Closed-loop control system and method for large-format dynamic scanning in laser peen forming

Abstract

A closed-loop control system and method for large-format dynamic scanning in laser peen forming. The system comprises: a laser module, configured to generate laser and feed back a laser emission signal; an optical module, configured to realize spot correction and focusing and large-range dynamic scanning; and a control module, configured to realize closed-loop control of laser emission and emission feedback. By means of closed-loop control of dynamic scanning, spot correction and focusing of laser beams under large-range machining are achieved, the problems of no laser emission and disordered laser emission during laser peen machining are solved, the consistency of spots at all positions in a certain area and the machining position precision of laser peen machining are guaranteed, and the machining quality is improved.

Description

A large-scale dynamic scanning closed-loop control system and method for laser shot peening Technical Field

[0001] The present invention relates to the field of laser processing technology, and in particular to a large-scale dynamic scanning closed-loop control system and method for laser shot peening. Background Art

[0002] Laser shot peening utilizes the plasma impact mechanics of laser-induced blasts to generate high-amplitude residual stress fields on the surface and depth of a part, causing it to bend and deform. This process can effectively improve a part's fatigue and corrosion resistance. Due to its unique technical advantages, it holds broad application prospects in the forming of large, integral panels in aerospace, rail transit, and other applications.

[0003] Laser shot peening for large integral wall panels generally involves two methods and devices: a fixed optical path and dynamic scanning. For the fixed optical path method, the existing patent, "Method and Apparatus for Laser Shot Peening of Medium-Thick Plates" (Patent No. ZL200510040116.9), proposes a laser shot peening system that maintains a fixed optical path and utilizes a five-axis CNC machine tool to control the movement of the workpiece. Alternatively, the optical path can be maintained stationary, with robotic gripping controlling the movement of the workpiece for laser shot peening. The disadvantage of this fixed optical path method is that the workpiece requires movement, which places high demands on equipment movement and processing space, making it difficult to meet the forming needs of larger workpieces.

[0004] For dynamic scanning forming systems, the existing patent "An optical path device and method for laser shot peening of large workpieces" (patent number CN201510197097.4) provides a large-format dynamic scanning device suitable for large workpieces. The spot shape adjustment at different positions is achieved by moving back and forth and rotating synchronously with two orthogonal cylindrical mirrors. Dynamic scanning of the laser large format is achieved through a two-axis galvanometer. The optical path device is simple to arrange, easy to move and has a small range. It ensures dynamic correction and focusing of the spot shape at any position in space, which is an effective way to achieve laser shot peening of large wall panels. However, the current implementation method of the dynamic scanning forming system is mainly that the optical system (including galvanometer, optical path correction and focusing module, etc.) and the laser are controlled and operated separately, and the movement speed of the optical system needs to match the laser light frequency. However, when the movement speed of the optical system cannot match the laser light frequency or when the galvanometer jumps over a large range, there will be problems such as inaccurate light position, missed processing points or excess light, making it difficult to achieve precise control of the laser pulse, affecting the wall panel forming quality.

[0005] Summary of the Invention

[0006] In view of the defects in the prior art, the purpose of the present invention is to provide a large-scale dynamic scanning closed-loop control system and method for laser shot peening.

[0007] According to a first aspect of the present invention, there is provided a large-scale dynamic scanning closed-loop control system for laser shot peening, comprising:

[0008] A laser module, which is used to generate laser light and feed back laser output signals;

[0009] An optical module, which is used to achieve correction and focusing of the light spot and large-scale dynamic scanning;

[0010] A control module is used to realize closed-loop control of laser light emission and light emission feedback.

[0011] Preferably, the laser module comprises:

[0012] a laser, wherein the laser is used to emit laser light;

[0013] An energy meter is connected to the laser and is used to detect laser light emission. When the laser light emission is detected, an electrical signal is fed back to the control module.

[0014] Preferably, the optical module includes:

[0015] An optical path correction and focusing unit, which is used to achieve shape correction and dynamic focusing of the light spot at any position;

[0016] A two-axis galvanometer, which realizes the deflection of the laser X-axis and Y-axis by controlling the rotation angle of the two axes, thereby realizing large-scale dynamic scanning of the laser;

[0017] An optical motion control board is used to control the optical path correction and focusing unit to achieve laser spot correction and focusing at different positions, to control the two-axis galvanometer to achieve large-scale dynamic scanning, and to provide feedback on the spatial motion status of the optical path correction and focusing unit and the two-axis galvanometer.

[0018] Preferably, the optical path correction and focusing unit comprises:

[0019] Front and rear cylindrical mirrors, wherein the front and rear cylindrical mirrors are two concave cylindrical lenses arranged in front of each other, the cylindrical generatrixes of the two concave cylindrical lenses remain orthogonal, and both can independently translate along the optical axis and can synchronously rotate around the optical axis;

[0020] A focusing convex lens, wherein the focusing convex lens is used to focus the incident laser light;

[0021] An optical motion platform is equipped with the front and rear cylindrical mirrors, and is used to control the two cylindrical mirrors to move forward and backward and rotate synchronously, thereby achieving spot correction and dynamic focusing.

[0022] Preferably, the control module includes:

[0023] A host computer, which is used to define the point position of the laser impact and generate the control parameters of the optical module movement;

[0024] The controller is used to receive electrical signals from the laser module and the optical motion control board, and when receiving the motion arrival signal from the optical motion control board, controls the laser module to emit light; when receiving the light emission signal fed back by the laser module, controls the laser module to stop emitting light.

[0025] According to a second aspect of the present invention, a large-scale dynamic scanning control method for laser shot peening is provided, comprising:

[0026] The host computer generates a point file containing the optical path correction and focusing unit, and the two-axis galvanometer motion parameters;

[0027] After receiving the position file from the host computer, the control module controls the movement of the optical path correction and focusing unit and the two-axis galvanometer;

[0028] After the optical path correction and focusing unit and the two-axis galvanometer move to the target point in the point file, a movement-to-position signal is triggered;

[0029] According to the movement-to-position signal, a closed-loop control of laser light emission and light emission feedback is formed;

[0030] The optical module moves to the next target point according to the closed-loop control.

[0031] Preferably, after the optical path correction and focusing unit and the two-axis galvanometer move to the target point in the point file, triggering a movement-to-position signal includes:

[0032] The optical path motion control board controls the front and rear cylindrical mirrors to move forward and backward to corresponding positions and rotate synchronously to achieve spot correction and focusing;

[0033] The optical path motion control board controls the galvanometer to deflect the laser spot;

[0034] When the laser spot moves to the target position, the optical motion control board feeds back the movement arrival signal to the controller.

[0035] Preferably, according to the motion-to-position signal, a closed-loop control of laser light emission and light emission feedback is formed, including:

[0036] The optical module moves into position and sends a movement-in-position signal to the control module;

[0037] After receiving the motion arrival signal, the control module sends a light output signal to the laser, and the laser controls the laser to emit light after receiving the light output signal;

[0038] When the energy meter detects the laser light output signal, it sends a light output completion signal to the controller;

[0039] After receiving the light emission completion signal, the control module sends a light emission stop signal to the laser, and the laser stops emitting light after receiving the light emission stop signal.

[0040] According to the third aspect of the present invention, there is provided a terminal comprising a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the program, the terminal can be used to operate the large-format dynamic scanning closed-loop control system for laser shot peening, or to execute the large-format dynamic scanning closed-loop control method for laser shot peening.

[0041] According to the fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, it can be used to run the laser shot peening large-format dynamic scanning closed-loop control system, or to execute the laser shot peening large-format dynamic scanning closed-loop control method.

[0042] Compared with the prior art, the embodiments of the present invention have at least one of the following beneficial effects:

[0043] The closed-loop control method and system of laser light emission and light emission feedback in the embodiment of the present invention realizes closed-loop control of light path movement into position - laser light emission - light emission feedback, avoids the problems of no light emission or random light emission during laser shot peening, and improves the quality of shot peening.

[0044] The closed-loop control method and system for laser light emission and light emission feedback in the embodiments of the present invention realizes the spot correction and focusing of the laser beam under large-scale processing, ensuring the consistency of the spot at each position in a certain area during laser shot peening processing.

[0045] The closed-loop control method and system for laser emission and light emission feedback in the embodiment of the present invention triggers the laser after the optical path moves into place, and the laser continues to move after emitting light, thereby ensuring the position accuracy of the laser emission. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0047] FIG1 is a schematic structural diagram of a laser shot peening control system according to an embodiment of the present invention;

[0048] FIG2 is a control flow chart of a laser shot peening control system method according to an embodiment of the present invention.

[0049] In the figure, 1-laser, 2-energy meter, 3-laser beam, 4-optical platform, 5-front cylindrical mirror, 6-rear cylindrical mirror, 7-focusing convex lens, 8-end workpiece, 9-two-axis galvanometer, 10-optical motion control board, 11-controller, 12-host computer. DETAILED DESCRIPTION

[0050] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0051] The present invention provides an embodiment, see Figure 1, a large-scale dynamic scanning closed-loop control system for laser shot peening, including a laser module, an optical module and a control module; the laser module is used to generate laser and feedback laser light output signal; the optical module is used to realize the correction and focusing of the light spot and large-scale dynamic scanning; the control module is used to realize closed-loop control of laser light output and light output feedback.

[0052] This embodiment realizes closed-loop control of light path movement into position - laser light emission - light emission feedback, thereby avoiding the problems of no light emission or random light emission in non-processing positions during laser shot peening processing, and improving the quality of shot peening processing.

[0053] In a preferred embodiment of the present invention, a preferred structure of a laser module is provided, including a laser 1 and an energy meter 2 .

[0054] The laser 1 is used to emit laser light; the energy meter 2 is connected to the laser 1 and is used to detect the laser light. When the laser light is detected, an electrical signal is fed back to the control module.

[0055] In a preferred embodiment of the present invention, a preferred structure of an optical module is provided, comprising an optical path correction and focusing unit, a two-axis galvanometer 9, and an optical motion control board 10. The correction and focusing unit is used to achieve shape correction and dynamic focusing of the light spot at any position; the two-axis galvanometer 9 achieves deflection of the laser along the X and Y axes by controlling the rotation angles of the two axes, thereby achieving large-scale dynamic scanning of the laser. The optical motion control board 10 is used to control the optical path correction and focusing unit to achieve correction and focusing of the laser spot at different positions, to control the two-axis galvanometer to achieve large-scale dynamic scanning, and to provide feedback on the spatial motion status of the optical path correction and focusing unit and the two-axis galvanometer.

[0056] In a preferred embodiment, a further structure of the optical path correction and focusing unit is provided, including front and rear cylindrical mirrors (i.e., front cylindrical mirror 5 and rear cylindrical mirror 6), a focusing convex lens 7, and an optical motion platform 4. The front and rear cylindrical mirrors 5 and 6 are two concave cylindrical lenses arranged in front of each other, and the cylindrical generatrixes of the two concave cylindrical lenses remain orthogonal. Both can independently translate along the optical axis and can rotate synchronously around the optical axis. The focusing convex lens 7 is used to focus the incident laser; the optical motion platform 4 is equipped with the front and rear cylindrical mirrors 5 and 6, and is used to control the forward and backward movement and synchronous rotation of the two cylindrical mirrors, thereby achieving spot correction and dynamic focusing.

[0057] In a preferred embodiment of the present invention, a preferred structure of a control module is provided, comprising a host computer 12 and a controller 11. The host computer 12 is used to define the point position of the laser impact and generate the control parameters of the optical module movement; the controller 11 is used to receive electrical signals from the laser module and the optical motion control board. Upon receiving the motion position signal from the optical motion control board 10, the controller controls the laser 1 to emit light; upon receiving the light emission signal fed back by the energy meter 2, the controller controls the laser 1 to stop emitting light.

[0058] In a preferred embodiment of the present invention, a preferred process for closed-loop control of laser light emission and light emission feedback is provided, including:

[0059] After the optical module moves to the right position, the optical path motion control board 10 sends a movement-to-right position signal to the controller 11;

[0060] After receiving the motion arrival signal, the controller 11 sends a light output signal to the laser 1. After receiving the light output signal, the laser 1 controls the laser to emit light.

[0061] When the energy meter 2 detects the laser light emission signal, it sends a light emission completion signal to the controller 11. After receiving the light emission completion signal, the controller 11 sends a stop light emission signal to the laser 1. After receiving the stop light emission signal, the laser 1 stops emitting light.

[0062] Based on the same inventive concept, in another embodiment, a large-scale dynamic scanning control method for laser shot peening is provided, as shown in FIG2 , and the steps include:

[0063] S1, the host computer 12 generates a point file containing the motion parameters of the optical path correction and focusing unit and the two-axis galvanometer 9;

[0064] S2, after the control module receives the upper computer point file in S1, it controls the movement of the optical path correction and focusing module and the two-axis galvanometer 9;

[0065] S3, after the optical path correction and focusing unit and the two-axis galvanometer move to the target point in the point file, a movement-to-position signal is triggered;

[0066] S4, the motion control board 10 sends a motion-in-place signal to the controller 11;

[0067] S5, after receiving the motion in place signal, the controller 11 sends a light output signal to the laser 1, and after receiving the light output signal, the laser controls the laser 3 to emit light;

[0068] S6, when the energy meter 2 detects the laser light emission signal, it sends a light emission completion signal to the controller 11. After receiving the light emission completion signal, the controller 11 sends a stop light emission signal to the laser 1. After receiving the stop light emission signal, the laser 1 stops emitting light. One laser shot peening position is processed.

[0069] S7, repeat S2-S6 until all laser shot peening positions are processed.

[0070] In a preferred embodiment of the present invention, a specific implementation process of step S3 in the above embodiment is provided, including:

[0071] S31, the optical path motion control board 10 controls the front and rear cylindrical mirrors 5 and 6 to move forward and backward to corresponding positions and rotate synchronously to achieve spot correction and focusing;

[0072] S32, the optical path motion control board 10 controls the galvanometer to deflect the laser spot;

[0073] S33 , when the laser spot moves to the target position, the optical path motion control board 10 feeds back a movement arrival signal to the controller 1 .

[0074] The above-mentioned embodiments propose a method for precise single-laser pulse output and a closed-loop control system based on "light output control and light output feedback." This establishes a synchronous closed-loop control system for pulsed laser output, achieving precise matching of the laser triggering time with the movement time, effectively resolving issues such as laser light output failure or erratic light output. Furthermore, it maximizes the laser's light output frequency, significantly improving laser processing efficiency.

[0075] Based on the same inventive concept, in other embodiments of the present invention, a terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the terminal can be used to execute the above-mentioned method, or to run the above-mentioned system.

[0076] Optionally, the memory is used to store programs; the memory may include volatile memory (English: volatile memory), such as random-access memory (English: random-access memory, abbreviated: RAM), such as static random-access memory (English: static random-access memory, abbreviated: SRAM), double data rate synchronous dynamic random access memory (English: Double Data Rate Synchronous Dynamic Random Access Memory, abbreviated: DDR SDRAM), etc.; the memory may also include non-volatile memory (English: non-volatile memory), such as flash memory (English: flash memory). The memory is used to store computer programs (such as applications, functional modules, etc. that implement the above-mentioned methods), computer instructions, etc., and the above-mentioned computer programs, computer instructions, etc. can be partitioned and stored in one or more memories.

[0077] The aforementioned computer programs, computer instructions, etc. may be partitioned and stored in one or more memories, and the aforementioned computer programs, computer instructions, data, etc. may be called by a processor.

[0078] The processor is configured to execute the computer program stored in the memory to implement the various steps of the method involved in the above embodiment. For details, please refer to the relevant description in the above method embodiment.

[0079] The processor and memory can be independent structures or integrated structures. When the processor and memory are independent structures, the memory and processor can be coupled via a bus.

[0080] Based on the same inventive concept, in other embodiments of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, it can be used to execute the above method or run the above system.

[0081] Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of computer programs from one location to another. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer. An exemplary storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and storage medium can be located in an ASIC. Alternatively, the ASIC can be located in a user device. Of course, the processor and storage medium can also exist as discrete components in a communication device.

[0082] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0083] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0084] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0085] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0086] The above-mentioned embodiments propose a method for precise single-laser pulse output and a closed-loop control system based on "light output control and light output feedback." This establishes a synchronous closed-loop control system for pulsed laser output, achieving precise matching of the laser triggering time with the movement time, effectively resolving issues such as laser light output failure or erratic light output. Furthermore, it maximizes the laser's light output frequency, significantly improving laser processing efficiency.

[0087] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various modifications or variations within the scope of the claims without affecting the essence of the present invention. The above preferred features may be used in any combination as long as they do not conflict with each other.

Claims

1. A large-format dynamic scanning closed-loop control system for laser shot peening, characterized in that: include: A laser module, wherein the laser module is used to generate laser light and feed back laser light output signals; An optical module, which is used to achieve correction and focusing of the light spot and large-range dynamic scanning; A control module, which is used to realize closed-loop control of laser light emission and light emission feedback. ; The laser module comprises: A laser, wherein the laser is used to emit laser light; An energy meter, the energy meter is connected to the laser and is used to detect laser light emission, and feeds back an electrical signal to the control module when the laser light emission is detected; The optical module comprises: An optical path correction and focusing unit, which is used to achieve shape correction and dynamic focusing of the light spot at any position; A two-axis galvanometer, which realizes the deflection of the laser X-axis and Y-axis by controlling the rotation angle of the two axes, thereby realizing large-scale dynamic scanning of the laser; An optical motion control board, which is used to control the optical path correction and focusing unit to achieve laser spot correction and focusing at different positions, to control the two-axis galvanometer to achieve a wide range of dynamic scanning, and to feedback the spatial motion state of the optical path correction and focusing unit and the two-axis galvanometer; The control module comprises: A host computer, which is used to define the point positions of the laser impact and generate control parameters for the movement of the optical module; The controller is used to receive the electrical signals of the laser module and the optical motion control board, and when receiving the motion arrival signal of the optical motion control board, controls the laser module to emit light; when receiving the light emission signal fed back by the laser module, controls the laser module to stop emitting light.

2. According to claim 1, a large-format dynamic scanning closed-loop control system for laser shot peening is characterized in that: The optical path correction and focusing unit comprises: Front and rear cylindrical mirrors, the front and rear cylindrical mirrors are two concave cylindrical lenses arranged front and back, the cylindrical generatrixes of the two concave cylindrical lenses remain orthogonal, and both can independently translate along the optical axis direction and can synchronously rotate around the optical axis; A focusing convex lens, wherein the focusing convex lens is used to focus the incident laser; An optical motion platform, the optical motion platform is equipped with the front and rear cylindrical mirrors, and is used to control the two cylindrical mirrors to move respectively Move forward and backward and rotate synchronously to achieve spot correction and dynamic focusing.

3. A large-format dynamic scanning control method for laser shot peening, characterized in that: include: The host computer generates a point file containing the optical path correction and focusing unit, and the two-axis galvanometer motion parameters; After receiving the position file of the host computer, the control module controls the movement of the optical path correction and focusing unit and the two-axis galvanometer; After the optical path correction and focusing unit and the two-axis galvanometer move to the target point in the point file, a movement-to-position signal is triggered; According to the movement-in-place signal, a closed-loop control of laser light emission and light emission feedback is formed; The optical module moves to the next target point according to the closed-loop control.

4. A large-format dynamic scanning control method for laser shot peening according to claim 3, characterized in that: After the optical path correction and focusing unit and the two-axis galvanometer move to the target point in the point file, a movement-to-position signal is triggered, including: The optical path motion control board controls the front and rear cylindrical mirrors to move forward and backward to the corresponding positions and rotate synchronously to achieve spot correction and focusing; The optical path motion control board controls the galvanometer to deflect the laser spot; When the laser spot moves to the target position, the optical path motion control board feeds back the movement arrival signal to the controller.

5. A large-format dynamic scanning closed-loop control method for laser shot peening according to claim 4, characterized in that: According to the motion-to-position signal, a closed-loop control of laser light emission and light emission feedback is formed, including: The optical module moves to the desired position and sends a signal of movement to the control module; After receiving the motion-to-position signal, the control module sends a light-emitting signal to the laser, and after receiving the light-emitting signal, the laser controls the laser to emit light; When the energy meter detects the laser light output signal, it sends a light output completion signal to the controller; After receiving the light emission completion signal, the control module sends a light emission stop signal to the laser, and the laser stops emitting light after receiving the light emission stop signal.

6. A terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, it can be used to run the system described in claims 1-2, or execute the method described in any one of claims 3-5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, it can be used to run the system described in any one of claims 1-2, or to execute the method described in any one of claims 3-5.

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