Nondestructive testing robot for foundation pit reinforced concrete structure

Abstract

The invention discloses a nondestructive testing robot for a foundation pit steel-concrete structure, and belongs to the technical field of testing robots, the nondestructive testing robot comprises a robot body, a through mounting groove is formed in the center of the robot body, an adsorption turbine is arranged in the mounting groove, a mechanical arm is arranged on the upper surface of the robot body, and a testing assembly is arranged at the output end of the mechanical arm; driving mechanisms are arranged on the two sides of the robot body, and course monitoring assemblies are arranged in the driving mechanisms. A robot body is adsorbed and stabilized through a turbine, a path is cleaned through a passive mud scraping plate in the moving process, yawing in the walking process is avoided through a course monitoring assembly, during detection, a detection assembly is pressed through a mechanical arm, an execution sliding block is pushed out through an action push cylinder, the surface is cleaned through an active mud scraping plate firstly, and then a coupling agent is accurately added through an injection pipe; and finally, an ultrasonic flaw detector for buffering by using a disc spring and an inclined plane is in contact with the coupling layer for detection under stable pressure.

Description

Technical Field

[0001] This invention relates to the field of inspection robot technology, and in particular to a non-destructive testing robot for a steel-concrete structure foundation pit. Background Technology

[0002] In foundation pit engineering, reinforced concrete structures may suffer damage such as cracks, voids, steel corrosion, or insufficient protective layer thickness during construction and service due to stress changes, material defects, or construction quality issues. To ensure the overall safety of the structure, it is necessary to identify and assess these damages in a timely manner through non-destructive testing. However, in the ultra-deep foundation pits of subways (such as the Beijing Yongdingmenwai Station project) that adopt underwater excavation and underwater concrete sealing construction, the working environment is extremely harsh: the design water level is as deep as 19 meters, and the foundation pit is filled with highly turbid mud water.

[0003] In this environment, the turbid muddy water results in extremely low visibility, and the visual navigation module of the existing inspection robot completely fails, making it unable to correct itself once it deviates from its course.

[0004] Meanwhile, the core of ultrasonic testing in existing testing robots lies in the effective acoustic coupling between the probe and the structural surface (ensuring the transmission of sound energy). However, the surface of the underwater structure to be inspected is generally covered by a thick layer of mud. The coupling agent cannot form an effective medium between the probe, the structural surface and the mud layer. The sound wave is severely attenuated and distorted when it penetrates the mud layer, resulting in weak echo signals or even no reception.

[0005] In summary, existing non-destructive testing robots are limited by harsh muddy and water environments, making reliable navigation and effective ultrasonic testing impossible. Therefore, a non-destructive testing robot for reinforced concrete structures in foundation pits is proposed to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to solve the problem that existing inspection robots cannot achieve reliable navigation and effective ultrasonic inspection in harsh muddy and watery environments, and to propose a non-destructive inspection robot for steel-concrete structures in foundation pits.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A non-destructive testing robot for reinforced concrete structures in foundation pits includes a robot body with a flat bottom surface and a control unit inside. A through mounting groove is formed at the center of the robot body, and an adsorption turbine is installed within the mounting groove. A robotic arm and multiple longitudinal hanging rings for horizontal suspension of the robot body are located on the upper surface of the robot body. A detection component is installed at the output end of the robotic arm. A coupling agent storage chamber is located inside the robot body near the robotic arm, and a gear pump for pumping coupling agent is installed within the coupling agent storage chamber. The gear pump is connected to the coupling agent storage chamber. Drive mechanisms are located on both sides of the robot body.

[0009] The detection assembly includes a mounting frame and a sliding sleeve. The upper surface of the mounting frame is fixedly connected to the end effector of the robotic arm. The sliding sleeve contains an execution slider, which contains an ultrasonic flaw detector for non-destructive testing and an injection tube for adding coupling agent.

[0010] The drive mechanism includes two drive cabins arranged symmetrically about the robot body axis. Both drive cabins are fixedly connected to the robot body. The bottom of each drive cabin is provided with a passive mud scraper, a track, and a heading monitoring component in sequence from the direction of travel. A transverse hanging ring is fixedly connected to the end of the drive cabin away from the robotic arm for suspending the robot body in a vertical position.

[0011] Preferably, the output direction of the adsorption turbine is vertically downward. By using the adsorption turbine in conjunction with the flat bottom surface of the robot body, the robot body is adsorbed onto the target surface using Bernoulli's principle.

[0012] Preferably, the end and bottom of the sliding sleeve away from the drive compartment are open, and two limiting grooves are formed inside the sliding sleeve near the drive compartment. An installation groove is formed between the limiting grooves, and an actuating push cylinder is installed in the installation groove. The output end of the actuating push cylinder is fixedly connected to the actuating slider.

[0013] Preferably, one side of the actuator slider is provided with a slide rod, which is slidably connected to the limiting slide groove. The other side of the actuator slider is provided with an active mud scraper. The length of the active mud scraper is greater than the length of the actuator slider and matches the open part at the bottom of the slide sleeve. An action groove is opened inside the actuator slider, and a buffer frame is slidably connected inside the action groove.

[0014] Preferably, the buffer frame is fixedly connected to the ultrasonic flaw detector, the top of the buffer frame is provided with a disc spring for providing a reset force, and the bottom of the buffer frame is set as an inclined surface so that it can extend and retract smoothly during operation.

[0015] Preferably, the injection tube is installed inside the actuator slider and is located between the active scraper and the buffer frame. It can perform the action before the buffer frame when performing the detection. The output end of the injection tube is equipped with a solenoid valve, and the input end of the injection tube is fixedly connected to a coupling agent delivery tube. The coupling agent delivery tube passes through the actuator slider and the sliding sleeve in sequence and is connected to the gear pump.

[0016] Preferably, the passive scraper is slidably installed inside the drive compartment and its bottom end extends through the drive compartment. Above the passive scraper is a compression spring for providing clamping force and restoring elasticity, so that it can fit tightly against the working surface.

[0017] Preferably, the heading monitoring component includes a heading measuring wheel fixed by a bracket, the heading measuring wheel being connected to an encoder through the bracket, the encoder being electrically connected to a control unit in the robot body, and being able to determine whether there is yaw by the speed difference of the heading measuring wheel.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. This invention sets up a passive mud scraper and a heading monitoring component. The passive mud scraper continuously removes mud obstacles in front of the tracks, and the encoder detects the wheel speed difference between the two heading measuring wheels in real time and feeds it back to the control unit. The control unit dynamically adjusts the speed difference between the two tracks accordingly, so as to achieve precise walking and yaw correction of the robot along a predetermined straight path in a low visibility muddy environment.

[0020] 2. This invention, through the setting of a detection component, achieves a step-by-step coordinated action by first pushing out mud and water and scraping away foreign objects with an active mud scraper, then injecting coupling agent with an injection tube, and finally using a buffer frame and disc spring to gently press and compress the ultrasonic flaw detector. This enables the creation of a flat and clean area in a muddy environment, the formation of a sound wave transmission medium, and ensures stable and reliable contact between the probe and the surface to be tested, thus guaranteeing the stability and reliability of the ultrasonic detection signal.

[0021] 3. This invention achieves the function of climbing, moving and non-destructive testing in harsh environments such as low visibility in water-bearing foundation pits through the synergistic effect of the adsorption turbine, drive mechanism, heading monitoring component and detection component. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of a non-destructive testing robot for a steel-concrete structure foundation pit proposed in this invention.

[0023] Figure 2 This is an overall structural assembly drawing of a non-destructive testing robot for a steel-concrete structure foundation pit proposed in this invention;

[0024] Figure 3This is a structural cross-sectional view of the drive mechanism in a non-destructive testing robot for a steel-concrete foundation pit, as proposed in this invention.

[0025] Figure 4 This is a cross-sectional view of the internal structure of the robot body in the non-destructive testing robot for a steel-concrete structure foundation pit proposed in this invention.

[0026] Figure 5 This is a structural assembly diagram of the detection component in a non-destructive testing robot for a steel-concrete foundation pit, as proposed in this invention.

[0027] Figure 6 This is a cross-sectional view of the detection component in the detection state of a non-destructive testing robot for a steel-concrete foundation pit proposed in this invention.

[0028] Figure 7 This is a cross-sectional view of the detection component in the standby state of a non-destructive testing robot for a steel-concrete foundation pit proposed in this invention.

[0029] Figure 8 This is a cross-sectional view of the internal structure of the execution slider in a non-destructive testing robot for a steel-concrete structure foundation pit, as proposed in this invention.

[0030] Figure 9 This is an assembly diagram of the ultrasonic flaw detector, comprising the execution slider, buffer frame, and other components, in a non-destructive testing robot for a reinforced concrete foundation pit structure proposed in this invention.

[0031] Figure 10 This is a cross-sectional view of the heading measurement wheel in a non-destructive testing robot for a steel-concrete structure foundation pit proposed in this invention.

[0032] In the diagram: 1. Robot body; 2. Adsorption turbine; 3. Robotic arm; 4. Coupling agent storage tank; 5. Gear pump; 6. Mounting frame; 7. Sliding sleeve; 8. Actuating slider; 9. Ultrasonic flaw detector; 10. Injection tube; 11. Drive compartment; 12. Passive scraper; 13. Track; 14. Sliding rod; 15. Active scraper; 16. Buffer frame; 17. Disc spring; 18. Solenoid valve; 19. Coupling agent delivery tube; 20. Compression spring; 21. Heading measuring wheel; 22. Encoder. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Example, refer to Figures 1 to 10 A non-destructive testing robot for steel-concrete structures in foundation pits includes a robot body 1 with a flat bottom surface. The robot body 1 has a control unit inside for coordinating the movement of the drive mechanism, receiving signals from the encoder 22, and controlling the testing process. A through mounting slot is opened in the center of the robot body 1, and an adsorption turbine 2 is installed in the mounting slot. A robotic arm 3 and multiple longitudinal hanging rings for horizontal suspension of the robot body 1 are provided on the upper surface of the robot body 1. The robotic arm 3 is used to manipulate the testing component to contact the surface to be tested. The output end of the robotic arm 3 is equipped with the testing component. A coupling agent storage chamber 4 is provided inside the robot body 1 on the side near the robotic arm 3. A gear pump 5 for pumping coupling agent is provided in the coupling agent storage chamber 4. The gear pump 5 is connected to the coupling agent storage chamber 4. Drive mechanisms are provided on both sides of the robot body 1.

[0037] The detection assembly includes a mounting frame 6 and a sliding sleeve 7. The upper surface of the mounting frame 6 is fixedly connected to the end effector of the robotic arm 3. The sliding sleeve 7 is provided with an execution slider 8. The execution slider 8 is provided with an ultrasonic flaw detector 9 for non-destructive testing and an injection tube 10 for adding coupling agent.

[0038] The drive mechanism includes two drive cabins 11 arranged symmetrically about the axis of the robot body 1. Both drive cabins 11 are fixedly connected to the robot body 1. The bottom of the drive cabin 11 is provided with a passive mud scraper 12, a track 13 and a heading monitoring component in sequence from the direction of travel. A transverse hanging ring is fixedly connected to the end of the drive cabin 11 away from the robotic arm 3 for suspending the robot body 1 in a vertical state.

[0039] It should be noted that the robotic arm 3, ultrasonic flaw detector 9, gear pump 5, and track 13 are all existing technologies.

[0040] Furthermore, the output direction of the adsorption turbine 2 is vertically downward. Through the combined use of the adsorption turbine 2 and the flat bottom surface of the robot body 1, the robot body 1 is adsorbed to the target surface using the Bernoulli principle. This is used to stabilize the robot body 1 during the detection process, counteract the reaction force of gravity or the operation of the robotic arm 3, and ensure that the detection component maintains stable contact with the surface to be tested.

[0041] Furthermore, the end and bottom of the sliding sleeve 7 away from the drive compartment 11 are open. Two limiting slide grooves are opened inside the sliding sleeve 7 near the drive compartment 11. An installation groove is opened between the limiting slide grooves. An actuating push cylinder is installed in the installation groove. The output end of the actuating push cylinder is fixedly connected to the execution slider 8 and is used to drive the execution slider 8 to reciprocate linearly along the limiting slide groove inside the sliding sleeve 7 to realize the extension and reset of the detection component.

[0042] Furthermore, a sliding rod 14 is provided on one side of the actuator slider 8, and the sliding rod 14 is slidably connected to the limiting sliding groove. An active scraper 15 is provided on the other side of the actuator slider 8. The length of the active scraper 15 is greater than the length of the actuator slider 8 and matches the open part at the bottom of the sliding sleeve 7. An action groove is opened inside the actuator slider 8, and a buffer frame 16 is slidably connected inside the action groove for installing and buffering the ultrasonic flaw detector 9.

[0043] The further advantage of the above is that when the slider 8 extends, the active scraper 15 contacts the surface to be tested before the injection tube 10 and the ultrasonic flaw detector 9, pushes out the mud and water in that area, and scrapes away foreign objects (such as mud in an attached state) that may affect the ultrasonic coupling on the surface to be tested in that area.

[0044] Furthermore, the buffer frame 16 is fixedly connected to the ultrasonic flaw detector 9. The top of the buffer frame 16 is provided with a disc spring 17 for providing a reset force, and the bottom of the buffer frame 16 is set as an inclined surface so that it can extend and retract smoothly during operation. Through the disc spring 17 and the inclined surface at the bottom of the buffer frame 16, the ultrasonic flaw detector 9 is buffered when it contacts the surface to be tested, ensuring that the probe is in close contact with the surface under a certain pressure, while avoiding rigid impact that could damage the probe and affect the coupling effect, thereby improving the stability and reliability of the detection signal.

[0045] Furthermore, the injection tube 10 is installed inside the actuator slider 8. The injection tube 10 is located between the active scraper 15 and the buffer frame 16, and can perform the action before the buffer frame 16 during the test. The output end of the injection tube 10 is equipped with a solenoid valve 18, which is used to control the timing and flow rate of the coupling agent injection. The input end of the injection tube 10 is fixedly connected to the coupling agent delivery tube 19. The coupling agent delivery tube 19 passes through the actuator slider 8 and the sliding sleeve 7 in sequence and is connected to the gear pump 5. After the active scraper 15 cleans and before the ultrasonic flaw detector 9 contacts, the injection tube 10 can accurately inject the coupling agent onto the cleaned surface of the test area to form a good sound wave transmission medium.

[0046] Furthermore, the passive scraper 12 is slidably installed inside the drive compartment 11 and its bottom end penetrates through the drive compartment 11. Above the passive scraper 12 is a compression spring 20 for providing clamping force and reset spring force, so that it can be in close contact with the working surface. During the movement of the robot, it can continuously scrape away mud and other obstacles on the path to be measured in front of the track 13, providing a relatively clean working environment for the subsequent heading monitoring components and preventing the heading measurement wheel 21 from slipping due to the attached mud and affecting the heading judgment.

[0047] Furthermore, the heading monitoring component includes a heading measuring wheel 21 fixed by a bracket. The heading measuring wheel 21 is connected to an encoder 22 through the bracket. The encoder 22 is electrically connected to the control unit in the robot body 1 and can determine whether there is yaw by the speed difference of the heading measuring wheel 21.

[0048] The further advantage of the above is that the heading measurement wheel 21 is in close contact with the surface to be measured and rolls as the robot moves, providing the encoder 22 to monitor the rotation speed of the heading measurement wheels 21 on both sides in real time. When there is a difference in the rotation speed on both sides, the control unit determines that the robot has yawed and can correct the heading by adjusting the speed difference of the tracks 13 on both sides, so as to ensure that the robot walks along the predetermined straight path, thereby maintaining accurate heading in mud and water with extremely low visibility.

[0049] When this invention is in use, the robot body 1 is suspended horizontally to the bottom of the pit by a hoisting device through the longitudinal hanging ring on the upper surface of the robot body 1, or it is suspended vertically near the vertical support piles and the side wall of the diaphragm wall through the transverse hanging ring at one end of the drive cabin 11. When the robot body 1 is close to the horizontal bottom surface or the vertical wall surface, the adsorption turbine 2 is activated. The adsorption turbine 2 sprays water vertically downward at high speed. According to Bernoulli's principle, the high-speed water flow forms a low-pressure zone between the flat bottom surface of the robot body 1 and the target surface, generating an adsorption force, which firmly adsorbs the robot body 1 onto the target surface, providing a stable platform for detection.

[0050] During travel, the robot body 1 is driven forward by the rotation of the track 13. During travel, the passive scraper 12 located in front of the track 13 is pressed against the working surface by the continuous clamping force of the compression spring 20. As the robot moves, the passive scraper 12 continuously scrapes away mud and other obstacles on the path to be measured in front of the track 13, improving the grip of the track 13. At the same time, the heading measuring wheel 21 is pressed against the surface that has been initially cleaned by the scraper and rolls with the robot. The speed signal is transmitted to the control unit in the drive compartment 11 in real time through the encoder 22. The control unit continuously compares the speed of the heading measuring wheels 21 on both sides of the robot. When there is a difference in the speed on both sides, it indicates that the robot has yawed. At this time, the control unit immediately issues an instruction to adjust the speed difference of the two tracks 13, speeding up the speed of the lagging track 13 and slowing down the speed of the leading track 13, thereby correcting the heading and ensuring that the robot travels strictly along the predetermined straight path.

[0051] During testing, the control unit controls the robotic arm 3 to perform an action, pressing the sliding sleeve 7 down and tightly adhering it to the surface of the point to be tested. Then, the control unit controls the action to extend the push cylinder, pushing the actuator slider 8 to move linearly along the limiting groove in the sliding sleeve 7 towards the surface to be tested and extend it. When the actuator slider 8 extends, the active scraper 15 first contacts the surface to be tested, and pushes out the mud and water at the opening of the sliding sleeve 7 through the active scraper 15. At the same time, it scrapes away the mud and other foreign objects that affect ultrasonic coupling, such as mud, which are attached to the area, and cleans a relatively clean and flat area that is free of mud and water.

[0052] When the slider 8 extends to expose the injection tube 10, the control unit opens the solenoid valve 18 and the gear pump 5. The gear pump 5 pumps out the coupling agent from the coupling agent storage chamber 4 and delivers it to the injection tube 10 through the coupling agent delivery tube 19. Under the control of the solenoid valve 18, the injection tube 10 injects an appropriate amount of coupling agent onto the surface of the area to be tested, which has been cleaned by the active scraper 15, forming a uniform acoustic wave transmission medium, creating the necessary conditions for ultrasonic flaw detection.

[0053] After the coupling agent is applied by the injection tube 10, the action cylinder continues to push the execution slider 8 to extend, causing the buffer frame 16 to contact the surface to be tested coated with coupling agent. As the bottom of the buffer frame 16 leaves the sealing point of the sliding sleeve 7, it extends smoothly through the contact between its bottom inclined surface and the inner wall of the bottom of the sliding sleeve 7 and the elastic force of the disc spring 17, avoiding rigid impact damage to the probe. After extension, the elastic force of the disc spring 17 ensures that the ultrasonic flaw detector 9 probe is in close contact with the surface to be tested under a certain pressure, ensuring good and stable contact between the probe and the coupling agent and the surface, so that a stable and reliable ultrasonic signal can be obtained during testing. When collecting data, the ultrasonic flaw detector 9 emits ultrasonic pulses into the interior of the reinforced concrete structure and receives the reflected echo. The echo signal is converted into an electrical signal and transmitted back to the control unit for processing and analysis to detect defects inside the concrete and parameters such as the position of the reinforcing bars and the thickness of the protective layer.

[0054] After the test is completed, the actuator retracts, pulling the actuator slider 8, along with the buffer frame 16, ultrasonic flaw detector 9, injection tube 10, and active scraper 15, back into the sliding sleeve 7 along the limiting slide groove. At this time, the disc spring 17 installed on the top of the buffer frame 16 is compressed, providing a reset elastic force for the buffer frame 16 to extend again, completing the reset of the detection component. After the detection component is reset, the robotic arm 3 drives the sliding sleeve 7 to lift away from the surface where the test was completed. Finally, the robot body 1 moves to a new area to perform the test again.

[0055] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A non-destructive testing robot for reinforced concrete structures in foundation pits, comprising a robot body (1), characterized in that, The robot body (1) has a flat bottom surface. The robot body (1) has a control unit inside. The robot body (1) has a through mounting groove in the center. The mounting groove has an adsorption turbine (2). The upper surface of the robot body (1) has a mechanical arm (3) and multiple longitudinal hanging rings for horizontal suspension of the robot body (1). The output end of the mechanical arm (3) has a detection component. The robot body (1) has a coupling agent storage chamber (4) and a gear pump (5) for pumping coupling agent inside the side near the mechanical arm (3). The gear pump (5) is connected to the coupling agent storage chamber (4). The robot body (1) has a drive mechanism on both sides. The detection assembly includes a mounting frame (6) and a sliding sleeve (7). The upper surface of the mounting frame (6) is fixedly connected to the end effector of the robotic arm (3). The sliding sleeve (7) is provided with an execution slider (8). The execution slider (8) is provided with an ultrasonic flaw detector (9) for non-destructive testing and an injection tube (10) for adding coupling agent. The drive mechanism includes two drive cabins (11) arranged symmetrically with respect to the axis of the robot body (1). Both drive cabins (11) are fixedly connected to the robot body (1). The bottom of the drive cabin (11) is provided with a passive mud scraper (12), a track (13) and a heading monitoring component in sequence from the driving direction. A transverse hanging ring is fixedly connected to the end of the drive cabin (11) away from the robotic arm (3) for suspending the robot body (1) in a vertical state.

2. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 1, characterized in that, The output direction of the adsorption turbine (2) is vertically downward. Through the combined use of the adsorption turbine (2) and the flat bottom surface of the robot body (1), the robot body (1) is adsorbed to the target surface by utilizing Bernoulli's principle.

3. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 1, characterized in that, The end and bottom of the sliding sleeve (7) away from the drive compartment (11) are open. Two limiting grooves are opened inside the sliding sleeve (7) near the drive compartment (11). An installation groove is opened between the limiting grooves. An action push cylinder is installed in the installation groove. The output end of the action push cylinder is fixedly connected to the execution slider (8).

4. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 3, characterized in that, The execution slider (8) has a slide rod (14) on one side, which is slidably connected to the limiting slide groove. The execution slider (8) has an active scraper (15) on the other side. The length of the active scraper (15) is greater than the length of the execution slider (8) and matches the open part at the bottom of the sliding sleeve (7). An action groove is opened inside the execution slider (8), and a buffer frame (16) is slidably connected inside the action groove.

5. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 4, characterized in that, The buffer frame (16) is fixedly connected to the ultrasonic flaw detector (9) inside. The top of the buffer frame (16) is provided with a disc spring (17) for providing a reset force. The bottom of the buffer frame (16) is set as an inclined surface so that it can extend and retract smoothly during operation.

6. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 1, characterized in that, The injection tube (10) is installed inside the actuator slider (8). The injection tube (10) is located between the active scraper (15) and the buffer frame (16). It can perform the action before the buffer frame (16) when performing the test. The output end of the injection tube (10) is equipped with a solenoid valve (18). The input end of the injection tube (10) is fixedly connected to a coupling agent delivery tube (19). The coupling agent delivery tube (19) passes through the actuator slider (8) and the sliding sleeve (7) in sequence and is connected to the gear pump (5).

7. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 1, characterized in that, The passive scraper (12) is slidably installed inside the drive compartment (11) and its bottom end penetrates through the drive compartment (11). Above the passive scraper (12) is a compression spring (20) for providing clamping force and restoring force, so that it can fit tightly against the working surface.

8. The non-destructive testing robot for reinforced concrete structures in foundation pits according to claim 1, characterized in that, The heading monitoring component includes a heading measuring wheel (21) fixed by a bracket. The heading measuring wheel (21) is connected to an encoder (22) through the bracket. The encoder (22) is electrically connected to the control unit in the robot body (1) and can determine whether there is a yaw by the speed difference of the heading measuring wheel (21).

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