A hexapod adsorption robot for offshore wind turbine blade inspection and its control method

Abstract

This invention provides a six-legged adsorption robot and its control method for inspecting offshore wind turbine blades. The robot comprises a double-layered body structure and a biomimetic single-leg structure. The double-layered body structure includes an upper and lower body, each equipped with a motion control system and a vacuum adsorption system. The vacuum adsorption system, in conjunction with a three-step gait, achieves alternating adsorption and vacuum breaking. The motion control system coordinates the robot's walking, turning, posture adjustment, and adsorption functions. The biomimetic single-leg structure includes a thigh, a middle leg, and a lower leg, corresponding to the hip, knee, and ankle joints, respectively. Each leg has three rotational degrees of freedom driven by a servo motor. Springs at the upper and lower parts of the lower leg are compressed to provide preload. The lower leg end is connected to a vacuum suction cup via a fisheye bearing, reducing the impact of landing and providing a passive rotational degree of freedom to adapt to stable adsorption on surfaces with varying curvature. This invention features lightweight structure, strong adaptability to surfaces with varying curvature, high control precision, and safety and reliability.

Description

Technical Field

[0001] This invention relates to the field of intelligent operation and maintenance technology for offshore wind power facilities, and more particularly to a hexapod adsorption robot and control method for detecting offshore wind turbine blades. Background Technology

[0002] Offshore wind turbine blades, as key components of wind turbine generators, are exposed to harsh marine environments for extended periods, enduring complex conditions such as wind loads, salt spray corrosion, and sand and gravel impacts. This makes them prone to surface cracks, coating peeling, and structural damage. If these damages are not detected and repaired in a timely manner, they can lead to decreased aerodynamic performance, shortened fatigue life, and even major safety accidents such as breakage. Currently, the inspection and maintenance of wind turbine blades mainly rely on manual climbing or suspended platform operations, which are not only inefficient but also limited by the safety risks of high-altitude operations and weather conditions, making it difficult to meet the needs of large-scale offshore wind farm development.

[0003] In existing technologies, wall-climbing robots have been attempted for blade inspection tasks, but they generally suffer from insufficient adaptability. Traditional wheeled or tracked robots struggle to achieve stable adhesion and movement on blade surfaces with varying curvature, while robots with single or multiple suction cups face drawbacks such as uneven adhesion force distribution and poor motion flexibility. Furthermore, existing robots mostly employ preset path inspection modes, failing to dynamically adjust their operational strategies based on the actual damage to the blade, resulting in low inspection coverage and numerous repetitive paths. While hexapod bionic structures theoretically possess the advantage of multiple degrees of freedom, existing designs still lack systematic optimization in areas such as the dynamic fit between the foot-end adhesion mechanism and the blade's curved surface, gait planning, and load distribution, thus limiting their reliability and inspection efficiency on complex curved surfaces. Summary of the Invention

[0004] To address the needs of offshore wind turbine blade inspection and maintenance, this invention provides a six-legged adsorption robot and its control method. The robot adopts a biomimetic structure, with flexible design of the lower legs, and combines the passive joints at the foot ends with a vacuum adsorption system, enabling the robot to stably crawl on the surface of variable curvature blades and perform precise inspection operations.

[0005] The technical means employed in this invention are as follows: A six-legged adsorption robot for inspecting offshore wind turbine blades includes: a double-layered fuselage structure and six identical biomimetic single-leg structures, wherein: The double-layer fuselage structure includes an upper fuselage and a lower fuselage. The upper mounting plane of the upper fuselage is equipped with a motion control system, and the lower mounting plane of the lower fuselage is equipped with a vacuum adsorption system. Wherein: The motion control system includes an STM32F407 main control chip, a serial bus servo drive module, an inertial measurement unit (IMU), a relay control module, and a host computer communication interface. The STM32F407 main control chip uses the FreeRTOS multitasking system to schedule motion control tasks, adsorption control tasks, attitude adjustment tasks, and information transmission tasks to achieve stable crawling, turning, and inspection operations of the robot on the surface of the variable curvature blade. The vacuum adsorption system includes a vacuum pump, a reversing valve, an air pipe connector, a connector, a vacuum suction cup, a pressure sensor, and connecting pipes. The vacuum pump is connected to the air inlet of the reversing valve through the air pipe connector and connector. The working port of the reversing valve is connected to the vacuum suction cup through a pipe. The pressure sensor is connected in series between the reversing valve and the vacuum suction cup to detect the negative pressure value in real time and feed it back to the STM32F407 main control chip. The vacuum suction cup is connected to the lower end of the lower leg through a fisheye bearing, giving the suction cup a passive rotational degree of freedom. The six identical bionic single-leg structures are each composed of a thigh, a middle leg, and a lower leg connected in series. The thigh is hinged to the upper fuselage via a first servo motor and a servo disc to form a hip joint. The middle leg is hinged to the thigh via a second servo motor to form a knee joint. The lower leg is hinged to the middle leg via a third servo motor to form an ankle joint.

[0006] Furthermore, the upper fuselage and the lower fuselage are fixedly connected as an integral frame by a front cover, a front support plate, a side support plate, and a rear cover, wherein: The lower end of the front support plate is threaded to the front end of the lower body, and the left and right sides are threaded to the front ends of the left and right support plates respectively, forming a three-dimensional triangular reinforcement structure at the front of the frame. The upper edge of the side support plate is threaded to the side beam of the upper fuselage, and the lower edge is threaded to the side beam of the lower fuselage, extending along the entire length of the fuselage to form continuous load-bearing beams on the left and right sides. The rear end cover is threadedly connected to the rear end of the upper body, the rear end of the lower body, and the rear end of the side support plates to form a closed cavity at the tail of the robot. The front cover, front support plate, side support plate and rear cover together form a complete fuselage protection structure.

[0007] Furthermore, the lower leg is composed of an upper part and a lower part, which are flexibly connected by a spring and locked with a fastening nut at the upper end; the end of the lower part is connected to a vacuum suction cup via a connector, a suction cup joint and a fisheye bearing to form a passive attitude adjustment mechanism to adapt to the blade surface.

[0008] Furthermore, the vacuum adsorption system adopts an independent control loop, including a vacuum pump, two pressure sensors and two reversing valves, which control three vacuum suction cups respectively. When the robot is working, one set of suction cups maintains the adsorption state, while the other set of suction cups is in the vacuum breaking state, which is coordinated with the robot's three-three gait to ensure that there are always three suction cups reliably adsorbing during the movement.

[0009] Furthermore, the STM32F407 main control chip controls the relay control module through the GPIO port, thereby driving the reversing valve to switch between the adsorption state and the vacuum breaking state, so that the robot walks in a three-three gait, that is, at any given time, at least three legs are in the support phase and generate adsorption force.

[0010] Furthermore, the first, second, and third servos are all serial bus servos and are uniformly controlled by the STM32F407 main control chip.

[0011] Furthermore, the inertial measurement unit (IMU) is fixed in the center area of ​​the upper mounting plane of the fuselage. It is used to collect the three-axis attitude angle and acceleration data of the fuselage in real time and feed them back to the STM32F407 main control chip. The attitude adjustment task dynamically adjusts the angle of each joint servo motor according to the feedback data to maintain the fuselage level and conform to the blade surface.

[0012] The present invention also provides a control method based on the above-mentioned hexapod adhesive robot, comprising: S1. Motion commands are generated through a host computer or autonomous path planning and transmitted to the STM32F407 main control chip; The S2 and STM32F407 main control chips are based on the FreeRTOS multi-task system to schedule motion control tasks, calculate inverse kinematics solutions, and output control signals to the serial bus servo motor to realize coordinated movement of each joint of a single leg. S3. Synchronously schedule the adsorption control task. According to the gait phase, control the on and off of the relay through the GPIO port, and then control the operation of the directional valve to realize the vacuum breaking of the swing phase and the vacuum pumping of the support phase. S4. Synchronous scheduling of attitude adjustment tasks: The inertial measurement unit (IMU) monitors the body attitude in real time and feeds it back to the STM32F407 main control chip to adjust the movement of each joint to maintain overall balance and adapt to the slope. S5. Throughout the entire motion process, the inertial measurement unit (IMU) continuously feeds back the three-axis attitude angles and acceleration data of the robot body to the STM32F407 main control chip via the internal bus. Based on this feedback information, the attitude adjustment task fine-tunes the motion angles of each servo motor to compensate for changes in the blade surface or external interference, ensuring the stability of the robot body's attitude. S6. Repeat steps S2-S5 to achieve stable crawling, turning and inspection operations of the robot on the surface of the wind turbine blade.

[0013] Furthermore, the FreeRTOS multitasking system divides functions into independent tasks, which are scheduled by a task scheduler. The tasks include: straight-line movement tasks, turning movement tasks, attitude adjustment tasks, hill climbing and adsorption tasks, and information transmission tasks. Synchronization and data sharing between tasks are achieved through message queues and semaphores.

[0014] Compared with the prior art, the present invention has the following advantages: 1. This invention adopts a design that combines a biomimetic leg structure with a vacuum adsorption system. It achieves flexible movement through a three-degree-of-freedom flexible leg mechanism. Combined with the passive posture adjustment capability provided by the fisheye bearing, it effectively adapts to the complex curved surface shape of wind turbine blades, solving the shortcomings of existing robots in terms of adaptability and stability to variable curvature surfaces.

[0015] 2. This invention uses a group-controlled vacuum adsorption system to divide the six suction cups into two groups for independent control, which are precisely coordinated with the robot's three-three gait to achieve dynamic distribution and maintenance of adsorption force during movement, greatly improving the safety and reliability of the robot when working at heights.

[0016] 3. Based on the STM32F407 main control chip, this invention constructs a multi-task collaborative control system, realizing efficient scheduling and execution of functions such as motion control, adsorption management, and attitude adjustment, thereby improving the real-time performance and stability of the system.

[0017] 4. This invention adopts a modular design concept, dividing the robot into three independent modules: body, legs, and pneumatic system. This not only facilitates maintenance and replacement, but also reduces the overall weight through lightweight design, making it more suitable for high-altitude operations.

[0018] Based on the above reasons, this invention can be widely applied in fields such as offshore wind turbine blade inspection and maintenance. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the six-legged adsorption robot of the present invention.

[0021] Figure 2 This is a schematic diagram of the single-leg structure of the six-legged adsorption robot of the present invention.

[0022] Figure 3This is a schematic diagram of the lower leg structure of the six-legged adsorption robot of the present invention.

[0023] Figure 4 This is a circuit diagram of the vacuum adsorption system of the six-legged adsorption robot of the present invention.

[0024] In the diagram: 1. Upper fuselage; 2. Front cover; 3. Single-leg structure; 4. Upper components; 5. Front support plate; 6. Lower fuselage; 7. Lower components; 8. Side support plate; 9. Rear cover; 10. First servo; 11. Servo disc; 12. Thigh; 13. Second servo; 14. Middle leg; 15. Third servo; 16. Lower leg; 17. Upper fastening nut; 18. Spring; 19. Air pipe connector; 20. Connector; 21. Suction cup; 22. Suction cup connector; 23. Fisheye bearing; 24. Lower part of lower leg; 25. Upper part of lower leg. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0028] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0029] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not 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 on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0030] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0031] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0032] like Figure 1As shown, this invention provides a six-legged adsorption robot for inspecting offshore wind turbine blades, comprising: a double-layered body structure and six identical biomimetic single-leg structures 3. The double-layered body structure not only provides ample installation space but also reduces the overall weight through lightweight design, meeting the requirements for high-altitude operations. The double-layer fuselage structure includes an upper fuselage 1 and a lower fuselage 6. The upper mounting plane of the upper fuselage 1 is equipped with a motion control system 4, and the lower mounting plane of the lower fuselage 6 is equipped with a vacuum adsorption system 7. Wherein: The motion control system 4 includes an STM32F407 main control chip, a serial bus servo drive module, an inertial measurement unit (IMU), a relay control module, and a host computer communication interface. The STM32F407 main control chip performs multi-task scheduling of motion control tasks, adsorption control tasks, attitude adjustment tasks, and information transmission tasks through the FreeRTOS multi-task system to achieve stable crawling, turning, and detection operations of the robot on the surface of the variable curvature blade. The vacuum adsorption system 7 includes a vacuum pump, a reversing valve, an air pipe connector 19, a connector 20, a vacuum suction cup 21, a pressure sensor, and connecting pipes. The vacuum pump is connected to the air inlet of the reversing valve through the air pipe connector 19 and the connector 20. The working port of the reversing valve is connected to the vacuum suction cup 21 through the pipes. The pressure sensor is connected in series between the reversing valve and the vacuum suction cup 21 to detect the negative pressure value in real time and feed it back to the STM32F407 main control chip. The vacuum suction cup 21 is connected to the end of the lower leg 24 through the fisheye bearing 23, so that the suction cup 21 has a passive rotational degree of freedom. like Figure 2 As shown, the six identical bionic single-leg structures 3 are each composed of a thigh 12, a middle leg 14, and a lower leg 16 connected in series. The thigh 12 is hinged to the upper fuselage 1 via a first servo motor 10 and a servo disc 11 to form a hip joint. The middle leg 14 is hinged to the thigh 12 via a second servo motor 13 to form a knee joint. The lower leg 16 is hinged to the middle leg 14 via a third servo motor 15 to form an ankle joint.

[0033] In a specific implementation, as a preferred embodiment of the present invention, the upper fuselage 1 and the lower fuselage 6 are fixedly connected as an integral frame by a front end cover 2, a front support plate 5, a side support plate 8, and a rear end cover 9, wherein: The lower end of the front support plate 5 is threaded to the front end of the lower body 6, and the left and right sides are threaded to the front ends of the left and right support plates 8 respectively, forming a three-dimensional triangular reinforcement structure at the front of the frame. The upper edge of the side support plate 8 is threaded to the side beam of the upper fuselage 1, and the lower edge is threaded to the side beam of the lower fuselage 6, extending along the entire length of the fuselage to form continuous load-bearing beams on the left and right sides. The rear end cover 9 is threadedly connected to the rear end of the upper body 1, the rear end of the lower body 6, and the rear end of the two side support plates 8 to form a closed cavity at the tail of the robot. The front cover 2, front support plate 5, side support plate 8 and rear cover 9 together form a complete fuselage protection structure.

[0034] In specific implementation, as a preferred embodiment of the present invention, such as Figure 3 As shown, the lower leg 16 is composed of an upper lower leg 25 and a lower lower leg 24. The upper lower leg 25 and the lower lower leg 24 are flexibly connected by a spring 18 and locked with an upper fastening nut 17. The end of the lower lower leg 24 is connected to a vacuum suction cup 21 via a connector 20, a suction cup connector 22 and a fisheye bearing 23 to form a passive attitude adjustment mechanism to adapt to the blade surface.

[0035] In specific implementation, as a preferred embodiment of the present invention, such as Figure 4 As shown, the vacuum adsorption system 7 adopts an independent control loop, including a vacuum pump, two pressure sensors and two reversing valves, which control three vacuum suction cups 21 respectively. When the robot is working, one group of suction cups maintains the adsorption state, while the other group of suction cups is in the vacuum breaking state, which is coordinated with the robot's three-three gait to ensure that there are always three suction cups reliably adsorbing during the movement.

[0036] In a specific implementation, as a preferred embodiment of the present invention, the STM32F407 main control chip controls the relay control module through the GPIO port, thereby driving the reversing valve to switch between the adsorption state and the vacuum breaking state, so that the robot walks in a three-three gait, that is, at any time at least three legs are in the support phase and generate adsorption force.

[0037] In a specific implementation, as a preferred embodiment of the present invention, the first servo motor 10, the second servo motor 13, and the third servo motor 15 are all serial bus servos and are uniformly controlled by the STM32F407 main control chip.

[0038] In a specific implementation, as a preferred embodiment of the present invention, the inertial measurement unit (IMU) is fixed in the center area of ​​the upper mounting plane of the upper fuselage 1. It is used to collect the three-axis attitude angle and acceleration data of the fuselage in real time and feed them back to the STM32F407 main control chip. The attitude adjustment task dynamically adjusts the angle of each joint servo according to the feedback data to maintain the fuselage level and conform to the blade surface.

[0039] The present invention also provides a control method based on the above-mentioned hexapod adhesive robot, comprising: S1. Motion commands are generated through a host computer or autonomous path planning and transmitted to the STM32F407 main control chip. In this embodiment, the single-board computer mounted on the robot performs global path planning based on the detection requirements of the wind turbine blades, generates a sequence of detection task commands, and sends the commands to the STM32F407 main control chip through a serial communication interface. The S2 and STM32F407 main control chips, based on the FreeRTOS multi-tasking system, schedule motion control tasks, calculate inverse kinematics solutions, and output control signals to the serial bus servos to achieve coordinated movement of each joint in a single leg. In this embodiment, after receiving instructions, the STM32F407 main control chip schedules the motion control task. This task, based on the 3x3 gait algorithm, performs inverse kinematics solving, generates coordinated motion trajectory instructions for 18 servos, and sends them to each servo for execution via the serial bus.

[0040] S3. Synchronous scheduling of the adsorption control task: Based on the gait phase, the relay is controlled to open and close via the GPIO port, thereby controlling the directional valve to operate, realizing vacuum breaking in the swing phase and vacuum pumping in the support phase. In this embodiment, when the mechanical leg is in the support phase, the motion control task synchronously triggers the adsorption control task via a signal. The adsorption control task outputs a high level through the GPIO port of the STM32F407 main control chip, driving the corresponding relay to close, thereby controlling the directional valve to the adsorption state, so that the corresponding three vacuum suction cups generate negative pressure, firmly adsorbing onto the blade surface, providing stable support for the robot. S4. Synchronous scheduling of attitude adjustment tasks: The inertial measurement unit (IMU) monitors the body attitude in real time and feeds it back to the STM32F407 main control chip to adjust the movement of each joint to maintain overall balance and adapt to the slope. In this embodiment, when the mechanical leg enters the swing phase and is about to lift, the adsorption control task outputs a low level through the GPIO port to control the reversing valve to switch to the vacuum breaking state, so that the suction cups can release the adsorption. At this time, the passive attitude adjustment mechanism composed of the spring 18 at the end of the lower leg and the fisheye bearing 23 begins to work, buffering the contact force and adaptively adjusting the attitude of the suction cups to prepare for the next landing adsorption. S5. Throughout the entire motion process, the inertial measurement unit (IMU) continuously feeds back the three-axis attitude angles and acceleration data of the robot body to the STM32F407 main control chip via the internal bus. Based on this feedback information, the attitude adjustment task fine-tunes the motion angles of each servo motor to compensate for changes in the blade surface or external interference, ensuring the stability of the robot body's attitude. S6. Repeat steps S2-S5 to achieve stable crawling, turning, and inspection operations on the wind turbine blade surface. In this embodiment, steps S2-S5 are repeated to drive the robot to move forward, turn, or overcome obstacles in a 3x3 gait until the entire planned inspection path is completed. The inspection module synchronously acquires images of the blade surface and transmits them back via the communication link, ultimately achieving autonomous, efficient, and stable inspection of the wind turbine blade.

[0041] In a specific implementation, as a preferred embodiment of the present invention, the FreeRTOS multitasking system divides functions into independent tasks and completes scheduling through a task scheduler. The tasks include: straight-line movement tasks, turning movement tasks, attitude adjustment tasks, hill climbing and adsorption tasks, and information transmission tasks. Synchronization and data sharing between tasks are achieved through message queues and semaphores.

[0042] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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 or all of the technical features therein. Such 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 the present invention.

Claims

1. A hexapod adsorption robot for inspecting offshore wind turbine blades, characterized in that, include: The double-layer fuselage structure and the six identical biomimetic single-leg structure (3) are as follows: The double-layer fuselage structure includes an upper fuselage (1) and a lower fuselage (6). The upper mounting plane of the upper fuselage (1) is equipped with a motion control system (4), and the lower mounting plane of the lower fuselage (6) is equipped with a vacuum adsorption system (7); wherein: The motion control system (4) includes an STM32F407 main control chip, a serial bus servo drive module, an inertial measurement unit (IMU), a relay control module, and a host computer communication interface. The STM32F407 main control chip performs multi-task scheduling of motion control tasks, adsorption control tasks, attitude adjustment tasks, and information transmission tasks through the FreeRTOS multi-task system to achieve stable crawling, turning, and detection operations of the robot on the surface of the variable curvature blade. The vacuum adsorption system (7) includes a vacuum pump, a reversing valve, an air pipe connector (19), a connector (20), a vacuum suction cup (21), a pressure sensor, and connecting pipes. The vacuum pump is connected to the air inlet of the reversing valve through the air pipe connector (19) and the connector (20). The working port of the reversing valve is connected to the vacuum suction cup (21) through a pipe. The pressure sensor is connected in series between the reversing valve and the vacuum suction cup (21) to detect the negative pressure value in real time and feed it back to the STM32F407 main control chip. The vacuum suction cup (21) is connected to the lower part (24) of the lower leg through a fisheye bearing (23), so that the suction cup (21) has a passive rotational degree of freedom. The six identical bionic single-leg structures (3) are each composed of a thigh (12), a middle leg (14), and a lower leg (16) connected in series. The thigh (12) is hinged to the upper fuselage (1) through the first servo motor (10) and the servo disk (11) to form a hip joint. The middle leg (14) is hinged to the thigh (12) through the second servo motor (13) to form a knee joint. The lower leg (16) is hinged to the middle leg (14) through the third servo motor (15) to form an ankle joint.

2. The hexapod adsorption robot according to claim 1, characterized in that, The upper fuselage (1) and the lower fuselage (6) are fixedly connected as an integral frame by the front end cover (2), the front support plate (5), the side support plate (8) and the rear end cover (9), wherein: The lower end of the front support plate (5) is threaded to the front end of the lower body (6), and the left and right sides are threaded to the front ends of the left and right support plates (8) respectively, forming a three-dimensional triangular reinforcement structure at the front of the frame. The upper edge of the side support plate (8) is threaded to the side beam of the upper fuselage (1), and the lower edge is threaded to the side beam of the lower fuselage (6), extending along the entire length of the fuselage to form continuous load-bearing beams on the left and right sides. The rear end cover (9) is threadedly connected to the rear end of the upper body (1), the rear end of the lower body (6), and the rear end of the two side support plates (8) to form a closed cavity at the tail of the robot. The front cover (2), front support plate (5), side support plate (8) and rear cover (9) together form a complete fuselage protection structure.

3. The hexapod adsorption robot according to claim 1, characterized in that, The lower leg (16) is composed of an upper part (25) and a lower part (24). The upper part (25) and the lower part (24) are flexibly connected by a spring (18) and locked with an upper fastening nut (17). The end of the lower part (24) is connected to the vacuum suction cup (21) in sequence via a connector (20), a suction cup connector (22) and a fisheye bearing (23) to form a passive attitude adjustment mechanism to adapt to the blade surface.

4. The hexapod adsorption robot according to claim 1, characterized in that, The vacuum adsorption system (7) adopts an independent control loop, including a vacuum pump, two pressure sensors and two reversing valves, which control three vacuum suction cups (21) respectively. When the robot is working, one group of suction cups maintains the adsorption state, and the other group of suction cups is in the vacuum breaking state, which is coordinated with the robot's three-three gait to ensure that there are always three suction cups reliably adsorbing during the movement.

5. The hexapod adsorption robot according to claim 1, characterized in that, The STM32F407 main control chip controls the relay control module through the GPIO port, which in turn drives the reversing valve to switch between the adsorption state and the vacuum breaking state, so that the robot walks in a three-legged gait, that is, at any time at least three legs are in the support phase and generate adsorption force.

6. The hexapod adsorption robot according to claim 1, characterized in that, The first servo (10), the second servo (13) and the third servo (15) are all serial bus servos and are controlled by the STM32F407 main control chip.

7. The hexapod adsorption robot according to claim 1, characterized in that, The inertial measurement unit (IMU) is fixed in the center area of ​​the upper mounting plane of the upper fuselage (1). It is used to collect the three-axis attitude angle and acceleration data of the fuselage in real time and feed them back to the STM32F407 main control chip. The attitude adjustment task dynamically adjusts the angle of each joint servo according to the feedback data to maintain the fuselage level and fit the blade surface.

8. A control method for a hexapod adsorption robot based on any one of claims 1-7, characterized in that, include: S1. Motion commands are generated through a host computer or autonomous path planning and transmitted to the STM32F407 main control chip; The S2 and STM32F407 main control chips are based on the FreeRTOS multi-task system to schedule motion control tasks, calculate inverse kinematics solutions, and output control signals to the serial bus servo motor to realize coordinated movement of each joint of a single leg. S3. Synchronously schedule the adsorption control task. According to the gait phase, control the on and off of the relay through the GPIO port, and then control the operation of the directional valve to realize the vacuum breaking of the swing phase and the vacuum pumping of the support phase. S4. Synchronous scheduling of attitude adjustment tasks: The inertial measurement unit (IMU) monitors the body attitude in real time and feeds it back to the STM32F407 main control chip to adjust the movement of each joint to maintain overall balance and adapt to the slope. S5. Throughout the entire motion process, the inertial measurement unit (IMU) continuously feeds back the three-axis attitude angles and acceleration data of the robot body to the STM32F407 main control chip via the internal bus. Based on this feedback information, the attitude adjustment task fine-tunes the motion angles of each servo motor to compensate for changes in the blade surface or external interference, ensuring the stability of the robot body's attitude. S6. Repeat steps S2-S5 to achieve stable crawling, turning and inspection operations of the robot on the surface of the wind turbine blade.

9. The control method according to claim 8, characterized in that, The FreeRTOS multitasking system divides functions into independent tasks, which are scheduled by a task scheduler. The tasks include: straight-line movement tasks, turning movement tasks, attitude adjustment tasks, hill climbing and adsorption tasks, and information transmission tasks. Synchronization and data sharing between tasks are achieved through message queues and semaphores.

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