A self-adapting positioning device for a laser cleaning system suitable for uneven ground movement

Abstract

The application discloses a kind of laser cleaning system adaptive positioning device suitable for uneven ground movement, to solve the problem of the existing laser cleaning system in uneven ground operation due to the dynamic change of vehicle pose causes cleaning head positioning precision to decline.This application includes unmanned vehicle platform, high-precision lifting rotating platform and relative position sensing device.Relative position sensing device real-time acquisition laser cleaning head and the relative pose change between the surface of the workpiece to be cleaned, and the change is transmitted to the control system;Control system drives high-precision lifting rotating module or industrial robot controller to carry out multi-degree-of-freedom dynamic compensation, so that the relative position between cleaning head and workpiece surface remains constant.This application does not need to lay steel rail or slide, can effectively overcome the up-and-down jitter, pitch, roll and yaw disturbance caused by ground undulation, significantly improve the operation precision and stability of laser cleaning system under complex terrain, suitable for automatic laser cleaning of large structural parts.

Description

Technical Field

[0001] This invention belongs to the field of laser cleaning and automation equipment technology, and particularly relates to an adaptive positioning device for a laser cleaning system that is suitable for moving on uneven ground. Background Technology

[0002] Laser cleaning technology is increasingly widely used in metal processing, automotive manufacturing, aerospace repair, and pre-coating treatment due to its advantages such as non-contact operation, no consumables, environmental friendliness, and ease of automation integration. Compared with traditional mechanical grinding, chemical cleaning, or sandblasting, laser cleaning can selectively remove contaminants, reduce damage to the substrate, and lower waste emissions and operational safety risks, making it an important development direction in the surface treatment field.

[0003] In cleaning operations involving large structural components or complex curved surfaces, integrating laser cleaning heads into automated mobile platforms is a common technological approach to achieve efficient, large-scale operations. In existing technologies, some automated laser cleaning systems mount the cleaning head on a mobile carrier, which transports the laser cleaning equipment to the designated work area. An industrial robot then drives the cleaning head to scan and clean the workpiece. To ensure a precise relative position between the laser cleaning head and the workpiece surface, such systems place extremely high demands on the flatness of the operating surface of the mobile carrier. Therefore, existing solutions often employ the method of laying steel rails or tracks in the work area to eliminate the impact of ground undulations on the carrier's attitude stability, thereby providing a relatively flat operating foundation for the cleaning head.

[0004] However, in practical industrial applications, many laser cleaning operations are often located outdoors or on unpaved workshop floors, making it difficult to lay rails or tracks. Even if rails could be laid, the cost is high, and besides limiting their application range, the rails themselves can cause localized bumps or depressions in the ground, affecting the cross-operation of other processes and the flow of materials on site. Without rails or tracks, when mobile vehicles need to travel or stop on uneven ground, the undulating terrain will cause the vehicle to shake vertically, sway horizontally, and undergo multi-degree-of-freedom pose changes such as pitch, roll, and yaw, which are directly transmitted to the industrial robot and cleaning head mounted on it, resulting in a shift in the relative position between the cleaning head and the workpiece surface. Existing automated laser cleaning systems generally lack real-time compensation mechanisms for pose errors caused by uneven ground. Relying solely on initial position calibration or offline robot programming is insufficient to cope with random disturbances during operation, thus affecting the tracking accuracy of the cleaning trajectory and the consistency of the cleaning effect, and in severe cases, may lead to poor cleaning or workpiece damage.

[0005] Therefore, how to effectively overcome the dynamic error of the cleaning head position caused by uneven working ground without laying steel rails or slides, and ensure the positioning accuracy and operational stability of the laser cleaning system under complex terrain conditions, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides an adaptive positioning device for a laser cleaning system suitable for movement on uneven ground, the specific technical solution of which is as follows: An adaptive positioning device for a laser cleaning system suitable for movement on uneven ground is disclosed. The laser cleaning system includes an unmanned mobile platform, an industrial robot mounted on the unmanned mobile platform, and a laser cleaning head driven by the industrial robot. The adaptive positioning device is positioned between the laser cleaning system and the workpiece to be cleaned, and is used to detect and dynamically compensate for the relative pose error between the laser cleaning head and the surface of the workpiece to be cleaned caused by the unevenness of the working ground in real time.

[0007] Furthermore, the adaptive positioning device includes: a relative position sensing device for detecting and feeding back changes in the pose of the industrial robot base relative to the surface of the workpiece to be cleaned, and a lifting and rotating platform for adaptively adjusting the pose of the industrial robot base according to the changes in pose. The lifting and rotating platform includes: X-axis motion guide (411A), X-axis guide slider (411B), X-axis motion platform (411C). Y-axis motion guide (412A), Y-axis guide slider (412B), Y-axis motion platform (412C); Z-axis motion guide (413A), Z-axis guide slider (413B), Z-axis motion platform (413C). γ shaft (414A) and γ shaft bearing (414B), ball shaft (415A) and ball shaft bearing (415B). The ball bearing (415B) is fixedly mounted on the unmanned mobile platform. The ball shaft (415A) rotates within the ball bearing (415B) to achieve adaptive adjustment of the pitch angle α and roll angle β under external force. The γ-axis bearing (414B) is fixedly mounted above the ball shaft (415A). The γ-axis (414A) rotates freely within the γ-axis bearing (414B) to achieve adaptive adjustment of the yaw angle γ under external force. The Y-axis motion platform (412C) is integrated with the γ-axis (414A) and fixedly mounted above the γ-axis (414A). The Y-axis motion guide rail (412A) is fixedly mounted on the Y-axis motion platform (412C). A Y-axis guide rail slider (412B) is provided on the Y-axis motion guide rail (412A), and the Y-axis guide rail slider (412B) moves along the Y-axis motion guide rail (412A). The X-axis motion guide rail (411A) is fixedly mounted on the Y-axis guide rail slider (412B), and the X-axis motion guide rail (411A) is provided with an X-axis guide rail slider (411B). The X-axis guide rail slider (411B) slides freely along the X-axis motion guide rail (411A) in the X direction. The X-axis guide rail slider (411B) is also fixedly mounted with an X-axis motion platform (411C). The Z-axis motion guide rail (413A) is vertically fixedly mounted on the X-axis motion platform (411C), and the Z-axis motion guide rail (413A) is provided with a Z-axis guide rail slider (413B). The Z-axis guide rail slider (413B) slides freely along the Z-axis motion guide rail (413A) in the vertical direction. The Z-axis guide rail slider (413B) is also fixedly mounted with a Z-axis motion platform (413C), which is used to support and fix the industrial robot.

[0008] Preferably, the Z-axis motion guide rails (413A) are configured as two or more parallel and opposite, and each Z-axis motion guide rail (413A) is provided with a Z-axis guide rail slider (413B). The two or more Z-axis guide rail sliders (413B) are used to fix and connect the Z-axis motion platform (413C).

[0009] Preferably, the X-axis motion guide rail (411A) can be set as two or more parallel and opposite, and an X-axis guide rail slider (411B) is respectively set on each X-axis motion guide rail (411A). The two or more X-axis guide rail sliders (411B) are used to fix the X-axis motion platform (411C).

[0010] Preferably, the Y-axis motion guide rail (412A) can be set as two or more parallel and opposite, and a Y-axis guide rail slider (412B) is respectively set on each Y-axis motion guide rail (412A). The two or more Y-axis guide rail sliders (412B) are used to fix the Y-axis motion platform (412C).

[0011] Furthermore, the relative position sensing device is a mechanical contact type, including a rod (421). One end of the rod (421) is fixedly connected to the Z-axis motion platform (413C) or the industrial robot base; the other end of the rod (421) is fixedly connected to a frame (422), which has an upper branch (4221) and a lower branch (4222), and each branch end is provided with a wheel set (423); the vertical distance between the upper and lower branches is adjusted according to the thickness of the positioning features on the workpiece to be cleaned, so that... The wheel assembly (423) fits tightly against the upper and lower surfaces of the positioning feature; the wheel assembly (423) has a drive motor to make the relative position sensing device move stably in the X-axis direction, thereby driving the X-axis motion platform (411C) to move at a stable speed; a strong magnet (424) is also provided on the frame or fork to attract the frame to the side of the positioning feature, ensuring that the relative position in the Y direction is fixed; the positioning feature refers to the structure located on the workpiece to be cleaned for auxiliary positioning, including the geometric structure inherent to the workpiece itself or artificially added.

[0012] In another embodiment, each axis of the lifting and rotating platform is equipped with a driver to drive the lifting and rotating platform to adjust its posture according to the posture change; the relative position sensing device is photoelectric non-contact type, including a rod (421), one end of which is fixedly connected to the Z-axis motion platform (413C) or the industrial robot base; the other end of the rod (421) is fixedly connected to a plate (425), and a first photoelectric sensor (4251) and a second photoelectric sensor (4252) are provided on the plate (425). A positioning plate (72) is vertically fixed on the workpiece to be cleaned. The positioning plate (72) is equipped with a first rangefinder (721), a second rangefinder (722), a third rangefinder (723), a first laser emitter (724), and a second laser emitter (725). The first rangefinder (721) and the second rangefinder (722) are spaced apart along the Z direction. M The second rangefinder (722) and the third rangefinder (723) are separated by a distance along the Y direction. N The first laser emitter (724) is located diagonally opposite the second rangefinder (722), and the second laser emitter (725) is located in the middle of the first laser emitter (724) and the first rangefinder (721). Initially, the positioning plate (72) and the flat plate (425) are parallel to each other in the X direction. The lasers emitted by the first laser emitter (724) and the second laser emitter (725) are respectively aligned with the centers of the first photoelectric sensor (4251) and the second photoelectric sensor (4252). The distances between the first rangefinder (721), the second rangefinder (722), the third rangefinder (723) and the flat plate (425) are respectively... L 1. L 2.L 3 and L 1= L 2= L 3; During operation, assume that the first photoelectric sensor (4251) measures the laser spot offset as (0, N + Δy 1, M + Δz 1) The second photoelectric sensor (4252) measured the offset as (0, N / 2 + Δy 2, M + Δz 2) The distance changes measured by the three rangefinders were as follows: ΔL 1. ΔL 2. ΔL 3. The change in pose of the industrial robot relative to the workpiece to be cleaned is: Y-direction offset:

[0013] Z-direction offset:

[0014] Change in pitch angle α:

[0015] R The distance from the center of the industrial robot base to the first laser emitter (724) is [missing information]. X-direction offset:

[0016] Change in roll angle β:

[0017] Change in yaw angle γ:

[0018] The pose change is input into the control system, which drives the actuators of each axis of the lifting and rotating platform to adjust the position and angle in the X, Y, Z, α, β, and γ directions respectively, so that the relative pose between the industrial robot and the workpiece to be cleaned is restored to the initial state, thereby realizing dynamic compensation of the position of the laser cleaning head.

[0019] In another approach, the industrial robot is directly fixed to an unmanned mobile platform. The aforementioned mechanical contact-type relative position sensing device is used, and a sensor mechanism for acquiring pose offsets in the X, Y, Z, α, β, and γ directions is added to the relative position sensing device. The acquired pose offset is input to the industrial robot's controller, which adjusts its internal coordinate system in real time according to the offset, so that the movement trajectory of the laser cleaning head carried by the end of the industrial robot remains relatively constant with the surface of the workpiece to be cleaned, thereby compensating for pose errors caused by uneven ground.

[0020] In another approach, the industrial robot is directly fixed to an unmanned mobile platform. Using the aforementioned photoelectric non-contact relative position sensing device, the acquired pose offset is input into the industrial robot's controller. The controller adjusts its internal coordinate system in real time according to the offset, so that the movement trajectory of the laser cleaning head carried at the end of the industrial robot remains relatively constant with the surface of the workpiece to be cleaned, thereby compensating for pose errors caused by uneven ground.

[0021] Compared with the prior art, the adaptive positioning device for a laser cleaning system suitable for moving on uneven ground provided by the present invention organically combines an unmanned mobile platform, a high-precision lifting and rotating module and a relative position sensing device, and realizes real-time detection and dynamic compensation of the position and posture error of the cleaning head caused by ground undulation, which significantly improves the operation accuracy and stability of the laser cleaning system under complex terrain conditions.

[0022] Specifically, this invention effectively overcomes the vertical undulations, lateral swaying, unstable forward and backward speeds, and multi-degree-of-freedom pose disturbances such as pitch, roll, and yaw caused by the mobile platform on uneven ground, without relying on additional leveling facilities such as rails or tracks. This avoids the problem of cleaning trajectory deviation and inconsistent cleaning results caused by changes in vehicle posture. By setting up a relative position sensing device to collect the relative pose changes between the cleaning head and the workpiece surface in real time, and combining this with a high-precision lifting and rotating platform or industrial robot controller for precise compensation, this invention can maintain a constant relative position between the cleaning head and the workpiece surface under uneven outdoor or workshop ground conditions, thereby significantly improving the adaptability of the laser cleaning system to complex working environments.

[0023] Furthermore, while maintaining the inherent advantages of laser cleaning, such as non-contact operation, zero damage to substrates, and environmental friendliness with no consumables, this invention further enables flexible movement and precise positioning of the cleaning equipment in a wide range of three-dimensional spaces. The collaborative operation of the unmanned mobile platform and industrial robots, coupled with an integrated control system, makes the entire cleaning process highly automated and traceable. This reduces reliance on manual operation and avoids the efficiency losses caused by frequent equipment adjustments or repositioning due to uneven ground in traditional cleaning methods.

[0024] In summary, this invention improves the adaptability of the laser cleaning system to uneven ground, ensures cleaning accuracy and consistency, and balances operational efficiency and equipment integration, providing a reliable technical solution for high-quality laser cleaning of large structural components under complex working conditions. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0026] Figure 1 This is a schematic diagram of the structure of the laser cleaning system described in this invention; Figure 2 This is a schematic diagram of the adaptive positioning device provided in Embodiment 1 of the present invention; Figure 3 yes Figure 2 Top view from angle AA; Figure 4 This is a schematic diagram of the adaptive positioning device provided in Embodiment 2 of the present invention; Figure 5 yes Figure 4 Top view from the middle BB angle; Figure 6 yes Figure 5 Side view (front view of the flat plate) at the C-angle. Figure 7 yes Figure 5 Side view of the DD angle (main view of the positioning plate); The reference numerals in the attached figures are as follows: 1-Unmanned vehicle, 2-Bearing platform, 3-Sheet metal room, 4-Adaptive positioning device, 5-Industrial robot, 51-Industrial robot base, 6-Laser cleaning head, 7-Workpiece to be cleaned, 71-Positioning feature; 72-Positioning plate, 721-First rangefinder, 722-First rangefinder, 723-First rangefinder, 724-First laser emitter, 725-Second laser emitter; 41-Lifting and Rotating Platform: 411A-X-axis motion guide rail, 411B-X-axis guide rail slider, 411C-X-axis motion platform; 412A-Y-axis motion guide rail, 412B-Y-axis guide rail slider, 412C-Y-axis motion platform; 413A-Z-axis motion guide rail, 413B-Z-axis guide rail slider, 413C-Z-axis motion platform; 414A-γ-axis rotating shaft, 414B-γ-axis rotating shaft bearing; 415A-Spherical shaft, 415B-Spherical shaft bearing; 416-Fixed base; 42-Relative position sensing device: 421-Rod, 422-Frame, 4221-Upper branch, 4222-Lower branch, 423-Wheel set, 424-Magnet; 425-Plate, 4251-First photoelectric sensor, 4252-First photoelectric sensor. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative effort are all within the scope of protection of the present invention.

[0028] This invention provides an adaptive positioning device for a laser cleaning system that can move on uneven ground, such as... Figure 1 As shown, the laser cleaning system includes an unmanned vehicle 1, a sheet metal booth 3, an industrial robot 5, a laser cleaning head 6, and a control system. The unmanned vehicle 1 features automatic navigation and fixed-point docking capabilities, employing a steering wheel-based locomotion system to adapt to diverse and complex terrains. Internally, it integrates a power system, a control system, and a communication module. The power system provides power for vehicle movement and various electrical equipment, while the communication module enables two-way communication between the unmanned vehicle and a remote control console, allowing for remote control of the vehicle's movement and operational status via wireless remote control or a handheld device. The unmanned vehicle's support platform 2 is constructed of high-strength alloy structural steel and features positioning pins and bolt holes for mounting the industrial robot and the sheet metal booth.

[0029] Sheet metal chamber 3 is a sealed structure, featuring dustproof, waterproof, temperature-controlled, and shockproof functions. Internally, it houses equipment such as a laser, chiller, fume purifier, voltage regulator, and control cabinet, all secured with screws. The laser can be either a continuous fiber laser or a pulsed fiber laser, connected to the laser cleaning head via optical fiber, providing a high-energy-density laser beam to meet cleaning operation requirements. The chiller has a constant-temperature control function, connected to the laser and cleaning head via piping to achieve circulating water supply, effectively ensuring the equipment operates within its normal operating temperature range and preventing adverse effects on performance and lifespan due to abnormal temperatures. The fume purifier is a negative-pressure explosion-proof vacuum cleaner, connected to a dust hood near the laser cleaning head via a suction pipe. It collects smoke and dust generated during the cleaning process, purifies them, and then discharges them, avoiding environmental pollution and ensuring a safe working environment.

[0030] Industrial robot 5 is a six-degree-of-freedom articulated robot. Its base is mounted on the platform 2 of the unmanned vehicle via an adaptive positioning device 4. The laser cleaning head 6 is detachably fixed to the robot's end flange. The industrial robot, carrying the laser cleaning head, performs non-contact, adaptive trajectory tracking cleaning on the complex surfaces of large structural components. The laser cleaning head uses galvanometer scanning or rotating mirror scanning, is connected to the laser via fiber optics, and is equipped with a collimating lens, focusing lens, and protective lens. The control system integrates a touchscreen operating interface and connects to the laser, chiller, fume purifier, industrial robot, and other equipment via control signal lines to achieve coordinated control of the entire machine.

[0031] In actual operation, the unmanned vehicle transports the entire system to the vicinity of the workpiece to be cleaned. Due to the unevenness of the working ground, the unmanned vehicle will experience multi-degree-of-freedom pose changes during movement and parking, including up-and-down undulations, left-and-right swaying, pitching, rolling, and yaw. These pose changes are transmitted to the industrial robot and the laser cleaning head, causing a dynamic shift in the relative position between the cleaning head and the surface of the workpiece to be cleaned.

[0032] This invention uses an adaptive positioning device 4 to detect the aforementioned offset in real time and dynamically compensate for it, thereby ensuring a constant relative position between the cleaning head and the workpiece surface and guaranteeing cleaning quality. The structure and compensation method of the adaptive positioning device will be described in detail below with reference to specific embodiments.

[0033] Example 1 like Figure 2 As shown, in this embodiment, the adaptive positioning device 4 includes a high-precision lifting and rotating platform 41 and a relative position sensing device 42. The workpiece 7 to be cleaned has a continuous positioning feature 71 extending along its length.

[0034] The high-precision lifting and rotating platform 41 is fixed on the unmanned vehicle carrier platform 2, and its structure includes: X-axis motion guide rail 411A, X-axis guide rail slider 411B, X-axis motion platform 411C; Y-axis motion guide rail 412A, Y-axis guide rail slider 412B, Y-axis motion platform 412C; Z-axis motion guide rail 413A, Z-axis guide rail slider 413B, Z-axis motion platform 413C; γ shaft 414A and γ shaft bearing 414B, ball shaft 415A and ball shaft bearing 415B containing the ball shaft 415A.

[0035] Ball bearing 415B is fixedly mounted on the unmanned vehicle platform 2 via mounting base 416. Ball bearing 415A can rotate within ball bearing 415B to achieve adaptive adjustment of pitch angle (α) and roll angle (β) under external force. Gamma-axis bearing 414B is fixedly mounted above ball bearing 415A. Gamma-axis bearing 414A can rotate freely within gamma-axis bearing to achieve adaptive adjustment of yaw angle (γ) under external force. Y-axis motion platform 412C is integrated with gamma-axis bearing 414A and fixedly mounted above gamma-axis bearing 414A. Y-axis motion guide rail 412A is fixedly mounted on Y-axis motion platform 412C. Y-axis guide rail slider 412B is provided on Y-axis motion guide rail 412A. Y-axis guide rail slider 412B can slide freely along Y-axis motion guide rail 412A in the Y direction (parallel to the horizontal direction of the paper). The X-axis motion guide rail 411A is fixedly mounted on the Y-axis guide rail slider 412B, and the X-axis motion guide rail 411A is equipped with the X-axis guide rail slider 411B. The X-axis guide rail slider 411B can slide freely along the X-axis motion guide rail 411A in the X direction (perpendicular to the paper plane). The X-axis motion platform 411C is also fixedly mounted on the X-axis guide rail slider 411B. The Z-axis motion guide rail 413A is vertically fixedly mounted on the X-axis motion platform 411C, and the Z-axis motion guide rail 413A is equipped with the Z-axis guide rail slider 413B. The Z-axis guide rail slider 413B can slide freely along the Z-axis motion guide rail 413A in the vertical direction (parallel to the vertical direction of the paper plane). The Z-axis guide rail slider 413B is also fixedly mounted on the Z-axis guide rail slider 413C, which is used to support and fix the industrial robot base 51.

[0036] To maintain structural stability and smooth movement, the Z-axis motion guide rails 413A can be configured as two (or more) parallel and opposite lines. Each Z-axis motion guide rail 413A is equipped with a Z-axis guide rail slider 413B, and the two (or more) Z-axis guide rail sliders 413B are used to fix and connect the Z-axis motion platform 413C. Similarly, the X-axis motion guide rails 411A can also be configured as two (or more) parallel and opposite lines. Each X-axis motion guide rail 411A is equipped with an X-axis guide rail slider 411B, and the two (or more) X-axis guide rail sliders 411B are used to fix and connect the X-axis motion platform 411C. The Y-axis motion guide rails 412A, Y-axis guide rail sliders 412B, and Y-axis motion platform 412C can also be configured in the same way.

[0037] The high-precision lifting and rotating platform 41A described above enables the industrial robot base 51 (industrial robot 5) to generate adaptive motion in six degrees of freedom, namely X, Y, Z linear directions and α, β, γ rotational directions, in order to compensate for the positional changes of the unmanned vehicle 1 caused by uneven ground.

[0038] like Figure 2 and Figure 3As shown, the relative position sensing device 42 includes a rod 421. One end of the rod 421 is fixedly connected to the Z-axis motion platform 413C and maintains a similar height to the industrial robot base 51. The other end of the rod 421 is fixedly connected to two identical frames 422 arranged side by side. Each frame has an upper fork 4221 and a lower fork 4222, and each fork end is equipped with a wheel set 423. The vertical distance between the upper and lower forks can be adjusted according to the thickness of the workpiece positioning feature 71, so that the wheel set 423 can closely fit the upper and lower surfaces of the positioning feature 71. In this embodiment, since the unmanned vehicle 1 moves unstablely in the X direction, the wheel set 423 can be equipped with a drive motor to make the position sensing device 42 move stably in the X-axis direction, thereby pushing the X-axis motion platform 411C forward or backward at a stable speed. Each frame or fork is also provided with a strong magnet 424 to attract the frame to the side of the positioning feature 71, ensuring that the relative position in the Y direction is fixed.

[0039] During operation, when the unmanned vehicle 1 changes its posture due to uneven ground, the posture of the linkage 421 changes with the change of the positioning feature 71. Since the linkage 421 is fixedly connected to the industrial robot base 51, the motion axes of the height lifting and rotating platform 41 are passively adjusted accordingly, thereby keeping the posture of the industrial robot base 51 relatively consistent with the positioning feature 71, thus offsetting the impact of the posture change of the unmanned vehicle 1.

[0040] Example 2 The difference between this embodiment and Embodiment 1 is that the workpiece 7 to be cleaned does not have continuous mechanical positioning features 71, and the relative position sensing device 42 adopts a photoelectric non-contact measurement method. In this embodiment, the structure of the high-precision lifting and rotating platform 41 is the same as that in Embodiment 1, and each axis driver (such as a servo motor) is added to achieve active control.

[0041] like Figures 4-7 As shown, a positioning plate 72, which can be magnetically fixed, is installed on the workpiece 7 to be cleaned. This plate is perpendicular to the workpiece's cleaning surface. The positioning plate 72 is equipped with three rangefinders 721, 722, and 723, and two laser emitters 724 and 725. Rangefinders 721 and 722 are spaced apart along the Z-direction. M The distance between rangefinders 722 and 723 along the Y direction is... N Laser emitter 724 is located diagonally opposite rangefinder 722, and laser emitter 725 is located between laser emitter 724 and rangefinder 721.

[0042] A plate 425 is fixed to the end of the rod 421, and two four-quadrant photoelectric sensors 4251 and 4252 are mounted on the plate. During initial alignment, the plate 425 and the positioning plate 72 are parallel to each other in the X direction. Adjustments are made so that the lasers emitted by the laser emitters 724 and 725 are aligned with the centers of the photoelectric sensors 4251 and 4252, respectively. At this time, the distances between the rangefinders 721, 722, and 723 on the positioning plate 72 and the plate 425 are respectively... L 1. L 2. L 3 and L 1= L 2= L 3. During operation, when the unmanned vehicle 1 changes position due to uneven ground, the flat plate 425 moves along with the rod 421. Assume that the laser spot offset measured by the photoelectric sensor 4251 at this time is (0, ... N + Δ y 1, M + Δz 1) The offset measured by photoelectric sensor 4252 is (0, N / 2 + Δy 2, M + Δz 2). Simultaneously, the distance changes measured by the three rangefinders were respectively... ΔL 1. ΔL 2. ΔL 3.

[0043] The change in pose of the industrial robot base 51 relative to the workpiece 7 can then be calculated using the following formula: Y-direction offset:

[0044] Z-direction offset:

[0045] Change in pitch angle α:

[0046] in, R The distance from the center of the industrial robot base 51 to the laser emitter 724.

[0047] X-direction offset:

[0048] Change in roll angle β:

[0049] Change in yaw angle γ:

[0050] The above calculation results are input into the control system, which drives the drivers of each axis of the high-precision lifting and rotating platform 41 to adjust the position and angle in the X, Y, Z, α, β and γ directions respectively, so that the relative pose between the industrial robot base 51 and the workpiece 7 is restored to the initial state, thereby realizing dynamic compensation of the cleaning head position.

[0051] Example 3 The difference between this embodiment and Embodiment 2 is that the high-precision lifting and rotating platform 41 is omitted, and the industrial robot base 51 is directly fixed to the unmanned vehicle's carrying platform 2. The relative position sensing device 42 still adopts the same mechanical contact structure as Embodiment 1, but a small sensor mechanism capable of measuring X, Y, Z, α, β, and γ degrees of freedom is connected to the end of the rod 421 (this mechanism is similar in structure to the high-precision lifting and rotating platform, but is only used for measurement and not for active compensation). This sensor mechanism is used to detect the relative pose change between the industrial robot base 51 and the workpiece 7 in real time. Alternatively, the relative position sensing device 42 can directly adopt the photoelectric non-contact structure in Embodiment 2 to detect pose changes.

[0052] The obtained pose offset is input into the controller of the industrial robot 5. The controller of the industrial robot 5 adjusts its internal coordinate system in real time according to the offset, so that the motion trajectory of the laser cleaning head 6 carried by the robot end is relatively constant with the workpiece surface, thereby compensating for the pose error caused by uneven ground.

[0053] As can be seen from the above three embodiments, the present invention can flexibly select mechanical contact or photoelectric non-contact relative position sensing methods according to the specific characteristics of the workpiece to be cleaned and the operational requirements. It can also choose to perform physical compensation through a lifting and rotating platform or coordinate compensation through an industrial robot controller, effectively solving the problem of cleaning head posture error caused by uneven ground, and realizing high-precision adaptive positioning of the laser cleaning system under uneven ground conditions.

[0054] It should be noted that the positioning feature 71 refers to a specific structure or mark located on the workpiece 7 to be cleaned, which can be identified, contacted, or detected by the adaptive positioning device 4. The main function of the workpiece feature is to provide a stable spatial reference for the relative position sensing device 42, thereby realizing real-time detection and dynamic compensation of the relative pose changes between the industrial robot base 51 and the workpiece to be cleaned. Specifically, the workpiece feature can take the following two forms depending on the actual situation of the workpiece to be cleaned: Firstly, the inherent geometric structure of the workpiece itself can be used as a positioning feature. For example, in Embodiment 1, the workpiece 7 to be cleaned is a long flat plate with a continuous positioning feature 71 extending along its length. This positioning feature can be an edge, ridge, raised rib, groove, stepped surface, or other continuous and dimensionally stable structural part of the workpiece. As long as this structure maintains a definite spatial position relative to the workpiece cleaning surface during the cleaning process, it can be clamped or attached to the mechanical contact mechanism (such as an upper and lower forked frame with wheels) in the relative position sensing device, thereby serving as a position reference.

[0055] Secondly, when the surface of the workpiece to be cleaned lacks inherent geometric features available for use, a reference feature can be artificially added. For example, in Embodiment 2, a fixed positioning plate 72 is installed on the workpiece, which is perpendicular to the workpiece cleaning surface and serves as a target for a photoelectric sensor or a measuring surface for a rangefinder. This artificially added positioning plate 72 also constitutes a workpiece feature for achieving non-contact position detection. In addition, sensors or mechanical reference blocks attached temporarily by adhesive or magnetic attraction also fall within the scope of workpiece features.

[0056] The workpiece features must meet the following basic requirements: maintain a fixed position relative to the cleaning surface of the workpiece during the cleaning operation; be stably detected by a relative position sensing device (through mechanical contact or photoelectric non-contact methods); and have a definite transformation relationship between its spatial coordinates and the target working position of the industrial robot base. Based on the pose changes detected by the workpiece features, the relative motion error between the industrial robot base and the workpiece surface caused by uneven ground can be inferred, and then compensated by the height-lifting rotary platform or the industrial robot controller.

[0057] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, and there are many other variations of different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An adaptive positioning device for a laser cleaning system suitable for movement on uneven ground, the laser cleaning system comprising an unmanned mobile platform, an industrial robot mounted on the unmanned mobile platform, and a laser cleaning head driven by the industrial robot; characterized in that, The adaptive positioning device is positioned between the laser cleaning system and the workpiece to be cleaned, and is used to detect and dynamically compensate for the relative positional error between the laser cleaning head and the surface of the workpiece to be cleaned caused by unevenness of the working ground in real time.

2. The adaptive positioning device for the laser cleaning system as described in claim 1, characterized in that, include: A relative position sensing device for detecting and responding to changes in the pose of an industrial robot base relative to the surface of a workpiece to be cleaned, and a lifting and rotating platform for adaptively adjusting the pose of the industrial robot base according to the changes in pose. The lifting and rotating platform includes: X-axis motion guide (411A), X-axis guide slider (411B), X-axis motion platform (411C). Y-axis motion guide (412A), Y-axis guide slider (412B), Y-axis motion platform (412C); Z-axis motion guide (413A), Z-axis guide slider (413B), Z-axis motion platform (413C). γ shaft (414A) and γ shaft bearing (414B), ball shaft (415A) and ball shaft bearing (415B). The ball bearing (415B) is fixedly mounted on the unmanned mobile platform. The ball shaft (415A) rotates within the ball bearing (415B) to achieve adaptive adjustment of the pitch angle α and roll angle β under external force. The γ-axis bearing (414B) is fixedly mounted above the ball shaft (415A). The γ-axis (414A) rotates freely within the γ-axis bearing (414B) to achieve adaptive adjustment of the yaw angle γ under external force. The Y-axis motion platform (412C) is integrated with the γ-axis (414A) and fixedly mounted above the γ-axis (414A). The Y-axis motion guide rail (412A) is fixedly mounted on the Y-axis motion platform (412C). A Y-axis guide rail slider (412B) is provided on the Y-axis motion guide rail (412A), and the Y-axis guide rail slider (412B) moves along the Y-axis motion guide rail (412A). The X-axis motion guide rail (411A) is fixedly mounted on the Y-axis guide rail slider (412B), and the X-axis motion guide rail (411A) is provided with an X-axis guide rail slider (411B). The X-axis guide rail slider (411B) slides freely along the X-axis motion guide rail (411A) in the X direction. The X-axis guide rail slider (411B) is also fixedly mounted with an X-axis motion platform (411C). The Z-axis motion guide rail (413A) is vertically fixedly mounted on the X-axis motion platform (411C), and the Z-axis motion guide rail (413A) is provided with a Z-axis guide rail slider (413B). The Z-axis guide rail slider (413B) slides freely along the Z-axis motion guide rail (413A) in the vertical direction. The Z-axis guide rail slider (413B) is also fixedly mounted with a Z-axis motion platform (413C), which is used to support and fix the industrial robot.

3. The adaptive positioning device for the laser cleaning system as described in claim 2, characterized in that, The Z-axis motion guide rail (413A) is configured as two or more parallel and opposite, and each Z-axis motion guide rail (413A) is provided with a Z-axis guide rail slider (413B). The two or more Z-axis guide rail sliders (413B) are used to fix and connect the Z-axis motion platform (413C).

4. The adaptive positioning device for the laser cleaning system as described in claim 2, characterized in that, The X-axis motion guide rail (411A) can be set as two or more parallel and opposite, and an X-axis guide rail slider (411B) is set on each X-axis motion guide rail (411A). The two or more X-axis guide rail sliders (411B) are used to fix the X-axis motion platform (411C).

5. The adaptive positioning device for the laser cleaning system as described in claim 2, characterized in that, The Y-axis motion guide rail (412A) can be set as two or more parallel and opposite, and a Y-axis guide rail slider (412B) is set on each Y-axis motion guide rail (412A). The two or more Y-axis guide rail sliders (412B) are used to fix the Y-axis motion platform (412C).

6. The adaptive positioning device for the laser cleaning system as described in claim 2, characterized in that, The relative position sensing device includes a rod (421), one end of which is fixedly connected to a Z-axis motion platform (413C) or an industrial robot base; the other end of the rod (421) is fixedly connected to a frame (422), the frame (422) is provided with an upper fork (4221) and a lower fork (4222), and each fork end is provided with a wheel set (423); the vertical distance between the upper and lower forks is adjusted according to the thickness of the positioning feature on the workpiece to be cleaned, so that the wheel set (423) fits tightly against the upper and lower surfaces of the positioning feature; the wheel set (423) has a drive motor to make the relative position sensing device move stably in the X-axis direction, thereby driving the X-axis motion platform (411C) to move; a strong magnet (424) is also provided on the frame or fork to attract the frame to the side of the positioning feature, so as to ensure that the relative position in the Y direction is fixed; the positioning feature refers to the structure located on the workpiece to be cleaned for auxiliary positioning, including the geometric structure inherent to the workpiece itself or artificially added.

7. The adaptive positioning device for the laser cleaning system as described in claim 2, characterized in that, Each axis of the lifting and rotating platform is equipped with a driver, which is used to drive the lifting and rotating platform to adjust its posture according to the posture change; The relative position sensing device includes a rod (421), one end of which is fixedly connected to a Z-axis motion platform (413C) or an industrial robot base; the other end of the rod (421) is fixedly connected to a plate (425), on which a first photoelectric sensor (4251) and a second photoelectric sensor (4252) are provided. A positioning plate (72) is vertically fixed on the workpiece to be cleaned. The positioning plate (72) is equipped with a first rangefinder (721), a second rangefinder (722), a third rangefinder (723), a first laser emitter (724), and a second laser emitter (725). The first rangefinder (721) and the second rangefinder (722) are spaced apart along the Z direction. M The second rangefinder (722) and the third rangefinder (723) are separated by a distance along the Y direction. N The first laser emitter (724) is located diagonally opposite the second rangefinder (722), and the second laser emitter (725) is located in the middle of the first laser emitter (724) and the first rangefinder (721). Initially, the positioning plate (72) and the flat plate (425) are parallel to each other in the X direction. The lasers emitted by the first laser emitter (724) and the second laser emitter (725) are respectively aligned with the centers of the first photoelectric sensor (4251) and the second photoelectric sensor (4252). The distances between the first rangefinder (721), the second rangefinder (722), the third rangefinder (723) and the flat plate (425) are respectively... L 1. L 2. L 3 and L 1 = L 2 = L 3; During operation, assume that the first photoelectric sensor (4251) measures the laser spot offset as (0, N + Δy 1, M + Δz 1) The second photoelectric sensor (4252) measured the offset as (0, N / 2 + Δy 2, M + Δz 2) The distance changes measured by the three rangefinders were as follows: ΔL 1. ΔL 2. ΔL 3. The change in pose of the industrial robot relative to the workpiece to be cleaned is: Y-direction offset: Z-direction offset: Change in pitch angle α: R The distance from the center of the industrial robot base to the first laser emitter (724) is [missing information]. X-direction offset: Change in roll angle β: Change in yaw angle γ: The pose change is input into the control system, which drives the actuators of each axis of the lifting and rotating platform to adjust the position and angle in the X, Y, Z, α, β, and γ directions respectively, so that the relative pose between the industrial robot and the workpiece to be cleaned is restored to the initial state, thereby realizing dynamic compensation of the position of the laser cleaning head.

8. The adaptive positioning device for the laser cleaning system as described in claim 1, characterized in that, An industrial robot is directly fixed to an unmanned mobile platform. A relative position sensing device as described in claim 6 is used, and a sensor mechanism for acquiring pose offsets in the X, Y, Z, α, β, and γ directions is added to the relative position sensing device. The acquired pose offset is input to the controller of the industrial robot. The controller adjusts its internal coordinate system in real time according to the offset, so that the movement trajectory of the laser cleaning head carried by the end of the industrial robot remains relatively constant with the surface of the workpiece to be cleaned, thereby compensating for pose errors caused by uneven ground.

9. The adaptive positioning device for the laser cleaning system as described in claim 1, characterized in that, The industrial robot is directly fixed on the unmanned mobile platform. Using the relative position sensing device as described in claim 7, the acquired pose offset is input into the controller of the industrial robot. The controller adjusts its internal coordinate system in real time according to the offset, so that the movement trajectory of the laser cleaning head carried by the end of the industrial robot remains relatively constant with the surface of the workpiece to be cleaned, thereby compensating for the pose error caused by uneven ground.

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