiece according to an embodiment of the present invention utilizes the advantages of non-contact, safe and environmentally friendly laser cleaning processing, so that the laser beam of the cleaning operation has the ability to adjust its spatial posture, thereby solving the problem that the cleaning operation is constrained by the geometric accessibility of the irregular and complex surfaces of large power transmission and transformation components. The present invention sets an auxiliary line laser emitter to emit a visible line-shaped indicator laser to cover the laser focus cleaning operation area, thereby enhancing the projection contrast of the curved surface area and making the acquired point cloud data more accurate. Based on the Weingarten equation and Gaussian mapping, the present invention obtains the position vector of the moving point D of the laser focus and the normal vector perpendicular to it and on the same tangent plane, so that the spatial posture angle of the currently emitted laser beam is parallel to the normal vector on the same tangent plane, and finally realizes that the laser cleaning beam can always be perpendicular to the surface of the workpiece to be cleaned. For irregular and complex surfaces such as large power transmission and transformation components, the cleaning operation can be performed at the optimal working focal length and angle, avoiding the problem of affecting the energy and uniformity of the cleaning laser beam due to changes in the cleaning angle and working focal length, causing damage and coarsening of the surface of the cleaned area.

[0053] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. "Multiple" means two or more, unless otherwise specifically defined.

[0054] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. Throughout this specification, the schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and integrate different embodiments or examples described in this specification, as well as features from different embodiments or examples, without conflicting interpretations. Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. Throughout this specification, the schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and integrate different embodiments or examples and features of different embodiments or examples described in this specification without mutual contradiction.

[0055] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0056] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" is any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (not exhaustive) of computer-readable media include: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0057] It should be understood that various components of the present invention may be implemented using hardware, software, firmware, or a combination thereof. In the aforementioned embodiments, multiple steps or methods may be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any of the following technologies known in the art, or a combination thereof, may be used: a discrete logic circuit having logic gates for implementing logic functions on data signals, an application-specific integrated circuit having suitable combinational logic gates, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

[0058] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0059] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0060] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and are not to be construed as limiting the present invention. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0061] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A laser cleaning device for a workpiece surface, characterized in that: include: A cleaning laser generator, used to generate an invisible cleaning laser beam; a laser cleaning gun head connected to the cleaning laser generator and used to focus the cleaning laser beam onto the workpiece surface to form a laser focal spot in the cleaning operation area; A line laser emitter is coupled to the laser cleaning gun head, and the line laser emitter is used to emit a visible line laser coaxial with the cleaning laser beam; A visual measurement camera is used to collect point cloud data of the cleaning operation area by collecting point cloud data of the area covered by the visible linear laser, and obtain spatial point position information of the laser focal spot and a three-dimensional surface model S of the cleaning operation area based on the point cloud data; A control system, connected to the visual measurement camera, is used to obtain the normal vector of the current laser focus on the tangent plane of the three-dimensional surface model S based on Gaussian mapping and Weingarten equation, and adjust the laser cleaning gun head according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head is parallel to the normal vector on the tangent plane; The control system is specifically used for: Based on the Weingarten equation, the current laser focus is used as the position vector D(u, v) of a moving point D on the three-dimensional surface model S to perform the first-order derivative expansion, and the tangent vector of the moving point D on the three-dimensional surface model S is obtained. * Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent space T g(D) S, get the moving point D in the tangent space T g(D) Normal vector n(u,v) of S; According to the normal vector n(u,v), the normal vector n of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. u and n v .

2. The laser cleaning device for a workpiece surface according to claim 1, characterized in that: The control system is also used to: The cleaning effect of the current cleaning operation area is judged according to the hard contaminants attached to the surface of the workpiece. If the set cleaning effect is not achieved, the cleaning times of the cleaning operation area are gradually increased until the set cleaning effect is achieved, and then the cleaning of the next cleaning operation area is carried out.

3. The laser cleaning device for a workpiece surface according to claim 1, characterized in that: The control system is further used to calibrate the laser focal spot at the center position of the line laser.

4. The laser cleaning device for a workpiece surface according to claim 1, characterized in that: The visual measurement camera is specifically used for: Collect point cloud data of the area covered by the visible line laser, identify the point laser focus as the target, synchronously measure the depth information data of the target, and collect point cloud data of the area surrounding the laser focus as the target. Analyze the point cloud data to obtain the spatial point position information of the laser focus and the three-dimensional surface model S of the cleaning operation area.

5. A laser cleaning method for a workpiece surface, characterized in that: The following steps are involved: Controlling the cleaning laser generator to generate an invisible cleaning laser beam; Focusing the cleaning laser beam onto the workpiece surface through a laser cleaning gun head to form a laser focal spot in the cleaning operation area; The control line laser transmitter emits a visible line laser coaxial with the cleaning laser beam; Collecting point cloud data of the cleaning operation area by collecting point cloud data of the area covered by the visible linear laser, and obtaining spatial point position information of the laser focal spot and a three-dimensional surface model S of the cleaning operation area according to the point cloud data; Based on Gaussian mapping and Weingarten equation, the normal vector of the current laser focus on the tangent plane of the three-dimensional surface model S is obtained, and the laser cleaning gun head is adjusted according to the normal vector so that the spatial posture angle of the laser beam currently emitted by the laser cleaning gun head is parallel to the normal vector on the tangent plane; The normal vector of the tangent plane of the three-dimensional surface model S is obtained based on the Gaussian mapping and the Weingarten equation, specifically including: Based on the Weingarten equation, the current laser focus is used as the position vector D(u, v) of a moving point D on the three-dimensional surface model S to perform the first-order derivative expansion, and the tangent vector of the moving point D on the three-dimensional surface model S is obtained. * Map the tangent vector of the moving point D on the three-dimensional surface model S to the tangent plane T g(D) S, get the moving point D in the tangent space T g(D) Normal vector n(u,v) of S; According to the normal vector n(u,v), the normal vector n of the moving point D on the tangent plane of the three-dimensional surface model S is obtained. u and n v .

6. The laser cleaning method for a workpiece surface according to claim 5, characterized in that: Also includes: The cleaning effect of the current cleaning operation area is judged according to the hard contaminants attached to the surface of the workpiece. If the set cleaning effect is not achieved, the cleaning times of the cleaning operation area are gradually increased until the set cleaning effect is achieved, and then the cleaning of the next cleaning operation area is carried out.

7. The laser cleaning method for a workpiece surface according to claim 5, characterized in that: Also includes: Calibrate the laser focal spot at the center of the line laser.

8. The laser cleaning method for a workpiece surface according to claim 5, characterized in that: The point cloud data of the cleaning operation area is collected by collecting the point cloud data of the area covered by the visible linear laser, and the spatial point position information of the laser focal spot and the three-dimensional surface model S of the cleaning operation area are obtained according to the point cloud data, specifically including: Collect point cloud data of the area covered by the visible line laser, identify the point laser focus as the target, synchronously measure the depth information data of the target, and collect point cloud data of the area surrounding the laser focus as the target. Analyze the point cloud data to obtain the spatial point position information of the laser focus and the three-dimensional surface model S of the cleaning operation area.

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