A runner non-destructive testing robot

Abstract

The utility model discloses a kind of rotating wheel nondestructive testing robots, belong to special robot and nondestructive testing technical field, including permanent magnet adsorption walking mechanism, multi-degree-of-freedom mechanical arm, module flaw detection unit, multi-sensor positioning system and central controller;The adsorption walking mechanism is used to realize full attitude stable crawling on rotating wheel camber;Multi-degree-of-freedom mechanical arm is set in permanent magnet adsorption walking mechanism middle upper portion and is used to move module flaw detection unit to specified position;The module flaw detection unit is used for high-resolution detection to rotating wheel on composite material damage;Multi-sensor positioning system is used for the real-time pose feedback of robot;Central controller is used to control each component collaborative work.The rotating wheel nondestructive testing robot of the utility model can effectively solve the detection of the internal crack of the runner blade of the water turbine in the prior art relies on artificial erection mode, there is high-altitude operation risk, many blind areas of detection, low efficiency and other problems.

Description

Technical Field

[0001] This utility model belongs to the field of special robots and non-destructive testing technology. Specifically, it relates to a rotary non-destructive testing robot. Background Technology

[0002] As the core equipment of a hydroelectric power generation system, the turbine runner (especially the mixed-flow runner) operates under complex conditions of high head and strong water flow impact for extended periods. Internal cracks in the blades are prone to develop due to fatigue, stress concentration, and other factors. If these cracks are not detected in time, they may continue to propagate during operation, eventually leading to serious accidents such as blade breakage. This not only affects power generation efficiency but also causes significant economic losses and safety hazards. Therefore, regular and precise non-destructive testing of internal cracks in turbine runner blades is a crucial step in ensuring the safe and stable operation of the unit.

[0003] In current technologies, the detection of internal cracks in turbine runner blades (especially mixed-flow turbines) has long relied on manual scaffolding, which suffers from three major drawbacks: high-altitude operation risks, numerous blind spots, and low efficiency. Existing wall-climbing robots have problems such as insufficient adhesion, poor adaptability to curved surfaces, and inability to integrate multimodal flaw detection equipment. Utility Model Content

[0004] The purpose of this invention is to provide a non-destructive testing robot for turbine runners, addressing the aforementioned shortcomings. This robot solves the problems of existing technologies relying on manual scaffolding for detecting internal cracks in turbine runner blades (especially mixed-flow type), which suffers from high-risk high-altitude operations, numerous blind spots, and low efficiency. To achieve the above objective, this invention provides the following technical solution:

[0005] A rotary wheel non-destructive testing robot includes a permanent magnet adsorption walking mechanism, a multi-degree-of-freedom robotic arm, a modular flaw detection unit, a multi-sensor positioning system, and a central controller. The permanent magnet adsorption walking mechanism is used to achieve stable crawling in all postures on the curved surface of the rotary wheel. The multi-degree-of-freedom robotic arm is located above the middle of the permanent magnet adsorption walking mechanism, and its end is equipped with a detection module mounting platform for connecting the modular flaw detection unit. The multi-degree-of-freedom robotic arm is used to move the modular flaw detection unit to a designated position. The modular flaw detection unit is used for high-resolution detection of composite material damage on the rotary wheel. The multi-sensor positioning system is used for real-time pose feedback of the robot. The central controller is used to control the coordinated operation of the permanent magnet adsorption walking mechanism, the multi-degree-of-freedom robotic arm, the modular flaw detection unit, and the multi-sensor positioning system.

[0006] Furthermore, the permanent magnet adsorption walking mechanism includes a base, a permanent magnet adsorption array, and a drive track; the drive track is arranged on both sides of the base and works in conjunction with the permanent magnet adsorption array to achieve stable crawling on the curved surface of the rotating wheel.

[0007] Furthermore, the multi-degree-of-freedom robotic arm includes a base, a first arm body, a second arm body, and a third arm body, as well as five joints that are sequentially connected to the base, the first arm body, the second arm body, the third arm body, and the detection module mounting platform, of which three are rotary joints and two are kinetic joints;

[0008] The rotary joint includes a rotary shaft, a bearing assembly, and a rotary drive component. The axial direction of the rotary shaft is perpendicular to the relative motion plane of the two correspondingly connected components. The rotary drive component can drive the rotary shaft to rotate around its own axis, thereby realizing the relative rotation between two adjacent components.

[0009] The movable joint includes a guide rail assembly, a slider, and a linear drive. The guide rail assembly is fixed to one of the components along a preset linear direction. The slider is fixedly connected to the other component and slides with the guide rail assembly. The linear drive can drive the slider to move along the length of the guide rail assembly, realizing relative linear movement between two adjacent components. The working space of the detection module mounting platform covers a pitch angle of ±180 degrees, and the end-positioning accuracy is ±0.5mm.

[0010] Furthermore, the module flaw detection unit includes a phased array ultrasonic probe, an eddy current probe, and a coupling agent spraying device. The phased array ultrasonic probe consists of multiple piezoelectric crystals arranged in a regular pattern. By controlling the delay time of ultrasonic waves emitted by each crystal, an overall wavefront is formed, enabling the device to scan, deflect, and focus the sound beam. High-resolution detection of composite material damage is achieved through multimodal imaging technology. The eddy current probe monitors key parameters such as axial displacement and axial vibration of the equipment in real time by measuring the relative position or motion state between the probe and the rotating wheel. The coupling agent fills the tiny gaps between the metal surface and the probe, eliminating the reflection and scattering of ultrasonic waves by air, allowing sound waves to enter the metal more smoothly and reducing the impact of acoustic impedance on the inspection results.

[0011] Furthermore, the multi-sensor positioning system integrates an encoder, an IMU inertial unit, a laser rangefinder, and a vision camera for real-time pose feedback.

[0012] Furthermore, the central controller includes a built-in path planning algorithm module and a defect feature extraction module.

[0013] Furthermore, the permanent magnet adsorption array adopts a Halbach magnet structure with a magnetic flux density ≥0.8T and an adsorption safety factor ≥3.0.

[0014] Furthermore, the path planning algorithm module is based on the wheel B-rep model and uses an adaptive grid method to generate collision-free detection trajectories, with the trajectory point density adjustable in the range of 5-20mm.

[0015] Furthermore, the defect feature extraction module performs wavelet packet denoising on the PAUT signal and implements real-time crack type classification based on the YOLOv5 architecture.

[0016] A method for using a rotary non-destructive testing robot, employing the aforementioned rotary non-destructive testing robot, includes the following steps:

[0017] S1. Load the rotary wheel CAD model and divide the detection area;

[0018] S2. Generate a Zigzag scan path covering all blades;

[0019] S3. The robot moves along the path, and the multi-degree-of-freedom robotic arm dynamically adjusts the attitude of the phased array ultrasonic probe to maintain normal coupling.

[0020] S4. The multi-sensor positioning system integrates positioning and constructs a detection map in real time;

[0021] S5. Extract defect features and generate a 3D digital report.

[0022] The beneficial effects of this utility model are:

[0023] This utility model discloses a turbine runner flaw detection robot and method, including a permanent magnet adsorption walking mechanism, a force-controlled multi-degree-of-freedom robotic arm, a modular flaw detection unit, and a multi-sensor positioning system. Strong adsorption is achieved through a Halbach magnetic array (a magnetic structure, an approximately ideal engineering structure, aiming to generate the strongest magnetic field with the minimum amount of magnets), the robotic arm dynamically maintains the normal coupling of the probe, and millimeter-level defect location is achieved by combining fusion positioning technology. This solves the industry problems of incomplete detection coverage and low efficiency in the confined space of turbine runners, and is particularly suitable for automated detection of internal defects in turbine runner blades. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0025] Figure 2 This is a three-dimensional structural schematic diagram of the present invention from another perspective;

[0026] Figure 3 This is a partially exploded structural diagram of the present invention;

[0027] Figure 4 This is an exploded structural diagram of another part of this utility model;

[0028] In the attached diagram: 1. Permanent magnet adsorption walking mechanism; 2. Drive track; 3. Permanent magnet adsorption array; 4. Multi-degree-of-freedom robotic arm; 5. Detection module mounting platform; 7. Phased array ultrasonic probe; 8. Eddy current probe; 9. Coupling agent spraying device; 10. Multi-sensor positioning system; 11. Encoder; 12. IMU inertial unit; 13. Laser rangefinder; 14. Vision camera; 15. Central controller; 16. Path planning algorithm module; 17. Defect feature extraction module. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the present invention is not limited to the following embodiments.

[0030] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0031] In the description of this utility model, "first feature" and "second feature" may include one or more of the features.

[0032] In the description of this utility model, "multiple" means two or more.

[0033] In the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0034] In the description of this utility model, the terms "above", "over" and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0035] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above 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 one or more embodiments or examples.

[0036] Example

[0037] See attached Figures 1-4 This embodiment discloses a non-destructive testing robot for turbine runners, suitable for composite material damage detection in large turbine runners such as water turbines and steam turbines, especially for turbine blades with curved surfaces, enabling fully automated and high-precision non-destructive testing. The robot consists of five main parts: a permanent magnet adsorption walking mechanism 1, a multi-degree-of-freedom robotic arm 4, a modular flaw detection unit, a multi-sensor positioning system 10, and a central controller 15. These parts work together to complete the turbine runner inspection task. The permanent magnet adsorption walking mechanism 1 serves as the robot's mobile carrier, providing overall support and mobility; the multi-degree-of-freedom robotic arm 4 is responsible for accurately delivering the inspection device to the inspection position; the modular flaw detection unit performs specific damage detection operations; the multi-sensor positioning system 10 provides real-time feedback on the robot's position and attitude; and the central controller 15 acts as the "brain," coordinating and controlling the operation of all components.

[0038] In this embodiment, the permanent magnet adsorption walking mechanism 1 includes a base, a permanent magnet adsorption array 3, and a drive track 2. The base is made of high-strength aluminum alloy and has a flat rectangular structure, providing a mounting base for other components. The permanent magnet adsorption array 3 is embedded in the bottom of the base and uses a Halbach magnet structure arrangement. A special magnet arrangement enhances the magnetic field strength on one side, achieving a magnetic flux density of over 0.8T. This ensures sufficient adsorption force on vertical or inclined rotating surfaces, with an adsorption safety factor of no less than 3.0, effectively preventing the robot from slipping. The drive track 2 is symmetrically arranged on both sides of the base, with a high-friction coefficient rubber surface, working in conjunction with the permanent magnet adsorption array 3 to achieve reliable walking. The drive track 2 is driven by a servo motor, with the speed adjusted by a reducer to meet the needs of different detection speeds.

[0039] In this embodiment, the multi-degree-of-freedom robotic arm 4 is mounted on a base above the middle of the permanent magnet adsorption walking mechanism 1. It consists of a base, a first arm body, a second arm body, a third arm body, and a detection module mounting platform 5. Each component is connected in sequence through five joints, three of which are rotary joints and two are locating joints.

[0040] The rotary joint consists of a rotary shaft, a bearing assembly, and a rotary drive component. The rotary shaft is made of 45# steel, and its surface is hardened to enhance wear resistance. The bearing assembly uses high-precision crossed roller bearings to ensure rotational accuracy. The rotary drive component uses a servo motor, which is connected to the rotary shaft through a harmonic reducer, enabling precise rotation of the rotary shaft around its own axis. The relative rotation angle range between adjacent components can reach 0-360 degrees.

[0041] The movable joint comprises a guide rail assembly, a slider, and a linear drive component. The guide rail assembly uses a high-precision linear guide rail, which is fixed to the arm body along a preset straight line. The slider is fixedly connected to the adjacent arm body and forms a sliding engagement with the guide rail assembly. The linear drive component uses a ball screw and nut mechanism, with the screw arranged parallel to the guide rail assembly and the nut rigidly connected to the slider. A servo motor drives the screw to rotate, causing the slider to move along the guide rail, thus achieving relative linear motion between adjacent components.

[0042] Through the coordinated movement of each joint, the working space of the detection module mounting platform 5 can cover a pitch angle of ±180 degrees, and the end-positioning accuracy reaches ±0.5mm. It can flexibly adjust the posture of the detection device to ensure that it maintains the best detection angle with the surface of the rotating wheel.

[0043] In this embodiment, the modular flaw detection unit is mounted on the detection module mounting platform 5 and includes a phased array ultrasonic probe 7, an eddy current probe 8, and a coupling agent spraying device 9. The phased array ultrasonic probe 7 is composed of multiple piezoelectric crystals arranged in a linear array or other regular pattern. The delay time of the ultrasonic waves emitted by each crystal is controlled by the central controller 15, which can form an adjustable overall wavefront, realizing electronic scanning, deflection, and focusing of the sound beam, and completing a large-area detection without mechanical movement. This probe adopts multimodal imaging technology and can simultaneously acquire multiple images such as B-scan and C-scan, achieving high-resolution detection of damage such as delamination and cracks in composite materials.

[0044] The eddy current probe 8 adopts a high-frequency coil design, with a working frequency selectable from 100kHz to 1MHz. By measuring the change in the electromagnetic field between the probe and the surface of the rotor, it can monitor parameters such as shaft displacement and shaft vibration of the equipment in real time, and help to judge the flatness and minor defects of the rotor surface.

[0045] The coupling agent spraying device 9 is used in conjunction with the phased array ultrasonic probe 7 and includes a coupling agent storage tank, a micro pump, and an atomizing nozzle. During operation, the micro pump draws the coupling agent from the storage tank and sprays it evenly in a mist form onto the detection area through the atomizing nozzle. The coupling agent is made of water-soluble polymer gel material, which can quickly fill the tiny gaps between the metal surface and the probe, eliminate the reflection and scattering of ultrasonic waves by air, reduce the influence of acoustic impedance, and ensure that ultrasonic waves can smoothly enter the interior of the metal.

[0046] In this embodiment, the multi-sensor positioning system 10 integrates an encoder 11, an IMU (Inertial Measurement Unit), a laser rangefinder 13, and a vision camera 14 to achieve real-time pose feedback for the robot. The encoder 11 calculates the walking distance by recording the number of rotations of the motor driving the track 2; the IMU 12 includes a three-axis accelerometer and a three-axis gyroscope, which can measure the robot's acceleration and angular velocity in real time and calculate attitude information; the laser rangefinder 13 is installed at the front end of the base and measures the distance to the surface of the rotating wheel by emitting a laser beam to assist in determining the surface curvature; the vision camera 14 can be an industrial-grade CCD camera equipped with a wide-angle lens to capture feature points on the rotating wheel surface, and combines this with image recognition algorithms to achieve positioning. Multi-sensor data can be fused using a Kalman filter algorithm to improve positioning accuracy.

[0047] In this embodiment, the central controller 15 can be an industrial-grade embedded computer, equipped with a multi-core processor and high-speed storage module, and installed with a real-time operating system. Its built-in path planning algorithm module 16 and defect feature extraction module 17 communicate with other components via data lines. The path planning algorithm module 16 can load the B-rep model of the rotating wheel, use an adaptive grid method to divide the detection area, and generate a collision-free detection trajectory based on the wheel's surface features. The trajectory point density can be adjusted within the range of 5-20mm according to the detection accuracy requirements. After receiving the PAUT signal acquired by the phased array ultrasonic probe 7, the defect feature extraction module 17 first performs wavelet packet denoising to remove noise interference, and then analyzes the processed signal based on the YOLOv5 architecture to achieve real-time classification of crack types.

[0048] The specific steps for using this rotary non-destructive testing robot are as follows:

[0049] S1. Load the rotary wheel CAD model and divide the detection area;

[0050] The operator imports the CAD model of the rotor into the central controller 15 via the host computer. The central controller 15 automatically divides the detection area according to the geometric features of the model. The size of each area can be set according to the actual detection requirements to ensure that all parts of the rotor to be detected are covered, especially key structures such as blades.

[0051] S2. Generate a Zigzag scan path covering all blades;

[0052] The path planning algorithm module 16 generates a zigzag scanning path based on the divided detection area and the B-rep model of the rotor. This path ensures that the detection device covers all blades with an optimal trajectory. The spacing between path points can be adjusted within the range of 5-20mm according to the detection accuracy requirements, while avoiding obstacles such as protrusions on the rotor to ensure collision-free operation.

[0053] S3. The robot moves along the path, and the robotic arm dynamically adjusts the probe's attitude to maintain normal coupling.

[0054] The central controller 15 controls the permanent magnet adsorption walking mechanism 1 to move along the generated scanning path. During the movement, the multi-sensor positioning system 10 collects the robot's pose information in real time and feeds it back to the central controller 15. Based on the feedback information, the central controller 15 controls the movement of each joint of the multi-degree-of-freedom robotic arm 4 to dynamically adjust the posture of the detection module mounting platform 5, ensuring that the phased array ultrasonic probe 7 always maintains normal coupling with the surface of the rotating wheel, thus ensuring the stability of the detection signal. At the same time, the coupling agent spraying device 9 automatically sprays coupling agent according to the detection progress.

[0055] S4. Multi-sensor fusion positioning and real-time construction of detection maps;

[0056] During the inspection process, the encoder 11, IMU inertial unit 12, laser rangefinder 13, and vision camera 14 work simultaneously. The multi-sensor positioning system 10 fuses the data from each sensor to determine the robot's precise position in real time. The inspection data collected by the phased array ultrasonic probe 7 and eddy current probe 8 are transmitted to the central controller 15. The central controller 15 combines the positioning information to construct a real-time inspection map of the wheel, which can intuitively display the damage distribution in the inspection area.

[0057] S5. Extract defect features and generate a 3D digital report;

[0058] After the inspection is completed, the defect feature extraction module 17 processes the acquired PAUT signal to extract feature information such as the location, size, and type of the defect. The central controller 15 combines this information with the three-dimensional model of the wheel to generate a three-dimensional digital inspection report. The report includes the three-dimensional coordinates, image, and classification results of the defect, which facilitates subsequent analysis and evaluation by the operator.

[0059] Through the above structure and method, the rotary non-destructive testing robot can adapt to the curved surface structure of the rotary wheel, realize fully automated and high-precision non-destructive testing, greatly improve testing efficiency and accuracy, and reduce the labor intensity and safety risks of manual testing.

[0060] The above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model. Technologies, shapes, and structural parts not described in detail in this utility model are all known technologies.

Claims

1. A rotary non-destructive testing robot, characterized in that: The system includes a permanent magnet adsorption walking mechanism (1), a multi-degree-of-freedom robotic arm (4), a module flaw detection unit, a multi-sensor positioning system (10), and a central controller (15). The permanent magnet adsorption walking mechanism (1) is used to achieve stable crawling in all postures on the curved surface of the rotating wheel. The multi-degree-of-freedom robotic arm (4) is located above the middle of the permanent magnet adsorption walking mechanism (1), and its end is equipped with a detection module mounting platform (5) for connecting the module flaw detection unit. The multi-degree-of-freedom robotic arm (4) is used to move the module flaw detection unit to a designated position. The module flaw detection unit is used for high-resolution detection of composite material damage on the rotating wheel. The multi-sensor positioning system (10) is used for real-time pose feedback of the robot. The central controller (15) is used to control the permanent magnet adsorption walking mechanism (1), the multi-degree-of-freedom robotic arm (4), the module flaw detection unit, and the multi-sensor positioning system (10) to work together.

2. The rotary non-destructive testing robot according to claim 1, characterized in that: The permanent magnet adsorption walking mechanism (1) includes a base, a permanent magnet adsorption array (3) and a drive track (2); the drive track (2) is arranged on both sides of the base and works with the permanent magnet adsorption array (3) to achieve stable crawling on the rotating wheel surface.

3. The rotary non-destructive testing robot according to claim 2, characterized in that: The multi-degree-of-freedom robotic arm (4) includes a base, a first arm body, a second arm body and a third arm body, and five joints that are sequentially connected to the base, the first arm body, the second arm body, the third arm body and the detection module mounting platform (5), of which three are rotary joints and two are kinetic joints; The rotary joint includes a rotary shaft, a bearing assembly, and a rotary drive component. The axial direction of the rotary shaft is perpendicular to the relative motion plane of the two correspondingly connected components. The rotary drive component can drive the rotary shaft to rotate around its own axis, thereby realizing the relative rotation between two adjacent components. The movable joint includes a guide rail assembly, a slider, and a linear drive. The guide rail assembly is fixed to one of the components along a preset straight line direction. The slider is fixedly connected to the other component and slides with the guide rail assembly. The linear drive can drive the slider to move along the length direction of the guide rail assembly, realizing relative linear movement between two adjacent components. The working space of the detection module mounting platform (5) covers a pitch angle of ±180 degrees and the end positioning accuracy is ±0.5mm.

4. The rotary non-destructive testing robot according to claim 3, characterized in that: The module flaw detection unit includes a phased array ultrasonic probe (7), an eddy current probe (8), and a coupling agent spraying device (9). The phased array ultrasonic probe (7) consists of multiple piezoelectric crystals arranged in a regular pattern. By controlling the delay time of ultrasonic waves emitted by each crystal, an overall wavefront is formed, which realizes the device of sound beam scanning, deflection, and focusing. High-resolution detection of composite material damage is achieved through multimodal imaging technology. The eddy current probe (8) monitors the key parameters of the equipment's axial displacement and axial vibration in real time by measuring the relative position or motion state between the probe and the rotating wheel. The coupling agent fills the tiny gaps between the metal surface and the probe, eliminating the reflection and scattering of ultrasonic waves by air, allowing the sound waves to enter the metal more smoothly and reducing the influence of acoustic impedance on the inspection results.

5. The rotary non-destructive testing robot according to claim 4, characterized in that: The multi-sensor positioning system (10) integrates an encoder (11), an IMU inertial unit (12), a laser rangefinder (13), and a vision camera (14) for real-time pose feedback.

6. The rotary non-destructive testing robot according to claim 5, characterized in that: The central controller (15) includes a built-in path planning algorithm module (16) and a defect feature extraction module (17).

7. A rotary non-destructive testing robot according to claim 6, characterized in that: The permanent magnet adsorption array (3) adopts a Halbach magnet structure with a magnetic flux density ≥0.8T and an adsorption safety factor ≥3.

0.

8. A rotary non-destructive testing robot according to claim 7, characterized in that: The path planning algorithm module (16) is based on the wheel B-rep model and uses the adaptive grid method to generate a collision-free detection trajectory. The trajectory point density can be adjusted in the range of 5-20mm.

9. A rotary non-destructive testing robot according to claim 8, characterized in that: The defect feature extraction module (17) performs wavelet packet denoising on the PAUT signal and implements real-time crack type classification based on the YOLOv5 architecture.

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