A TBM tunnel face contour recognition device and method based on line laser measurement

Abstract

The present invention discloses a TBM tunnel face contour recognition device and method based on line laser measurement. A high-precision line laser measuring instrument rotates with the cutter head, and a rotation angle encoder is used to measure the real-time rotation angle, thereby achieving full coverage, efficient and high-precision measurement of the geological characteristics and morphology of the TBM tunnel face. With the help of an automatic window switch device, the line laser measuring instrument can be effectively protected and the opening required for each shooting can be guaranteed. At the same time, the electric slip ring in the TBM machine is used to solve the power supply and data effective transmission problems during the rotation of the sensor, thereby ensuring the continuity, safety, stability and accuracy of the measurement process. Finally, Matlab linear interpolation is used to achieve three-dimensional reconstruction of the full spatial range of the face and a corresponding calculation method is designed to achieve three-dimensional reconstruction and contour recognition of the geological characteristics and morphology of the TBM tunnel face, ultimately facilitating the calculation of the rock breaking volume during TBM excavation construction, thereby providing important data support for quantitative evaluation of excavation efficiency.

Description

Technical Field

[0001] The invention belongs to the field of tunnel and underground engineering measurement, and in particular to a TBM tunnel face contour recognition device and method based on line laser measurement. Background Art

[0002] The first requirement for safe and efficient excavation of TBM tunnels is to be able to perceive the geological characteristics and morphology of the face in real time. The face contains a lot of geological information. If it can be fully extracted and analyzed, it will help to evaluate the geological status of the tunnel engineering and adjust the TBM excavation parameters in time. The face is usually in a black box state, with a harsh working environment and narrow space, which puts high demands on the perception and extraction of the face contour and morphology. In actual engineering, due to the limitations of site conditions and technical conditions, in most cases, the geological information of the face is still described by technicians according to the established recording format requirements, which puts high demands on the experience and level of technicians, will cause deviations in the description of the face, and there will also be delays, and it is impossible to provide timely guidance for construction, which is obviously not suitable for the face of TBM tunnels. The current common means of photogrammetry and digital imaging also have relatively high requirements for environmental conditions. When the environmental conditions are harsh (insufficient light source, etc.), the image quality will be seriously affected, and the geological characteristics and morphology of the face cannot be accurately obtained. In addition, due to the small distance between the cutterhead and the face, the face cannot be completely covered by high-definition cameras, and there are local blind spots. It is worth noting that since the shield machine cutterhead is a rotating mechanism, it is difficult to power the sensor and transmit data, which is also an important bottleneck restricting the real-time perception of the TBM tunnel face. Currently, there are almost no reports on the real-time and accurate calculation of rock breaking volume during actual TBM construction, and the calculation of rock breaking volume is crucial to evaluating rock breaking efficiency.

[0003] Due to the small space and harsh geological environment, high requirements are placed on real-time perception technology and equipment. Photogrammetry and digital images are difficult to accurately capture the geological characteristics and morphology of the face. The particularity between the rotating mechanism and the static object also places high requirements on sensor power supply and data transmission. In addition, the accurate calculation of rock breaking volume in TBM excavation construction is still a blank field, which is intuitive and important for the evaluation of rock breaking efficiency.

[0004] Therefore, how to achieve three-dimensional reconstruction and contour recognition of the geological characteristics and morphology of the TBM tunnel face through full coverage, high efficiency and high-precision continuous measurement, and accurately obtain the rock broken volume during the excavation process, is the research direction required by the present invention. Summary of the invention

[0005] In response to the problems existing in the above-mentioned prior art, the present invention provides a TBM tunnel face contour recognition device and method based on line laser measurement, which realizes three-dimensional reconstruction and contour recognition of the geological characteristics and morphology of the TBM tunnel face through full coverage, high efficiency and high-precision continuous measurement, and can accurately obtain the rock broken volume during the excavation process.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a TBM tunnel face contour recognition device based on line laser measurement, including a high-precision line laser measuring instrument, a window automatic switch device, an angle encoder, and a data processing device.

[0007] The high-precision line laser measuring instrument is embedded in the cutterhead of the TBM machine and is used to emit a line laser through an opening on the cutterhead toward the tunnel face for scanning; and the length of the line laser emitted each time can cover the radius of the tunnel face, and the end point of one end of the line laser is located at the center of the tunnel face.

[0008] The window automatic switch device is installed at the opening of the cutter disc, which can be opened when the high-precision line laser measuring instrument emits line laser detection and closed after completion, and is used to protect the high-precision line laser measuring instrument when no detection is performed.

[0009] The angle encoder is mounted on the rotating shaft of the cutter disc and is used to record the rotation angle of the cutter disc, thereby determining the real-time angle and orientation of the line laser scanning.

[0010] The data processing device is placed in the TBM machine. When performing detection, the window automatic switch device is turned on, the high-precision line laser measuring instrument emits a line laser for scanning, and the reflected line laser scanning data is received in real time; the cutter head is rotated at a constant speed, and the angle encoder records the rotation angle of the cutter head in real time until the cutter head rotates one circle, then the window automatic switch device and the high-precision line laser measuring instrument are turned off, the data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutter head rotation angle data recorded by the angle encoder, and after analysis and processing, the tunnel face is three-dimensionally reconstructed to realize the tunnel face contour recognition.

[0011] Furthermore, the specification parameters of the line laser measuring instrument are determined according to the diameter of the tunnel.

[0012] Furthermore, the automatic window opening and closing device is an existing structure, which includes a motor and a baffle, wherein the motor is used to drive the baffle to close or open the window, and the operation of the motor is controlled by the switch. This structure is not only stable in operation, but also easy to control.

[0013] Furthermore, the high-precision line laser measuring instrument and the cutter head angle encoder are connected to the data processing device through a data cable. A cable groove is opened on the cutter head of the TBM machine, so that the data cable is connected to the data processing device after passing through the cable groove and the electric slip ring in the TBM machine; the electric slip ring is an existing structure in the TBM machine, and the electric slip ring can connect the wires respectively led out from the stator and the rotor parts to the fixed structure and the rotating structure and rotate with them. In this way, the problem of continuous power supply and effective data transmission during the rotation of the sensor is solved.

[0014] The high-precision line laser measuring instrument and the cutter head angle encoder are both connected to the data processing device via data cables. A wire groove is provided on the cutter head of the TBM machine so that the data cable is connected to the data processing device after passing through the wire groove and the slip ring.

[0015] Furthermore, the data processing device is a computer.

[0016] The working method of the TBM tunnel face contour recognition device based on line laser measurement is specifically as follows:

[0017] A. When the TBM is not in the excavation state, first remove the dust and rock debris near the tunnel face to avoid affecting the laser signal transmission, and keep the cutter head of the TBM machine 0.6 to 0.7m away from the tunnel face.

[0018] B. Start identifying the tunnel face contour by rotating the cutterhead at a speed of 0.1 r / min and wait for the cutterhead to start rotating at a uniform speed.

[0019] C. After the cutterhead starts to rotate at a uniform speed, first open the automatic window switch device and start the high-precision line laser measuring instrument. At this time, the high-precision line laser measuring instrument emits a line laser. Before officially starting the laser scanning, you should check whether the laser covers the radius and center position of the tunnel face based on the signal feedback. If not, you should adjust the position of the high-precision line laser measuring instrument.

[0020] D. Officially start laser scanning. At this time, the rotation angle of the cutterhead is recorded in real time through angle coding. When the cutterhead rotates one circle at a speed of 0.1r / min, the scanning stops, and the window automatic switch device and the high-precision line laser measuring instrument are closed. The data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutterhead rotation angle data recorded by the angle encoder. The line laser scanning data is divided by angle, and each angle corresponds to a txt folder. The txt folder includes the line coordinates and absolute elevation data at the current angle. The subsequent data processing device reconstructs the contour of the current tunnel face in three dimensions through analysis and processing to realize the contour recognition of the tunnel face.

[0021] E. Finish the contour recognition work of the current tunnel face, and the TBM continues to excavate the tunnel until it is in a non-excavation state again after excavating a certain distance. Then, repeat steps A to D to perform three-dimensional reconstruction of the contour of the current tunnel face to realize the contour recognition of the tunnel face.

[0022] F. Analyze and process the tunnel face profile data obtained twice before and after, so as to obtain the volume of rock broken during this excavation process.

[0023] Furthermore, the three-dimensional reconstruction of the contour of the current tunnel face in step D is specifically as follows: the line laser scanning data is composed of point data in polar coordinate form, and the point data content includes: polar coordinates, absolute elevation and cutter head angle; the polar coordinates are converted into rectangular coordinates through angle conversion; then linear interpolation is performed through Matlab, the actual coordinate points are interpolated to the interpolation points, and the original uneven data points are converted into uniform radial points with equal radial spacing, and its boundary is the innermost boundary that can be scanned by the high-precision line laser measuring instrument; all data points are reconstructed in three dimensions to restore the three-dimensional contour of the current tunnel face.

[0024] Furthermore, the specific process of analyzing and processing the tunnel face contour data obtained twice in step F is: multiplying the area of ​​the quadrilateral composed of four adjacent interpolation points by the difference in the average absolute elevation of the same four points of the tunnel face twice, and then summing all the quadrilaterals to obtain the volume of rock broken during this excavation process. The specific formula is:

[0025]

[0026] In the formula, V is the volume of rock breaking, n is the number of quadrilaterals, S is the area of ​​the quadrilaterals, is the difference between the average absolute elevations of the same four points on the tunnel face before and after. The calculation process to obtain this value is as follows: (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) are the coordinates of the four adjacent interpolation points A1, A2, A3, A4, respectively. The absolute elevation values ​​of the four points obtained in the previous laser scan are Z 11 , Z 12 , Z 13 , Z 14 , and obtain the absolute elevation values ​​of these four points in this laser scanning: Z 21 , Z 22 , Z 23 , Z 24 , calculate the difference between the absolute elevations of the tunnel face twice before and after each of the four points, and finally average the difference of the four points to get value.

[0027] Compared with the prior art, the present invention realizes full coverage, efficient and high-precision measurement of the geological characteristics and morphology of the TBM tunnel face by using a high-precision line laser measuring instrument to rotate with the cutter head of the shield machine and to measure the real-time rotation angle through a rotation angle encoder; the line laser measuring instrument can be effectively protected and the opening required for each shooting can be guaranteed by means of an automatic window switch device, and the power supply problem and the effective data transmission problem during the rotation of the sensor are solved by using the function of the electric slip ring in the TBM machine, thereby ensuring the continuity, safety, stability and accuracy of the measurement process; finally, Matlab linear interpolation is used to realize three-dimensional reconstruction of the entire spatial range of the face and a corresponding calculation method is designed to realize three-dimensional reconstruction and contour recognition of the geological characteristics and morphology of the TBM tunnel face, which ultimately facilitates the calculation of the rock breaking volume during TBM excavation construction, providing important data support for quantitative evaluation of excavation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the principle of the device in the present invention.

[0029] Figure 2 It is a schematic diagram of the centerline laser on the palm face of the present invention.

[0030] Figure 3 It is a schematic diagram of the rock breaking volume calculation principle in the present invention.

[0031] Figure 4 It is a flow chart of the three-dimensional reconstruction of the tunnel face and the calculation of the rock breaking volume in the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below.

[0033] like Figure 1 As shown, a TBM tunnel face contour recognition device based on line laser measurement includes a high-precision line laser measuring instrument, a window automatic switch device, an angle encoder, and a data processing device.

[0034] The high-precision line laser measuring instrument is embedded in the cutterhead of the TBM machine and is used to emit a line laser through an opening on the cutterhead toward the tunnel face for scanning; Figure 2 As shown, the length of the line laser emitted each time can cover the radius of the tunnel face, and the end point of one end of the line laser is located at the center of the tunnel face; the specification parameters of the line laser measuring instrument are determined according to the diameter of the tunnel.

[0035] The automatic window switch device is installed at the opening on the cutter disc. It can be opened when the high-precision line laser measuring instrument emits line laser detection and closed after completion. It is used to protect the high-precision line laser measuring instrument when no detection is performed. It is an existing structure, including a motor and a baffle. The motor is used to drive the baffle to move to close or open the window, and the operation of the motor is controlled by the switch.

[0036] The angle encoder is mounted on the rotating shaft of the cutter disc and is used to record the rotation angle of the cutter disc, thereby determining the real-time angle and orientation of the line laser scanning.

[0037] The data processing device is placed in the TBM machine, and the data processing device is a computer. When detecting, the window automatic switch device is turned on, the high-precision line laser measuring instrument emits a line laser for scanning, and the reflected line laser scanning data is received in real time. The cutter head rotates at a constant speed, and the angle encoder records the rotation angle of the cutter head in real time until the cutter head rotates one circle, and then the window automatic switch device and the high-precision line laser measuring instrument are turned off. The data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutter head rotation angle data recorded by the angle encoder, and performs three-dimensional reconstruction of the tunnel face after analysis and processing, so as to realize the tunnel face contour recognition. The high-precision line laser measuring instrument and the cutter head angle encoder are both connected to the data processing device through a data cable, and a cable groove is opened on the cutter head of the TBM machine, so that the data cable is connected to the data processing device after passing through the cable groove and the electric slip ring in the TBM machine; wherein the electric slip ring is an existing structure in the TBM machine, and the electric slip ring can connect the wires respectively led out of the stator and the rotor parts to the fixed structure and the rotating structure and rotate therewith, and in this way, the problem of continuous power supply and effective data transmission during the rotation of the sensor is solved.

[0038] like Figure 3 and 4 As shown, the working method of the TBM tunnel face contour recognition device based on line laser measurement is specifically as follows:

[0039] A. When the TBM is not in the excavation state, first remove the dust and rock debris near the tunnel face to avoid affecting the laser signal transmission, and keep the cutter head of the TBM machine 0.6 to 0.7m away from the tunnel face.

[0040] B. Start identifying the tunnel face contour by rotating the cutterhead at a speed of 0.1 r / min and wait for the cutterhead to start rotating at a uniform speed.

[0041] C. After the cutterhead starts to rotate at a uniform speed, first open the window automatic switch device and start the high-precision line laser measuring instrument. At this time, the high-precision line laser measuring instrument emits a line laser. Before officially starting the laser scanning, you should check whether the laser covers the radius and center position of the tunnel face based on the signal feedback. If not, you should adjust the position of the high-precision line laser measuring instrument;

[0042] D. Officially start laser scanning. At this time, the rotation angle of the cutterhead is recorded in real time through angle coding. When the cutterhead rotates one circle at a speed of 0.1r / min, the scanning stops, the window automatic switch device and the high-precision line laser measuring instrument are closed, and the data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutterhead rotation angle data recorded by the angle encoder. The line laser scanning data is divided by angle, and each angle corresponds to a txt folder. The txt folder includes the line coordinates and absolute elevation data at the current angle. The subsequent data processing device analyzes and processes the current tunnel face. The contour is reconstructed in three dimensions to realize the contour recognition of the tunnel face. Specifically, the line laser scanning data is composed of point data in polar coordinate form, and the point data content includes: polar coordinates, absolute elevation and cutter head angle; the polar coordinates are converted into rectangular coordinates through angle conversion; then linear interpolation is performed through Matlab to interpolate the actual coordinate points to the interpolation points, and the original uneven data points are converted into uniform radial points with equal radial spacing, and its boundary is the innermost boundary that can be scanned by the high-precision line laser measuring instrument; all data points are reconstructed in three dimensions to restore the three-dimensional contour of the current tunnel face.

[0043] E. Finish the contour recognition work of the current tunnel face, and the TBM continues to excavate the tunnel until it is in a non-excavation state again after excavating a certain distance. Then, repeat steps A to D to perform three-dimensional reconstruction of the contour of the current tunnel face to realize the contour recognition of the tunnel face.

[0044] F. Analyze and process the tunnel face contour data obtained twice. The specific process is: multiply the area of ​​the quadrilateral composed of four adjacent interpolation points by the difference in the average absolute elevation of the same four points of the tunnel face twice, and then sum all the quadrilaterals to obtain the volume of rock broken during this excavation process. The specific formula is:

[0045]

[0046] In the formula, V is the volume of rock breaking, n is the number of quadrilaterals, S is the area of ​​the quadrilaterals, is the difference between the average absolute elevations of the same four points on the tunnel face before and after. The calculation process to obtain this value is as follows: (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) are the coordinates of the four adjacent interpolation points A1, A2, A3, A4, respectively. The absolute elevation values ​​of the four points obtained in the previous laser scan are Z 11 , Z 12 , Z 13 , Z 14 , and obtain the absolute elevation values ​​of these four points in this laser scanning: Z 21 , Z 22 , Z 23 , Z 24 , calculate the difference between the absolute elevations of the tunnel face twice before and after each of the four points, and finally average the difference of the four points to get value.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A TBM tunnel face contour recognition device based on line laser measurement, characterized in that: It includes a high-precision line laser measuring instrument, an automatic window switch device, an angle encoder, and a data processing device; The high-precision line laser measuring instrument is embedded in the cutterhead of the TBM machine, and is used to emit a line laser toward the tunnel face through an opening on the cutterhead for scanning; and the length of the line laser emitted each time can cover the radius of the tunnel face, and one end of the line laser is located at the center of the tunnel face; The window automatic switch device is installed at the opening of the cutter head, which can be opened when the high-precision line laser measuring instrument emits line laser detection and closed after completion, and is used to protect the high-precision line laser measuring instrument when no detection is performed; The angle encoder is mounted on the rotating shaft of the cutter disc and is used to record the rotation angle of the cutter disc, thereby determining the real-time angle and orientation of the line laser scanning; The data processing device is placed in the TBM machine. When performing detection, the window automatic switch device is turned on, the high-precision line laser measuring instrument emits a line laser for scanning, and the reflected line laser scanning data is received in real time; the cutter head is rotated at a constant speed, and the angle encoder records the rotation angle of the cutter head in real time until the cutter head rotates one circle, then the window automatic switch device and the high-precision line laser measuring instrument are turned off, the data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutter head rotation angle data recorded by the angle encoder, and after analysis and processing, the tunnel face is three-dimensionally reconstructed to realize the tunnel face contour recognition.

2. The TBM tunnel face contour recognition device based on line laser measurement according to claim 1 is characterized in that: The specification parameters of the line laser measuring instrument are determined according to the diameter of the tunnel.

3. The TBM tunnel face contour recognition device based on line laser measurement according to claim 1 is characterized in that: The automatic window opening and closing device comprises a motor and a baffle, wherein the motor is used to drive the baffle to move to close or open the window.

4. The TBM tunnel face contour recognition device based on line laser measurement according to claim 1 is characterized in that: The high-precision line laser measuring instrument and the cutter head angle encoder are both connected to the data processing device via data cables. A cable groove is provided on the cutter head of the TBM machine, so that the data cable is connected to the data processing device after passing through the cable groove and the electric slip ring in the TBM machine.

5. The TBM tunnel face contour recognition device based on line laser measurement according to claim 1 is characterized in that: The data processing device is a computer.

6. A working method of the TBM tunnel face contour recognition device based on line laser measurement according to any one of claims 1 to 5, characterized in that: The specific steps are: A. When the TBM is not in the excavation state, first remove the dust and rock debris near the tunnel face to avoid affecting the laser signal transmission, and keep the cutter head of the TBM machine 0.6 to 0.7m away from the tunnel face; B. Start tunnel face contour recognition. First, rotate the cutterhead at a speed of 0.1r / min and wait for the cutterhead to start uniform rotation. C. After the cutterhead starts to rotate at a uniform speed, first open the window automatic switch device and start the high-precision line laser measuring instrument. At this time, the high-precision line laser measuring instrument emits a line laser. Before officially starting the laser scanning, you should check whether the laser covers the radius and center position of the tunnel face based on the signal feedback. If not, you should adjust the position of the high-precision line laser measuring instrument; D. The laser scanning is officially started. At this time, the rotation angle of the cutterhead is recorded in real time through angle coding. When the cutterhead rotates one circle at a speed of 0.1r / min, the scanning stops. The window automatic switch device and the high-precision line laser measuring instrument are closed. The data processing device receives the line laser scanning data collected by the high-precision line laser measuring instrument and the cutterhead rotation angle data recorded by the angle encoder. The line laser scanning data is divided by angle. Each angle corresponds to a txt folder. The txt folder includes the line coordinates and absolute elevation data at the current angle. The subsequent data processing device reconstructs the contour of the current tunnel face in three dimensions through analysis and processing to realize the contour recognition of the tunnel face. E. The contour recognition work of the current tunnel face is finished, and the TBM continues to excavate the tunnel until it is in a non-excavation state again after excavating a certain distance, and then repeats steps A to D to perform three-dimensional reconstruction of the contour of the current tunnel face to realize the contour recognition of the tunnel face; F. Analyze and process the tunnel face profile data obtained twice before and after, so as to obtain the volume of rock broken during this excavation process.

7. The working method according to claim 6, characterized in that: The three-dimensional reconstruction of the contour of the current tunnel face in step D is specifically as follows: the line laser scanning data is composed of point data in polar coordinate form, and the point data content includes: polar coordinates, absolute elevation and cutter head angle; the polar coordinates are converted into rectangular coordinates through angle conversion; then linear interpolation is performed through Matlab, the actual coordinate points are interpolated to the interpolation points, and the original uneven data points are converted into uniform radial points with equal radial spacing, and the boundary is the innermost boundary that can be scanned by the high-precision line laser measuring instrument; all data points are reconstructed in three dimensions to restore the three-dimensional contour of the current tunnel face.

8. The working method according to claim 6, characterized in that: The specific process of analyzing and processing the tunnel face contour data obtained twice in step F is: multiplying the area of ​​the quadrilateral composed of four adjacent interpolation points by the difference in the average absolute elevation of the same four points of the tunnel faces twice, and then summing all the quadrilaterals to obtain the volume of rock broken during this excavation process. The specific formula is: In the formula, V is the volume of rock breaking, n is the number of quadrilaterals, S is the area of ​​the quadrilaterals, is the difference between the average absolute elevations of the same four points on the tunnel face before and after. The calculation process to obtain this value is as follows: (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) are the coordinates of the four adjacent interpolation points A1, A2, A3, A4, respectively. The absolute elevation values ​​of the four points obtained in the previous laser scan are Z 11 , Z 12 , Z 13 , Z 14 , and obtain the absolute elevation values ​​of these four points in this laser scanning: Z 21 , Z 22 , Z 23 , Z 24 , calculate the difference between the absolute elevations of the tunnel face twice before and after each of the four points, and finally average the difference of the four points to get value.

Images