Steel pipe arch deformation detection device and method

Abstract

The application discloses a kind of steel pipe arch deformation detection device and method, device includes walking track and detection robot, walking track is formed by being fixed in steel pipe arch by two pieces of L-shaped steel sheet, detection robot moves on track by driving roller, robot is composed of walking mechanism, void detection mechanism and deformation detection mechanism, walking mechanism includes annular disc, telescopic frame and driving roller, driving roller is contacted with track by second spring, void detection mechanism is identified by knock unit and analysis unit to identify the position of void point by collecting the sound of knocking the surface of steel pipe, deformation detection mechanism generates three-dimensional point cloud after collecting ground distance and trajectory data, and ideal curve is generated by adopting quadric surface fitting, the deviation of actual and ideal curve is calculated, finally, through deformation variable statistics and thermodynamic diagram visualization, the results of void and deformation are output, report is generated and alarm is triggered.The application can realize the accurate detection of steel pipe arch deformation and void, improve detection efficiency and safety.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of steel pipe concrete arch bridge detection, and particularly relates to a steel pipe arch deformation detection device and method. BACKGROUND

[0002] The steel pipe concrete arch bridge is a composite structure bridge combining steel and concrete, which fills the steel pipe with concrete, limits the expansion of the compressed concrete by radial constraint of the steel pipe, and makes the concrete in a three-way compression state, thereby significantly improving the compressive strength. The main feature of the steel pipe concrete arch bridge is the arch rib structure, which usually includes single-limb circular pipe, double-limb dumbbell-shaped section and four-limb arch rib structure and other forms. These structural forms can be selected according to the design requirements and span size of the bridge to meet different engineering needs. In terms of construction, the steel pipe concrete arch bridge has the advantages of light hoisting weight and simple construction. The steel pipe can be used as a rigid load-bearing framework to simplify the construction process and shorten the construction period. At the same time, due to the presence of the steel pipe, concrete pouring can be conveniently carried out, avoiding the complex formwork work in the construction of traditional concrete bridges.

[0003] The monitoring items of the steel pipe concrete arch bridge include void detection and deformation detection, among which the void detection can adopt ultrasonic wave and manual detection methods. The ultrasonic wave detection has accurate detection precision and can achieve non-damage detection, but the ultrasonic wave detection needs to smear coupling agent, and then install equipment on both sides of the steel pipe, so the detection operation is relatively complex, and the personnel operation detection in the air is more troublesome. The manual detection is to detect by knocking the surface of the steel pipe, and judge the void by listening to the knocking sound, which is very dependent on the experience of personnel. The deformation detection of the steel pipe arch bridge is a long-term process, and the deformation degree of the steel pipe arch rib needs to be detected every period of time, and the detection method is relatively troublesome. SUMMARY

[0004] The technical problem to be solved by the application is to provide a steel pipe arch deformation detection device and method which can realize accurate detection of steel pipe arch deformation and void, and improve detection efficiency and safety.

[0005] The technical scheme of the application is as follows:

[0006] The utility model provides a kind of steel pipe arch deformation detection device, comprising: walking track and detection robot, the walking track is arranged on the steel pipe arch of steel pipe, the walking track includes two pieces of L-shaped steel sheet, the steel sheet is fixedly connected with steel pipe arch, and the two pieces of steel sheet are connected with steel pipe arch to form walking track;The detection robot moves on walking track, and the detection robot includes walking mechanism, void detection mechanism and deformation detection mechanism, the walking mechanism moves on walking track, and the walking mechanism includes two rotating frames, the rotating frame includes annular disc and four telescopic frames, the four telescopic frames are distributed in the side of annular disc in pairs, and the four telescopic frames are combined to form X-shaped structure, one end of the telescopic frame is slidably connected with annular disc, the other end of the telescopic frame is provided with driving roller, the driving roller is in contact with the steel sheet of walking track, second spring is arranged between the two adjacent telescopic frames, connecting shaft is arranged between the two annular discs, the two annular discs are rotatably connected with connecting shaft, detection mechanism connecting device is arranged on the annular disc of walking mechanism towards the outside of steel pipe arch, the void detection mechanism and the deformation detection mechanism are fixedly connected on the detection mechanism connecting device, the detection mechanism connecting device includes fixed connection unit and movable connection unit, the fixed connection unit is connected with annular disc and void detection mechanism respectively, and the movable connection unit is connected with deformation detection mechanism, the movable connection unit includes hollow column and movable shaft rotating in hollow column, the hollow column is sleeved with fixed connection unit, the deformation detection mechanism is arranged at the bottom of movable shaft, and the deformation detection mechanism includes infrared range finder and path recorder, the void detection mechanism includes rack, knocking unit, recording unit and analysis unit, the rack is fixedly connected with fixed connection unit, first air cylinder is arranged in the rack, the telescopic end of first air cylinder is connected with knocking unit, the knocking unit includes knocking plate and knocking hammer, the bottom of knocking plate is fixedly connected with the telescopic end of first air cylinder, and a plurality of knocking hammers are fixedly connected with the top of knocking plate, and the recording unit and the analysis unit are arranged in the rack.

[0007] Further, the side of the annular disc is provided with a groove slide rail, one end of the telescopic frame is provided with a sliding sheet, and the sliding sheet slides on the groove slide rail.

[0008] Further, the fixed connection unit is a circular sleeve structure, one end of the fixed connection unit is sleeved with the hollow column, and the other end of the fixed connection unit is rotatably connected with the annular disc through a plurality of support rods, one end of the support rod is in contact with the inner wall of the fixed connection unit, and the other end of the support rod is fixedly connected with the disc surface of the annular disc.

[0009] Further, the recording unit includes microphone and low-noise amplifier, and the analysis unit is STM32 series microcontroller.

[0010] Further, the infrared distance meter is a ToF infrared distance meter, and the path recorder comprises an optical rotary encoder and an inertial measurement unit.

[0011] Further, a driving motor is arranged on the driving roller, and the driving motor is connected with the driving roller through a transmission gear.

[0012] A deformation detection method of a steel pipe arch deformation detection device, comprising the following steps:

[0013] Step 1, robot walking and path recording, comprising the following steps:

[0014] Step 1.1, placing the detection robot: placing the walking mechanism of the detection robot in the track composed of steel sheets, ensuring that the driving roller is tightly pressed against the inner wall of the steel sheet under the action of the second spring;

[0015] Step 1.2, starting the walking mechanism: starting the driving roller, and the detection robot starts moving along the walking track, and the path recorder records the walking trajectory data (x i ,y i ), and records a position point every fixed time interval Δt;

[0016] Step 2, starting the knocking unit and collecting sound data, comprising the following steps:

[0017] Step 2.1, starting the knocking unit: starting the first cylinder, and driving the knocking hammer to knock the surface of the steel pipe at a fixed frequency f c and a fixed force;

[0018] Step 2.2, recording sound by the sound recording unit: the sound recording unit records the knocking sound signal s(t);

[0019] Step 2.3, sound frequency analysis: the analysis unit performs Fourier transform on the knocking sound signal s(t) to obtain a frequency domain signal:

[0020]

[0021] Wherein, S(f) represents the amplitude in the frequency domain, which is used to identify the frequency characteristics of the knocking sound, s(t) represents the knocking sound signal, and f represents the frequency;

[0022] Analyzing the frequency characteristics, comparing the actual frequency peak f measured with the preset threshold f threshold :

[0023] If |f measured -f ideal |> f threshold , it is determined that there is a void at this point;

[0024] Recording the void point position P i= (x i , y i , z i ) ;

[0025] Step 3, infrared ranging and three-dimensional data fusion, including the following steps:

[0026] Step 3.1, collect ground distance: the infrared range finder synchronously records the ground distance z i of each walking point;

[0027] Step 3.2, generate three-dimensional point cloud: combine the walking trajectory data (x i , y i ) provided by the path recorder and the z i data provided by the infrared range finder to generate a three-dimensional point cloud:

[0028] P i = (x i , y i , z i ),

[0029] wherein P i represents a three-dimensional coordinate point of the detection robot at a certain position on the surface of the steel pipe arch;

[0030] Step 4, steel pipe arch curve fitting, including the following steps:

[0031] Step 4.1, fitting ideal curve: assuming that the ideal shape of the steel pipe arch is a quadratic surface, the model is:

[0032] z(z,y) = a0 + a1x + a2y + a3x 2 + a4y 2 + a5xy,

[0033] wherein z(x, y) represents the fitted ideal steel pipe arch height, x and y represent the horizontal coordinate and vertical coordinate provided by the path recorder respectively, a0, a1, a2, a3, a4, a5 represent fitting coefficients, which are solved by least squares method;

[0034] Step 4.2, fitting parameter solving: minimize the error function by least squares method: that is:

[0035]

[0036] wherein J represents the error function, (x i , y i , z i ) represents the data points collected by the path recorder and the infrared range finder, and n represents the sample number;

[0037] The optimal fitting coefficients a0, a1, a2, a3, a4, a5 are obtained by minimizing the error function J, and then the curved surface formula of the ideal steel tube arch is obtained.

[0038] Step 5, steel tube arch deformation calculation, including the following steps:

[0039] Step 5.1, deformation calculation: for each point P i , calculate the deviation between the actual value and the ideal fitting value: Δz i =z i -z(x i ,y i ),

[0040] Wherein, z i represents the actual measurement value of the infrared range finder, z(x i , y i ) represents the ideal fitting value, Δz i represents the deformation of point i;

[0041] Step 5.2, statistical deformation data, including the maximum deformation and the average deformation, the expression of the maximum deformation is:

[0042]

[0043] Wherein, Δz max represents the maximum deformation, Δz i represents the deformation of point i;

[0044] The expression of the average deformation is:

[0045]

[0046] Wherein, Δz mean represents the average deformation, Δz i represents the deformation of point i, and n represents the sample number;

[0047] Step 6, analysis of void and deformation combination, including the following steps:

[0048] Step 6.1, void point marking: mark all void points (x i , y i , z i ), and separately count the deformation of the void position;

[0049] Step 6.2, deformation thermodynamic diagram: generate the deformation thermodynamic diagram of the steel tube arch according to the distribution of the deformation Δz i , and mark the void points and the maximum deformation area;

[0050] Step 7, system output, including the following steps:

[0051] Step 7.1, report generation: output the hollow point and its specific location information (x i , y i , z i ), output the deformation data including the maximum deformation and the average deformation;

[0052] Step 7.2, visualization: use three-dimensional visualization tools Matlab or ROS or OpenGL to generate three-dimensional morphological map of steel pipe arch, display deformation thermal map and mark out hollow point and maximum deformation area;

[0053] Step 7.3, feedback report: set threshold according to deformation, trigger alarm mechanism and prompt operator to handle in time.

[0054] The beneficial effects of the present application are:

[0055] 1. High-precision detection: the present application can accurately identify the hollow point on the surface of the steel pipe arch and its specific location by combining the knocking unit, the recording unit and the analysis unit with Fourier transform; three-dimensional point cloud is generated by combining the infrared distance meter and the path recorder, and high-precision calculation of the deformation of the steel pipe arch is realized by using the quadric surface fitting model and the least square method;

[0056] 2. High efficiency: the detection robot of the present application can automatically travel along the walking track without manual intervention, improving the detection efficiency; the knocking sound is processed in real time by the recording unit and the analysis unit, and the hollow is quickly judged, and the real-time path and deformation data recording are realized by combining the path recorder;

[0057] 3. Visual analysis: the present application constructs the actual morphology of the steel pipe arch through three-dimensional point cloud, and provides intuitive visual images of deformation distribution by combining ideal surface fitting; the deformation distribution is displayed in the form of thermal map, and the hollow point and the maximum deformation area are clearly marked, which facilitates users to understand and locate the problem;

[0058] 4. Multifunctional detection: the present application can comprehensively evaluate the structural integrity of the steel pipe arch by combining the hollow and deformation detection of the steel pipe arch; the hollow point position, deformation variable statistics (maximum value, average value) and three-dimensional morphology report are output, which provides reliable basis for subsequent maintenance;

[0059] 5. Reliability and adaptability: the walking mechanism of the present application is designed ingeniously, the tight contact of the driving roller and the track is ensured by the second spring, which adapts to different curvatures and environments of the steel pipe arch; by using ToF infrared distance meter and optical rotary encoder, it has strong anti-environmental interference ability and can still maintain high precision in complex working conditions;

[0060] 6. Safety: The application sets threshold values according to the deformation amount and the void condition, triggers an alarm to prompt the operator to handle it in time, avoids structural safety hazards, and reduces the safety risks of manual intervention through robot operations such as knocking and distance measurement.

[0061] 7. Strong practicability: The void detection mechanism and the deformation detection mechanism of the application can be independently installed and can be flexibly adjusted or upgraded according to actual needs; the overall design of the detection device can adapt to steel pipe arches of different sizes and shapes, and has wide engineering application value.

[0062] In summary, the steel pipe arch deformation detection device and method of the application have the advantages of high precision, high efficiency and reliability, provide an efficient and comprehensive solution for structural health monitoring of steel pipe arches, and have good engineering promotion value. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 is a structural schematic diagram of a detection robot of a steel pipe arch deformation detection device of the application.

[0064] Figure 2 is a structural schematic diagram of an extension frame of a steel pipe arch deformation detection device of the application.

[0065] Figure 3 is a structural schematic diagram of a void detection mechanism of a steel pipe arch deformation detection device of the application.

[0066] Figure 4 is a schematic diagram of a use state of a steel pipe arch deformation detection device of the application.

[0067] Figure 5 is Figure 4 an enlarged schematic diagram of A of

[0068] In the figure: 1-steel pipe, 2-detection robot, 3-steel sheet, 4-ring disc, 5-extension frame, 6-driving roller, 7-connection shaft, 8-second spring, 9-fixed connection unit, 10-hollow column, 11-movable shaft, 12-deformation detection mechanism, 13-infrared distance meter, 14-path recorder, 15-rack, 16-sliding sheet, 17-first spring, 18-first air cylinder, 19-knocking plate, 20-knocking hammer, 21-recording unit, 22-analysis unit. DETAILED DESCRIPTION

[0069] As Figures 1-5As shown, a steel pipe arch deformation detection device, comprising: a walking track and a detection robot 2, the walking track is arranged on the steel pipe arch of a steel pipe 1, the walking track comprises two L-shaped steel sheets 3, the steel sheet 3 is fixedly connected with the steel pipe arch, and the two steel sheets 3 are connected with the steel pipe arch to form a walking track; the detection robot 2 moves on the walking track, the detection robot 2 comprises a walking mechanism, a void detection mechanism and a deformation detection mechanism 12, the walking mechanism moves on the walking track, the walking mechanism comprises two rotating frames, the rotating frame comprises a ring disc 4 and four telescopic frames 5, the four telescopic frames 5 are distributed on the side surface of the ring disc 4 in pairs, the four telescopic frames 5 are combined to form an X-shaped structure, one end of the telescopic frame 5 is slidably connected with the ring disc 4, the other end of the telescopic frame 5 is provided with a driving roller 6, the driving roller 6 is in contact with the steel sheet 3 of the walking track, a second spring 8 is arranged between the adjacent two telescopic frames 5, a connecting shaft 7 is arranged between the two ring discs 4, the two ring discs 4 are rotatably connected with the connecting shaft 7, a detection mechanism connecting device is arranged on the ring disc 4 on the walking mechanism and facing the outside of the steel pipe arch, the detection mechanism connecting device is fixedly connected with the void detection mechanism and the deformation detection mechanism 12, the detection mechanism connecting device comprises a fixed connection unit 9 and a movable connection unit, the fixed connection unit 9 is connected with the ring disc 4 and the void detection mechanism respectively, the movable connection unit is connected with the deformation detection mechanism 12, the movable connection unit comprises a hollow column 10 and a movable shaft 11 rotating in the hollow column 10, the hollow column 10 is sleeved with the fixed connection unit 9, the deformation detection mechanism 12 is arranged at the bottom of the movable shaft 11, the deformation detection mechanism 12 comprises an infrared range finder 13 and a path recorder 14, the void detection mechanism comprises a rack 15, a knocking unit, a recording unit 21 and an analysis unit 22, the rack 15 is fixedly connected with the fixed connection unit 9, a first air cylinder 18 is arranged in the rack 15, one end of the first air cylinder 18 is connected with the knocking unit, the knocking unit comprises a knocking plate 19 and a knocking hammer 20, the bottom of the knocking plate 19 is fixedly connected with the telescopic end of the first air cylinder 18, a plurality of knocking hammers 20 are fixedly connected with the top of the knocking plate 19, the recording unit 21 and the analysis unit 22 are arranged in the rack 15.

[0070] Preferably, the side surface of the ring disc 4 is provided with a groove slide rail, one end of the telescopic frame 5 is provided with a sliding piece 16, and the sliding piece 16 slides on the groove slide rail.

[0071] Preferably, the fixed connection unit 9 is a circular sleeve structure, one end of the fixed connection unit 9 is sleeved with the hollow column 10, the other end of the fixed connection unit 9 is rotatably connected with the ring disc 4 through a plurality of supporting rods, one end of the supporting rod is in contact with the inner wall of the fixed connection unit 9, and the other end of the supporting rod is fixedly connected with the disc surface of the ring disc 4.

[0072] Preferably, the recording unit 21 comprises a microphone and a low-noise amplifier (operational amplifier LM358), and the analysis unit 22 is an STM32 series microcontroller.

[0073] Preferably, the infrared distance sensor 13 is a ToF infrared distance sensor (Sharp GP2Y0A series or VL53L0X or VL6180X according to actual conditions), and the path recorder 14 comprises an optical rotary encoder (AMS AS5048A) and an inertial measurement unit (MPU6050 or BNO055).

[0074] Preferably, the driving roller 6 is provided with a driving motor (Maxon DCX series), and the driving motor is connected with the driving roller 6 through a transmission gear.

[0075] A deformation detection method of a steel pipe arch deformation detection device, comprising the following steps:

[0076] Step 1, robot walking and path recording, comprising the following steps:

[0077] Step 1.1, placing the detection robot 2: placing the walking mechanism of the detection robot 2 in the track composed of steel sheets 3, and ensuring that the driving roller 6 is tightly pressed against the inner wall of the steel sheet 3 under the action of the second spring 8;

[0078] Step 1.2, starting the walking mechanism: starting the driving roller 6, and the detection robot 2 starts moving along the walking track, and the path recorder 14 records the walking trajectory data (x i , y i ), and records a position point every fixed time interval Δt;

[0079] Step 2, starting the knocking unit and collecting sound data, comprising the following steps:

[0080] Step 2.1, starting the knocking unit: starting the first cylinder 18, and driving the knocking hammer 20 to knock the surface of the steel pipe 1 at a fixed frequency f c and a fixed force;

[0081] Step 2.2, recording sound by the recording unit: the recording unit 21 records the knocking sound signal s(t);

[0082] Step 2.3, sound frequency analysis: the analysis unit 22 performs Fourier transform on the knocking sound signal s(t) to obtain a frequency domain signal:

[0083]

[0084] Wherein, S(f) represents the amplitude in the frequency domain, which is used to identify the frequency characteristics of the knocking sound, s(t) represents the knocking sound signal, and f represents the frequency.

[0085] Frequency feature analysis, compare actual frequency peak f measured with preset threshold f threshold :

[0086] If |f measured -f ideal |> f threshold , determine that the point is empty;

[0087] Record the empty point position P i =(x i , y i , z i );

[0088] Step 3, infrared ranging and three-dimensional data fusion, including the following steps:

[0089] Step 3.1, collect ground distance: the infrared range finder 13 synchronously records the ground distance z i of each walking point;

[0090] Step 3.2, generate three-dimensional point cloud: combine the walking trajectory data (x i , y i ) provided by the path recorder 14 and the z i data provided by the infrared range finder 13 to generate a three-dimensional point cloud:

[0091] P i =(x i , y i , z i ),

[0092] Wherein, P i represents the three-dimensional coordinate point of the detection robot 2 at a certain position on the surface of the steel pipe arch;

[0093] Step 4, steel pipe arch curve fitting, including the following steps:

[0094] Step 4.1, fitting ideal curve: assuming that the ideal shape of the steel pipe arch is a quadratic surface, the model is:

[0095] z(x,y) = a0 + a1x + a2y + a3x 2 +a4y 2 +a5xy,

[0096] Wherein, z(x, y) represents the fitted ideal steel pipe arch height, x and y represent the horizontal coordinate and vertical coordinate provided by the path recorder 14 respectively, a0, a1, a2, a3, a4, a5 represent the fitting coefficients, which are solved by the least square method;

[0097] Step 4.2, Fitting parameter solving: minimize the error function J by least square method: i.e.:

[0098]

[0099] where J represents the error function, (x i , y i , z i ) represents the data points collected by the path recorder 14 and the infrared distance meter 13, and n represents the sample number;

[0100] The optimal fitting coefficients a0, a1, a2, a3, a4, a5 are obtained by minimizing the error function J, and the ideal steel pipe arch surface formula is obtained.

[0101] Step 5, Steel pipe arch deformation calculation, including the following steps:

[0102] Step 5.1, Deformation calculation: for each point P i , calculate the deviation between the actual value and the ideal fitting value: Δz i = z i - z(x i , y i ),

[0103] where z i represents the actual measurement value of the infrared distance meter 13, z(x i , y i ) represents the ideal fitting value, and Δz i represents the deformation of point i;

[0104] Step 5.2, statistical deformation data, including the maximum deformation and the average deformation, the expression of the maximum deformation is:

[0105]

[0106] where Δz max represents the maximum deformation, and Δz i represents the deformation of point i;

[0107] The expression of the average deformation is:

[0108]

[0109] where Δz mean represents the average deformation, Δz i represents the deformation of point i, and n represents the sample number;

[0110] Step 6, Analysis of void and deformation combination, including the following steps:

[0111] Step 6.1, void point marking: mark all void points (x i ,y i ,z i ), and separately count the deformation of the void position;

[0112] Step 6.2, deformation thermodynamic diagram: generate the deformation thermodynamic diagram of the steel pipe arch according to the distribution of the deformation Δz i , mark the void points and the maximum deformation area;

[0113] Step 7, system output, including the following steps:

[0114] Step 7.1, report generation: output the void points and their specific position information (x i , y i , z i ), and output the deformation data, including the maximum deformation and the average deformation;

[0115] Step 7.2, visualization: use three-dimensional visualization tools Matlab or ROS or OpenGL to generate a three-dimensional morphological diagram of the steel pipe arch, display the deformation thermodynamic diagram and mark the void points and the maximum deformation area;

[0116] Step 7.3, feedback report: set a threshold according to the deformation, trigger an alarm mechanism and prompt the operator to handle it in time.

[0117] The basic principles, main features and advantages of the present application are shown and described above, and those skilled in the art should understand that the present application is not limited by the above embodiments, the above embodiments and descriptions in the specification are only preferred examples of the present application, and are not intended to limit the present application, various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application, the scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A steel pipe buckling deformation detection device characterized by comprising: The utility model relates to a kind of steel pipe arch detection system, including: Walking track and detection robot (2), the walking track is arranged on the steel pipe arch of steel pipe (1), the walking track includes two pieces of L-shaped steel sheet (3) up and down, the steel sheet (3) is fixedly connected with steel pipe arch, and the two pieces of steel sheet (3) are connected with steel pipe arch to form walking track;The detection robot (2) moves in walking track, and the detection robot (2) includes walking mechanism, void detection mechanism and deformation detection mechanism (12), the walking mechanism moves on walking track, and walking mechanism includes two rotating frames, the rotating frame includes annular disc (4) and four telescopic frames (5), the four telescopic frames (5) are distributed in the side of annular disc (4) two by two, and the four telescopic frames (5) are jointly combined to form X-shaped structure, one end of the telescopic frame (5) is slidably connected with annular disc (4), the other end of the telescopic frame (5) is provided with drive roller (6), the drive roller (6) is in contact with the steel sheet (3) of walking track, second spring (8) is provided between the two adjacent telescopic frames (5), connecting shaft (7) is provided between two annular discs (4), and the two annular discs (4) are rotatably connected with connecting shaft (7), detection mechanism connecting device is provided on the annular disc (4) of walking mechanism towards the outside of steel pipe arch, and the void detection mechanism and deformation detection mechanism (12) are fixedly connected on the detection mechanism connecting device, the detection mechanism connecting device includes fixed connection unit (9) and movable connection unit, the fixed connection unit (9) is connected with annular disc (4) and void detection mechanism respectively, and the movable connection unit is connected with deformation detection mechanism (12), the movable connection unit includes hollow column (10) and movable shaft (11) that rotates in hollow column (10), the hollow column (10) is sleeved with fixed connection unit (9), and deformation detection mechanism (12) is arranged at the bottom of movable shaft (11), and the deformation detection mechanism (12) includes infrared range finder (13) and path recorder (14), the void detection mechanism includes rack (15), knocking unit, recording unit (21) and analysis unit (22), the rack (15) is fixedly connected with fixed connection unit (9), and first air cylinder (18) is arranged in the rack (15), one end of the first air cylinder (18) is connected with knocking unit, the knocking unit includes knocking plate (19) and knocking hammer (20), the bottom of knocking plate (19) is fixedly connected with the telescopic end of first air cylinder (18), and a plurality of knocking hammers (20) are fixedly connected with the top of knocking plate (19), and recording unit (21) and analysis unit (22) are arranged in the rack (15).

2. The steel pipe arch deformation detection device according to claim 1, characterized by Groove slide rail is provided on the side of annular disc (4), one end of telescopic frame (5) is provided with sliding sheet (16), and sliding sheet (16) slides on groove slide rail.

3. The steel pipe arch deformation detection device according to claim 1, characterized by The fixed connection unit (9) is a circular sleeve structure, one end of the fixed connection unit (9) is sleeved with a hollow column (10), and the other end of the fixed connection unit (9) is rotatably connected with the annular disc (4) through a plurality of support rods, one end of the support rod is connected with the inner wall of the fixed connection unit (9), and the other end of the support rod is fixedly connected with the disc surface of the annular disc (4).

4. The steel pipe arch deformation detection device according to claim 1, characterized by The recording unit (21) comprises a microphone and a low-noise amplifier, and the analysis unit (22) is an STM32 series microcontroller.

5. The apparatus for detecting deformation of a steel pipe arch according to claim 1, wherein The infrared distance meter (13) is a ToF infrared distance meter, and the path recorder (14) comprises an optical rotary encoder and an inertial measurement unit.

6. The apparatus for detecting deformation of a steel pipe arch according to claim 1, wherein A driving motor is arranged on the driving roller (6), and the driving motor is connected with the driving roller (6) through a transmission gear.

7. A method of detecting the deformation of the steel pipe arch deformation detection apparatus according to claim 1, characterized by, The method comprises the following steps: Step 1, robot walking and path recording, comprising the following steps: Step 1.1, placing the detection robot (2): placing the walking mechanism of the detection robot (2) in the track composed of the steel sheet (3), ensuring that the driving roller (6) is tightly pressed against the inner wall of the steel sheet (3) under the action of the second spring (8); Step 1.2, starting walking mechanism: start driving roller (6), detect robot (2) to start moving along walking track, path recorder (14) records walking track data (x i ,y i ), record a position point every fixed time interval Δt; Step 2, starting of the knocking unit and sound data acquisition, comprising the following steps: Step 2.1, Start the knocking unit: Start the first cylinder (18) and drive the knocking hammer (20) at a fixed frequency f c and strike the surface of the steel pipe (1) with a fixed force. Step 2.2, recording sound by the recording unit: the recording unit (21) records the knocking sound signal s(t); Step 2.3, sound frequency analysis: the analysis unit (22) performs Fourier transform on the knocking sound signal s(t) to obtain a frequency domain signal: Wherein, S(f) represents the amplitude in the frequency domain, used to identify the frequency characteristics of the knocking sound, s(t) represents the knocking sound signal, and f represents the frequency; Analyze frequency characteristics, compare actual frequency peak f measured with preset threshold f threshold : if |f measured -f ideal |>f threshold then it is determined that the point is void; Recording the position P of the void point i = (x i , y i , z i ); Step 3, infrared distance measurement and three-dimensional data fusion, comprising the following steps: Step 3.1, Collecting ground distance: The infrared distance sensor (13) records the ground distance z at each walking point synchronously i ; Step 3.2, generating a three-dimensional point cloud: combine the walking trajectory data (x i ,y i ) provided by the path logger (14) and the z i data provided by the infrared distance sensor (13) to generate a three-dimensional point cloud: P i = (x i , y i , z i ), where P i represents the three-dimensional coordinate point of the detection robot (2) at a certain position on the surface of the steel pipe arch; Step 4, steel pipe arch curve fitting, comprising the following steps: Step 4.1, fitting ideal curve: assuming that the ideal shape of the steel pipe arch is a quadratic surface, the model is: z(x,y) = a0+ a1x + a2y + a3x 2 +a4y 2 +a5xy, Wherein, z(x, y) represents the fitted ideal steel pipe arch height, x and y represent the horizontal coordinate and vertical coordinate provided by the path recorder (14) respectively, a0, a1, a2, a3, a4, a5 represent the fitting coefficients, which are solved by the least square method; Step 4.2, Fitting parameter solution: Minimize the error function by least square method: i.e.: where J denotes the error function, (x i , y i , z i ) denotes the data points collected by the path recorder (14) and the infrared distance meter (13), and n denotes the number of samples. The optimal fitting coefficients a0, a1, a2, a3, a4, a5 are obtained by minimizing the error function J, and then the surface formula of the ideal steel pipe arch is obtained. Step 5, steel pipe arch deformation calculation, comprising the following steps: Step 5.1, deformation quantity calculation: for each point P i , the deviation between the actual value and the fitted ideal value is calculated: Δz i = z i - z(x i , y i ), where z i represents the actual measured value of the infrared distance meter (13), z(x i , y i ) represents the fitted ideal value, Δz i represents the deformation amount of the point i; Step 5.2, statistical deformation data, including the maximum deformation and the average deformation, the expression of the maximum deformation is: where Δz max represents the maximum deformation, Δz i represents the deformation of point i; The expression of the average deformation is: where Δz mean represents the average deformation, Δz i represents the deformation of point i, and n represents the number of samples. Step 6, analysis of void and deformation combination, comprising the following steps: Step 6.1, void point marking: mark all void points (x i , y i , z i ), and count the deformation of void position separately; Step 6.2, deformation thermal map: generate the deformation thermal map of the steel tube arch according to the distribution of the deformation variable Δz i , mark out the void point and the maximum deformation region; Step 7, system output, comprising the following steps: Step 7.1, Generating Report: output the voids and their specific location information (x i ,y i ,z i ), output the deformation data, including the maximum deformation and the average deformation; Step 7.2, visualization: using three-dimensional visualization tools Matlab or ROS or OpenGL to generate a three-dimensional shape diagram of the steel pipe arch, displaying a deformation thermal map and marking the void points and the maximum deformation area; Step 7.3, feedback report: setting a threshold value according to the deformation, triggering an alarm mechanism and prompting the operator to handle it in time.

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