Electromechanical vision measuring device for shield tail gap of shield tunneling machine

Abstract

The utility model relates to the technical field of tail shield gap measurement of a shield tunneling machine, in particular to an electromechanical vision measurement device for a tail shield gap of a shield tunneling machine. The shield tail gap measuring device comprises a fixing frame and a measuring mechanism, the fixing frame is mounted on a shield tunneling machine, the measuring mechanism is mounted on the fixing frame, and the measuring mechanism is used for converting a shield tail gap value into a moving position of a sliding table through matching of a point laser and a camera, so that accurate measurement of the shield tail gap of the shield tunneling machine is realized; a spot laser and a sliding table on a measuring mechanism irradiate a shield tail gap to generate light spots with different gray levels, then a gray level image is subjected to rotation and filtering processing, the position of the sliding table is contrasted, the direct relation between the light spot pixel position and the actual displacement of the sliding table is solved, and primary positioning of the position of a red light spot is achieved. And the gap value of the shield tail is calculated according to the moving distance of the sliding table from the appearance of the light spot to the disappearance of the light spot, so that the gap value of the shield tail can be directly measured by adopting the mode, manual operation is avoided, and the measurement accuracy is further ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of shield machine tail shield gap measurement, in particular to a shield machine tail shield gap electromechanical visual measurement device. Background Art

[0002] At present, the commonly used shield tail gap measurement methods are non-contact measurement, including the method of pre-embedded ultrasonic sensors in the shield tail shell near the shield tail brush position to measure the shield tail gap and the method of measuring by camera vision algorithm. Both methods have great defects: pre-embedded ultrasonic sensors are difficult to construct and require cutting and welding of the shield tail shell. On-site construction faces safety issues such as high-altitude operations and the quality of internal and external repairs after the tail shield is cut through; ultrasonic sensors have a measurement blind spot and cannot reliably measure the situation where the shield tail gap is small. It is necessary to ensure that the pipe segment directly in front is outside the blind spot of the ultrasonic sensor to ensure the measurement accuracy; the ultrasonic sensor probe transmits and receives ultrasonic waves, and the on-site probe is often stained with water or mud and cannot work properly. The camera vision algorithm measurement method avoids the above defects, but the camera vision is affected by the complex light on site, and often cannot distinguish between the shield tail gap and the pipe segment sealing rubber ring during the edge detection algorithm. After image processing and binarization, both have approximately the same low grayscale value; during the excavation of each ring of the shield machine, the distance between the camera lens and the pipe segment is constantly increasing. The measurement algorithm relies on the acquisition of the stroke of the shield machine's propulsion cylinder and requires continuous scale conversion. The scale requires professional visual algorithm personnel to calibrate on site. Usually, the scale data cannot be accurately obtained on site, resulting in large measurement errors.

[0003] Therefore, the present invention provides a shield tail gap electromechanical visual measuring device for a shield machine to solve the above problems. Utility Model Content

[0004] The technical problem to be solved by the utility model is as follows: the existing measurement algorithm relies on the acquisition of the thrust cylinder stroke of the shield machine, which requires continuous scale conversion. The scale requires professional visual algorithm personnel to calibrate on site. Usually, the scale data cannot be accurately obtained on site, resulting in large measurement errors.

[0005] The utility model provides the following technical solutions: an electromechanical visual measuring device for the shield tail gap of a shield machine, comprising a fixed frame, which is installed on the shield machine, and a measuring mechanism, which is installed on the fixed frame. The measuring mechanism is used to convert the shield tail gap value into the position of the slide movement through the cooperation of a point laser and a camera, thereby realizing accurate measurement of the shield tail gap of the shield machine.

[0006] Preferably, the measuring mechanism includes a measuring frame, a limit end block, a limit rod, a sliding table, an encoder stepper motor, an adjusting rod, an adjustable joint, and a dot laser. The measuring frame is fixedly installed on the fixed frame. Limit end blocks are installed on both sides of the measuring frame. A limit rod is installed between the limit end blocks. A sliding table is installed on the limit rod. An encoder stepper motor is installed on one side of the limit end block. An adjusting rod is installed on the sliding table. An adjustable joint is installed on the adjusting rod. A dot laser is installed on the adjustable joint.

[0007] Preferably, the adjustable joint includes a clamping block, a fixing bolt, an adjusting piece, and a clamping plate. The clamping blocks are symmetrically installed at the end of the adjusting rod, and fixing holes are provided on the clamping blocks. The fixing bolt passes through the fixing holes for fixation. An adjusting piece is installed at the other end of the clamping block. A clamping plate is installed on the adjusting piece.

[0008] Preferably, a camera is installed on the measuring mechanism.

[0009] Preferably, one end of the detection rod is spherical, and a zero position proximity switch is installed between the sliding table and the limit end block.

[0010] The beneficial effects of the present utility model are as follows:

[0011] 1. By setting up the measuring mechanism in the present utility model, with the dot laser and the sliding table on the measuring mechanism, the dot laser irradiates the shield tail gap, thereby generating light spots with different grayscales. Then, the grayscale image is rotated and filtered, and by comparing with the position of the sliding table, the relationship between the pixel position of the light spot and the actual displacement of the sliding table is solved, realizing the preliminary positioning of the position of the red light spot. And by the distance that the sliding table moves when the light spot appears to disappears, the shield tail gap value is calculated. Using this method, the shield tail gap value can be directly measured, avoiding manual operation, and thus ensuring the accuracy of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0013] Figure 1 is the overall schematic diagram of the present utility model;

[0014] Figure 2 is the schematic diagram of the measuring mechanism of the present utility model;

[0015] Figure 3Schematic diagram of the adjustable joint of the present utility model;

[0016] Figure 4 Schematic diagram of the dot laser of the present utility model.

[0017] In the figure: 1, fixing bracket; 2, measuring mechanism; 21, measuring bracket; 22, limiting end block; 23, limiting rod; 24, sliding table; 25, stepping motor with encoder; 26, adjusting rod; 27, adjustable joint; 271, clamping block; 2711, fixing hole; 272, fixing bolt; 273, adjusting piece; 274, clamping plate; 28, dot laser; 3, camera; 4, zero position proximity switch. Specific embodiments

[0018] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. Therefore, the detailed description of the embodiments of the present utility model below is not intended to limit the scope of the present utility model claimed, but merely represents some embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0019] It should be noted that: like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0020] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "rear", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is customarily placed during use. Such terms are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

[0021] It should also be noted that in the description of the present utility model, unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0022] The embodiments of the present disclosure aim to solve the problem that the existing measurement algorithm depends on the acquisition of the stroke of the shield machine propulsion cylinder and requires continuous scale conversion. The scale needs to be calibrated by professional vision algorithm personnel on-site, and usually, the scale data cannot be accurately obtained on-site, resulting in a large measurement error. In view of this, the embodiments of the present disclosure propose a visual measurement device for the shield tail clearance of a shield machine. Through the dot laser and the sliding table on the measurement mechanism, the dot laser irradiates the shield tail clearance, thereby generating light spots with different grayscales. Then, the gray image is rotated and filtered, and by comparing the position of the sliding table, the relationship between the pixel position of the light spot and the actual displacement of the sliding table is solved, realizing the preliminary positioning of the position of the red light spot. And through the distance that the sliding table moves when the light spot appears and disappears, the clearance value of the shield tail is calculated. By using this method, the clearance value of the shield tail can be directly measured, avoiding manual operation, and thus ensuring the accuracy of the measurement.

[0023] As Figures 1 to 4 shown, a visual measurement device for the shield tail clearance of a shield machine includes a fixed frame 1, the fixed frame 1 is installed on the shield machine, and further includes a measurement mechanism 2, the measurement mechanism 2 is installed on the fixed frame 1, and the measurement mechanism 2 is used to convert the shield tail clearance value into the position where the sliding table 24 moves through the cooperation of the dot laser 28 and the camera 3, thereby realizing the accurate measurement of the shield tail clearance of the shield machine;

[0024] Through the dot laser 28 and the sliding table 24 on the measurement mechanism 2, the dot laser 28 irradiates the shield tail clearance, thereby generating light spots with different grayscales. Then, the gray image is rotated and filtered, and by comparing the position of the sliding table 24, the relationship between the pixel position of the light spot and the actual displacement of the sliding table 24 is solved, realizing the preliminary positioning of the position of the red light spot. And through the distance that the sliding table 24 moves when the light spot appears and disappears, the clearance value of the shield tail is calculated. By using this method, the clearance value of the shield tail can be directly measured, avoiding manual operation, and thus ensuring the accuracy of the measurement.

[0025] As Figure 1 and Figure 2As shown in the figure, the measuring mechanism 2 includes a measuring frame 21, a limiting end block 22, a limiting rod 23, a sliding table 24, a stepping motor with an encoder 25, an adjusting rod 26, an adjustable joint 27, and a dot laser 28. The measuring frame 21 is fixedly installed on the fixed frame 1, and the measuring frame 21 is used to fix the measuring mechanism 2. Limiting end blocks 22 are installed on both sides of the measuring frame 21, and the limiting end blocks 22 are used to limit the sliding table 24. A limiting rod 23 is installed between the limiting end blocks 22. The limiting rod 23 is used to restrict the displacement direction of the limiting end blocks 22 and at the same time drive the sliding table 24 to move by rotation. The sliding table 24 is installed on the limiting rod 23, and the sliding table 24 is used to move on the limiting rod 23 to cooperate with the camera 3 to complete the detection of the shield tail gap. A stepping motor with an encoder 25 is installed on one side of the limiting end block 22, and the stepping motor with an encoder 25 is used to control the rotation of the limiting rod 23 to drive the sliding table 24 to move back and forth. An adjusting rod 26 is installed on the sliding table 24, and the adjusting rod 26 is used to adjust the position of the dot laser 28. An adjustable joint 27 is installed on the adjusting rod 26, and the adjustable joint 27 is used to adjust the angle of the dot laser 28. The dot laser 28 is installed on the adjustable joint 27, and the dot laser 28 is used to emit laser into the shield tail gap.

[0026] During operation, the staff controls the rotation of the stepping motor with an encoder. The rotation of the stepping motor with an encoder drives the limiting rod 23 to rotate. The rotation of the limiting rod 23 drives the sliding table 24 to move on the measuring frame 21. The sliding table 24 drives the adjusting rod 26 to move up and down. The adjusting rod 26 moving up and down drives the adjustable joint 27 to move up and down. The adjustable joint 27 drives the dot laser 28 to move up and down, so that the dot laser 28 emits laser onto the shield tail gap.

[0027] As Figure 3 shown in the figure, the adjustable joint 27 includes a clamping block 271, a fixing bolt 272, an adjusting piece 273, and a clamping plate 274. The clamping blocks 271 are symmetrically installed at the ends of the adjusting rod 26, and the clamping blocks 271 are used to clamp the adjustable joint 27 onto the adjusting rod 26. And fixing holes 2711 are provided on the clamping blocks 271, and the fixing holes 2711 are used to cooperate with the fixing bolts 272 for fixation. The fixing bolts 272 pass through the fixing holes 2711 and are fixed. The fixing bolts 272 are used to fix the clamping blocks 271 on the adjusting rod 26. The adjusting piece 273 is installed at the other end of the clamping block 271, and the adjusting piece 273 is used to drive the dot laser 28 to rotate. The clamping plate 274 is installed on the adjusting piece 273, and the clamping plate 274 is used to limit the adjusting piece 273.

[0028] During operation, when the adjusting rod 26 drives the adjustable joint 27 to a specified position, the motor disposed inside the clamping block 271 drives the adjusting piece 273 to rotate at this time, and then the adjusting piece 273 drives the dot laser 28 to rotate, thereby realizing the angle adjustment of the dot laser 28.

[0029] As Figure 4 shown, a camera 3 is installed on the measuring mechanism 2. The camera 3 is used to collect images of the light spots on the end face of the segment and transmit the collected images to the computer in real time. Due to the high brightness characteristic of the laser, the computer obtains a spot image with a gray value much larger than the background. The moving range of the light spot in the image is segmented into the region of interest of the image. Using color conversion, the color image is converted into a grayscale image, and the grayscale image is rotated and filtered. Comparing with the position of the slide table 24, the relationship between the pixel position of the light spot and the actual displacement of the slide table 24 is solved, and the preliminary positioning of the red light spot position is realized.

[0030] As Figure 1 and Figure 2 shown, a zero position proximity switch 4 is installed between the slide table 24 and the limit end block 22. The zero position proximity switch 4 is used to detect the distance between the slide table 24 and it, and then calculate the distance between the shield tail gaps; a proximity switch is installed at the zero point of the slide table 24; the stroke of the slide table 24 is 150 mm, and the reciprocating direction of the slide table 24 is the direction of the tail shield diameter. When starting and stopping the encoder stepper motor 25, there is acceleration and deceleration control to reduce vibration during starting and stopping, so that the slide table 24 runs smoothly. The slide table 24 leaves the zero position proximity switch 4 at a low speed, and the falling edge of the induction signal is used as the zero point of the slide table 24 to improve the zero point positioning accuracy and eliminate the error caused by the possible loss of steps of the encoder stepper motor 25 during reciprocation, so that the repeat positioning accuracy of the slide table 24 can reach ±0.05 mm.

[0031] As Figure 1 shown, the adjusting rod 26 is a telescopic rod. The adjusting rod 26 is set as a telescopic rod to adjust the lateral distance of the dot laser 28, thereby realizing the adaptation of the entire measuring device to different shield machines.

[0032] The overall working process is as follows: The staff controls the dot laser 28 to irradiate towards the segment direction. Initial calibration is carried out before the shield machine propulsion ends and before the segment erection mode. A steel ruler is attached to the end face of the segment so that the steel ruler receives the dot laser emitted by the dot laser 28. The dot light spot is adjusted to a light spot with a size of 2 - 4 mm, and the position of the light spot on the steel ruler is observed. The adjustable joint 27 is adjusted to make the laser beam parallel to the tail shield shell. The height of the slide table 24 is moved, and calibration is repeated. After meeting the requirements, the adjustable joint 27 is locked;

[0033] The camera 3 collects images of the light spots on the end face of the segment and transmits the collected images to the computer in real time. Due to the high brightness characteristic of the laser, the computer obtains a spot image with a gray value much larger than the background. The moving range of the spots in the image is segmented into the region of interest of the image. Using color conversion, the color image is converted into a grayscale image, and the grayscale image is rotated and filtered. By comparing with the position of the sliding table 24, the relationship between the pixel position of the light spot and the actual displacement of the sliding table 24 is solved, and the preliminary positioning of the position of the red spot is realized. The red spot matched by gray-scale using color recognition adopts the KNN algorithm, with K = 1, and the Manhattan distance is selected as the distance metric to find the nearest neighbor to determine whether there is a red spot in each image;

[0034] The sliding table 24 starts running from the zero position. Due to the existence of the shield tail gap, no red spot can be found in the image initially. As the stroke of the sliding table 24 increases, when the computer image processing extracts the moment of the red spot, it is the position of the segment edge, and the position value h1 of the sliding table 24 at this time is recorded. h1 is the shield tail gap value obtained indirectly. The sliding table 24 runs back and forth 5 times at the edge position, and the shield tail gap values corresponding to the positions of the sliding table 24 when the red spot appears from none to some each time are obtained, and the average value is solved to reduce the error and improve the accuracy of the finally obtained shield tail gap value.

[0035] Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A visual measurement device for the shield tail clearance of a shield machine, comprising a fixed frame (1), the fixed frame (1) is installed on the shield machine, and is characterized in that, It further includes a measuring mechanism (2), which is installed on the fixed frame (1). The measuring mechanism (2) is used to cooperate with a dot laser (28) and a camera (3) to convert the shield tail clearance value into the position where the sliding table (24) moves, thereby realizing the accurate measurement of the shield tail clearance of the shield machine; The measuring mechanism (2) includes a measuring frame (21), a limit end block (22), a limit rod (23), a sliding table (24), a stepping motor with an encoder (25), an adjusting rod (26), an adjustable joint (27) and a dot laser (28). The measuring frame (21) is fixedly installed on the fixed frame (1). Limit end blocks (22) are installed on both sides of the measuring frame (21). A limit rod (23) is installed between the limit end blocks (22). A sliding table (24) is installed on the limit rod (23). A stepping motor with an encoder (25) is installed on one side of the limit end block (22). An adjusting rod (26) is installed on the sliding table (24). An adjustable joint (27) is installed on the adjusting rod (26). A dot laser (28) is installed on the adjustable joint (27).

2. The visual measurement device for the shield tail clearance of a shield machine according to claim 1, characterized in that: The adjustable joint (27) includes a clamping block (271), a fixing bolt (272), an adjusting piece (273) and a clamping plate (274). The clamping blocks (271) are symmetrically installed at the ends of the adjusting rod (26), and fixing holes (2711) are formed in the clamping blocks (271). The fixing bolt (272) is fixed through the fixing hole (2711). An adjusting piece (273) is installed at the other end of the clamping block (271). A clamping plate (274) is installed on the adjusting piece (273).

3. The visual measurement device for the shield tail clearance of a shield machine according to claim 2, characterized in that: A camera (3) is installed on the measuring mechanism (2).

4. The visual measurement device for the shield tail clearance of a shield machine according to claim 3, characterized in that: A zero position proximity switch (4) is installed between the sliding table (24) and the limit end block (22).

5. The visual measurement device for the shield tail clearance of a shield machine according to claim 4, characterized in that: The adjusting rod (26) is a telescopic rod.

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