RGB-D visual segment grabbing and recognition system, assembly positioning system and assembly positioning method

Abstract

The present invention relates to an RGB-D visual segment grabbing and identifying system, an assembly positioning system and an assembly positioning method, wherein the visual segment grabbing and identifying is the point cloud data of the segment surface photographed by an RGB-D camera, outliers are removed by filtering and noise interference is reduced, and then the background point cloud is removed by point cloud segmentation to obtain the segment point cloud; the point cloud of the template segment and the segment to be grabbed are aligned by point cloud smoothing and normal estimation, the recognition and posture estimation of the segment to be grabbed are completed, and the assembler is guided to grab the segment to be grabbed; the segment assembly positioning is to move the segment to the target position by pre-calculating the rough positioning after the segment is grabbed, and then the corresponding assembly method is designed for different types of segments to achieve the precise positioning and assembly of the segment, and complete the assembly of the whole ring of segments. The present invention can realize the rapid identification and assembly of the segment, and the assembly positioning has good stability and high accuracy.

Description

Technical Field

[0001] The present invention relates to the field of mechanical engineering technology, and in particular to an RGB-D visual tube segment grabbing and identifying system, an assembly positioning system and an assembly positioning method. Background Art

[0002] At present, shield machines play an important role in the construction of subway tunnels, highway tunnels, railway tunnels, river crossing tunnels and various urban municipal tunnel projects. The degree of automation of shield machines plays a vital role in construction efficiency, labor costs and safety.

[0003] The segment assembly machine is an important part of the shield machine. Its function is to support and protect the tunnel dug by the shield machine with pre-made concrete segments to prevent the impact of surface settlement and groundwater infiltration on the tunnel and improve the safety of the tunnel. The segment assembly speed directly affects the tunneling speed of the entire shield machine. At present, domestic shield machines mainly rely on manual work to complete the rotation and lifting of segments and segment assembly in tunnel construction. The assembly efficiency is low, and a large amount of manpower is required, and the safety is not high.

[0004] Therefore, how to automatically identify the segment type, segment position and three-dimensional coordinates without human intervention, and guide the assembly machine to automatically grab and assemble the segments to improve work efficiency is a technical problem that needs to be urgently solved by technical personnel in this field. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies in the prior art and provide an RGB-D vision segment grabbing and identification system, an assembly positioning system and an assembly positioning method. The present invention uses RGB-D vision to determine the segment type and obtain the segment position and posture, completes the guidance of segment grabbing, and completes the assembly of the segment by extracting calculations and RGB to identify the segment bolt holes and edges.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] An RGB-D visual pipe segment grabbing and recognition system, the system comprises a front 3D visual module and a data processing terminal installed on an assembly machine; the front 3D visual module is installed in front of the upper surface of the grabbing platform;

[0008] The data processing terminal is connected to the front 3D vision module; in the pipe segment grabbing stage, the data processing terminal receives the point cloud data of the pipe segment surface taken by the RGB-D camera, removes outliers and reduces noise interference through filtering, and then removes the background point cloud through point cloud segmentation to obtain the pipe segment point cloud; the point cloud of the template pipe segment and the pipe segment to be grabbed are aligned through point cloud smoothing and normal estimation, the recognition and posture estimation of the pipe segment to be grabbed are completed, and the assembly machine is guided to grab the pipe segment to be grabbed.

[0009] Furthermore, the front 3D vision module includes an RGB-D camera and a light source, and the RGB-D camera is used to capture point cloud data of the surface of the pipe segment.

[0010] A pipe segment assembly positioning system, the system comprises a front 3D vision module, a left RGB vision module, a right RGB vision module and a data processing terminal installed on an assembly machine; the front 3D vision module is installed in front of the upper surface of a grabbing platform; the left RGB vision module and the right RGB vision module are installed on the left and right sides of the upper surface of the grabbing platform respectively;

[0011] The data processing terminal is connected to the front 3D vision module, the left RGB vision module, and the right RGB vision module; in the segment grabbing stage, the data processing terminal receives the point cloud data of the segment surface taken by the RGB-D camera, removes outliers and reduces noise interference through filtering, and then removes the background point cloud through point cloud segmentation to obtain the segment point cloud; the point cloud of the template segment and the segment to be grabbed are aligned through point cloud smoothing and normal estimation, the segment to be grabbed is identified and the posture is estimated, and the assembly machine is guided to grab the segment to be grabbed;

[0012] In the assembly rough positioning stage, the data processing terminal guides the assembling machine to move the segment to be grasped to the assembly rough positioning position according to the position and type of the segment to be grasped and the pre-calculated segment assembly position;

[0013] During the precise positioning stage of assembly, the data processing terminal turns on the front 3D vision module, the left RGB vision module or the right RGB vision module according to the type of the pipe segment to be grabbed, identifies the bolt holes and / or edges of the pipe segment to be assembled, and guides the pipe segment to be assembled to align with the assembled pipe segment.

[0014] Furthermore, the front 3D vision module, the left RGB vision module, and the right RGB vision module each include an RGB-D camera and a light source, and the RGB-D camera is used to capture point cloud data of the surface of the pipe segment.

[0015] Furthermore, the assembling machine includes a walking beam, a lifting cylinder, a slewing mechanism, a rotating frame, a grabbing platform, a slag conveyor belt and a translation cylinder; the rotating frame is installed on the walking beam, the slewing mechanism is installed behind the rotating frame, the two lifting cylinders are respectively installed on both sides of the slewing mechanism, the grabbing platform is fixed to the two lifting cylinders through a yoke, the slag conveyor belt is installed in the middle of the walking beam, and the translation cylinder is installed on the walking beam and located on the inner side of the rotating frame to realize the overall translation of the lifting cylinder; the lifting cylinder is used to lift the grabbing platform, and the slewing mechanism is used to realize the rotation of the lifting cylinder and the grabbing platform.

[0016] A segment assembly positioning method based on a segment assembly positioning system, the method comprising the following steps:

[0017] Step 1: By grabbing the segment posture and type and the pre-calculated segment assembly position, the assembly machine moves the segment to the assembly rough positioning position;

[0018] Step 2: When assembling the first standard piece of the current ring, turn on the front 3D vision module, the left RGB vision module and the right RGB vision module. If the following three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0019] Condition 1: Use the front 3D vision module and the RGB-D camera to identify the long side of the segment to be assembled and the long side of the segment that has been assembled in the previous ring, and calculate the distance between the two sides. When the distance is less than or equal to the set threshold, it is determined to be aligned with the segment in the previous ring of the segment to be assembled;

[0020] Condition 2: Using the left RGB vision module, by identifying the two bolt holes on the left side of the segment to be assembled and the bolt holes on the left side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined to be aligned with the previous segment of the segment to be assembled;

[0021] Condition 3: Using the right RGB vision module, by identifying the two bolt holes on the right side of the segment to be assembled and the bolt holes on the right side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined to be aligned with the previous segment of the segment to be assembled;

[0022] Step 3: When assembling the second standard piece or the first adjacent piece of the current ring, turn on the front 3D vision module and the right RGB vision module. When the following three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0023] Condition 1: Use the front 3D vision module and the RGB-D camera to identify the long side of the segment to be assembled and the long side of the segment that has been assembled in the previous ring, and calculate the distance between the two sides. When the distance is less than or equal to the set threshold, it is determined to be aligned with the segment in the previous ring of the segment to be assembled;

[0024] Condition 2: Using the right RGB visual module, by identifying the two bolt holes on the left side of the assembled segment on the right side of the segment to be assembled and the two bolt holes on the right side of the segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that it is aligned with the assembled segment on the right side of the segment to be assembled;

[0025] Condition 3: Using the right RGB vision module, by identifying the left side of the assembled segment on the right side of the segment to be assembled and the right side of the segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled segment on the right side of the segment to be assembled;

[0026] Step 4: When assembling the third standard piece or the second connecting piece of the current ring, turn on the front 3D vision module and the left RGB vision module. When the following three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0027] Condition 1: Use the front 3D vision module and the RGB-D camera to identify the long side of the segment to be assembled and the long side of the segment that has been assembled in the previous ring, and calculate the distance between the two sides. When the distance is less than or equal to the set threshold, it is determined to be aligned with the segment in the previous ring of the segment to be assembled;

[0028] Condition 2: Using the left RGB visual module, by identifying the two bolt holes on the right side of the assembled segment on the left side of the segment to be assembled and the two bolt holes on the left side of the segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that it is aligned with the assembled segment on the left side of the segment to be assembled;

[0029] Condition 3: Using the left RGB visual module, by identifying the right side of the assembled segment on the left side of the segment to be assembled and the left side of the segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled segment on the left side of the segment to be assembled;

[0030] Step 5: When assembling the current ring capping piece, turn on the front 3D vision module, the left RGB vision module and the right RGB vision module. When all three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0031] Condition 1: Use the front 3D vision module and the RGB-D camera to identify the long edge of the assembled segment and the edge of the segment to be assembled next to it, and calculate the distance between them. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous segment of the segment to be assembled;

[0032] Condition 2: Using the left RGB visual module, by identifying the right side of the assembled segment on the left side of the segment to be assembled and the left side of the segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled segment on the left side of the segment to be assembled;

[0033] Condition 3: Using the right RGB vision module, by identifying the left side of the assembled segment on the right side of the segment to be assembled and the right side of the segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled segment on the right side of the segment to be assembled;

[0034] Step 6: Complete the assembly of the entire ring of segments.

[0035] The beneficial effects of the present invention are as follows:

[0036] (1) The pipe segment grasping and identification system of the present invention adopts a 3D vision module, which has stronger anti-interference ability and higher accuracy in posture acquisition, avoiding the influence of light intensity on the recognition and positioning results, ensuring more efficient and accurate recognition and positioning results, thereby achieving more accurate grasping.

[0037] (2) The assembly positioning system and assembly positioning method of the present invention adopt RGB modules at different positions for different types of pipe segments, so that each type of pipe segment can be accurately assembled, and each ring of pipe segments can be quickly assembled with good stability and high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the segment assembly positioning system of the present invention Figure 1 .

[0039] Figure 2 Schematic diagram of the segment assembly positioning system of the present invention Figure 2 .

[0040] Figure 3 Schematic diagram of three visual modules.

[0041] Figure 4 Flowchart for segment capture for the data processing terminal.

[0042] Figure 5 The present invention is a flow chart of the segment assembly positioning method.

[0043] Figure 6 This is a schematic diagram for assembling the first standard piece.

[0044] Figure 7 It is a schematic diagram of assembling the second standard piece or the first collar piece; wherein Figure (1) is a schematic diagram of assembling the second standard piece, and Figure (2) is a schematic diagram of assembling the first collar piece.

[0045] Figure 8 It is a schematic diagram of assembling the third standard piece or the second collar piece. Figure (1) is a schematic diagram of assembling the third standard piece, and Figure (2) is a schematic diagram of assembling the second collar piece.

[0046] Fig. 9 This is a schematic diagram of assembling the roof piece.

[0047] Figures 1 to 3Middle: assembling machine 1, front 3D vision module 2, left RGB vision module 3, right RGB vision module 4, walking beam 11, lifting cylinder 12, slewing mechanism 13, rotating frame 14, grabbing platform 15, slag conveyor belt 16, front RGB-D camera 21, front light source 22, left RGB camera 31, left light source 32, right RGB camera 41, right light source 42. DETAILED DESCRIPTION

[0048] The present invention will be described in detail below based on the accompanying drawings and preferred embodiments, and the purpose and effects of the present invention will become more clear. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0049] The RGB-D vision-based tube piece grasping and recognition system of the present invention comprises a front 3D vision module and a data processing terminal on the assembling machine 1; the front 3D vision module is installed in front of the upper surface of the grasping platform;

[0050] like Figure 1 and 2 As shown, the assembling machine 1 includes a walking beam 11, a lifting cylinder 12, a slewing mechanism 13, a rotating frame 14, a grabbing platform 15, a slag conveyor belt 16 and a translation cylinder; the rotating frame 14 is installed on the walking beam 11, the slewing mechanism 13 is installed behind the rotating frame 14, the two lifting cylinders 12 are respectively installed on both sides of the slewing mechanism 13, the grabbing platform 15 is fixed on the two lifting cylinders 12 through a yoke, the slag conveyor belt 16 is installed in the middle of the walking beam 11, and the translation cylinder is installed on the walking beam 11 and is located on the inner side of the rotating frame 14, which is used to realize the overall translation of the lifting cylinder 12; the lifting cylinder 12 is used to lift the grabbing platform 15, and the slewing mechanism 13 is used to realize the rotation of the lifting cylinder 12 and the grabbing platform 15.

[0051] like Figure 3 As shown, the front 3D vision module 2 includes a front RGB-D camera 21 and a light source 22.

[0052] like Figure 4 As shown, the data processing terminal is connected to the front 3D vision module; in the segment grabbing stage, the data processing terminal receives the point cloud data of the segment surface taken by the RGB-D camera, removes outliers and reduces noise interference through filtering, and then removes the background point cloud through point cloud segmentation to obtain the segment point cloud; the point cloud of the template segment and the segment to be grabbed are aligned through point cloud smoothing and normal estimation, the segment to be grabbed is identified and the posture is estimated, and the assembly machine is guided to grab the segment to be grabbed.

[0053] On the basis of the pipe segment grabbing and identification system, the left RGB vision module and the right RGB vision module are added, and the positioning function of the data processing terminal is added to form a pipe segment assembly positioning system. Figure 2 As shown, the segment assembly positioning system includes a front 3D vision module 2, a left RGB vision module 3, a right RGB vision module 4 and a data processing terminal installed on the assembly machine 1; the front 3D vision module 2 is installed in front of the upper surface of the grabbing platform 15; the left RGB vision module 3 and the right RGB vision module 4 are installed on the left and right sides of the upper surface of the grabbing platform 15 respectively. Figure 3 As shown, the left RGB visual module 3 includes a left RGB camera 31 and a left light source 32, and the right RGB visual module 4 includes a right RGB camera 41 and a right light source 42. The assembling machine 1 realizes the assembly of the pipe segments by translation, lifting and rotation.

[0054] The present invention uses the front 3D vision module 2, the left RGB vision module 3 and the right RGB vision module 4 to identify the pipe segments and obtain the pipe segment posture and precise positioning of the pipe segments, thereby providing guidance for the grabbing and assembly of the assembler, completing the grabbing and assembly of the pipe segments with high speed, good stability and high accuracy.

[0055] The data processing terminal is connected to the front 3D vision module 2, the left RGB vision module 3, and the right RGB vision module 4; in the segment grabbing stage, the data processing terminal receives the point cloud data of the segment surface taken by the RGB-D camera, removes outliers and reduces noise interference through filtering, and then removes the background point cloud through point cloud segmentation to obtain the segment point cloud; the point cloud of the template segment and the segment to be grabbed are aligned through point cloud smoothing and normal estimation, the segment to be grabbed is identified and the posture is estimated, and the assembly machine 1 is guided to grab the segment to be grabbed;

[0056] In the assembly rough positioning stage, the data processing terminal guides the assembling machine 1 to move the segment to be grasped to the assembly rough positioning position according to the position and type of the segment to be grasped and the pre-calculated segment assembly position;

[0057] During the precise positioning stage of assembly, the data processing terminal turns on the front 3D vision module, the left RGB vision module or the right RGB vision module according to the type of the pipe segment to be grabbed, identifies the bolt holes and / or edges of the pipe segment to be assembled, and guides the pipe segment to be assembled to align with the assembled pipe segment.

[0058] like Figures 5 to 9 As shown, the segment assembly positioning method based on the segment assembly positioning system includes the following steps:

[0059] Step 1: by grasping the segment posture and type and the segment assembly position calculated in advance, the assembly machine 1 moves the segment to the assembly rough positioning position;

[0060] Step 2: When assembling the first standard piece of the current ring, turn on the front 3D vision module 2, the left RGB vision module 3 and the right RGB vision module 4. If the following three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0061] Condition 1: Use the front 3D vision module 2 to identify the long side of the segment to be assembled and the long side of the segment assembled in the previous ring through the RGB-D camera, calculate the distance between the two sides, and when the distance is less than or equal to the set threshold, it is determined to be aligned with the segment in the previous ring of the segment to be assembled;

[0062] Condition 2: Using the left RGB visual module 3, by identifying the two bolt holes on the left side of the segment to be assembled and the bolt holes on the left side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined to be aligned with the previous segment of the segment to be assembled;

[0063] Condition 3: Using the right RGB visual module 4, by identifying the two bolt holes on the right side of the segment to be assembled and the bolt holes on the right side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined that the segment is aligned with the previous segment of the segment to be assembled;

[0064] Step 3: When assembling the second standard piece or the first adjacent piece of the current ring, the front 3D vision module 2 and the right RGB vision module 4 are turned on, and the current pipe segment assembly is determined to be complete when the following three conditions are met at the same time;

[0065] Condition 1: Use the front 3D vision module 2 to identify the long side of the segment to be assembled and the long side of the segment assembled in the previous ring through the RGB-D camera, calculate the distance between the two sides, and when the distance is less than or equal to the set threshold, it is determined to be aligned with the segment in the previous ring of the segment to be assembled;

[0066] Condition 2: Using the right RGB visual module 4, by identifying the two bolt holes on the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the two bolt holes on the right side of the pipe segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that the pipe segment to be assembled is aligned with the assembled pipe segment on the right side of the pipe segment to be assembled;

[0067] Condition 3: using the right RGB visual module 4, by identifying the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the right side of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled pipe segment on the right side of the pipe segment to be assembled;

[0068] Step 4: When assembling the third standard piece or the second connecting piece of the current ring, turn on the front 3D vision module 2 and the left RGB vision module 3. When the following three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0069] Condition 1: Use the front 3D vision module 2 to identify the long side of the segment to be assembled and the long side of the segment that has been assembled in the previous ring through the RGB-D camera, calculate the distance between the two sides, and when the distance is less than or equal to the set threshold, it is determined to be aligned with the segment of the previous ring of the segment to be assembled;

[0070] Condition 2: Using the left RGB visual module 3, by identifying the two bolt holes on the right side of the assembled segment on the left side of the segment to be assembled and the two bolt holes on the left side of the segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that it is aligned with the assembled segment on the left side of the segment to be assembled;

[0071] Condition 3: Using the left RGB visual module 3, by identifying the right side of the assembled pipe segment on the left side of the pipe segment to be assembled and the left side of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled pipe segment on the left side of the pipe segment to be assembled;

[0072] Step 5: When assembling the current ring capping piece, the front 3D vision module 2, the left RGB vision module 3 and the right RGB vision module 4 are turned on. When all three conditions are met at the same time, it is determined that the current pipe segment is assembled;

[0073] Condition 1: Use the front 3D vision module 2 to identify the long edge of the assembled segment and the edge of the segment to be assembled close to it through the RGB-D camera, and calculate the distance between the two. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous ring of segments to be assembled;

[0074] Condition 2: Using the left RGB visual module 3, by identifying the right side of the assembled segment on the left side of the segment to be assembled and the left side of the segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled segment on the left side of the segment to be assembled;

[0075] Condition 3: using the right RGB visual module 4, by identifying the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the right side of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the assembled pipe segment on the right side of the pipe segment to be assembled;

[0076] Step 6: Complete the assembly of the entire ring of segments.

[0077] Those skilled in the art can understand that the above are only preferred examples of the invention and are not intended to limit the invention. Although the invention is described in detail with reference to the above examples, those skilled in the art can still modify the technical solutions recorded in the above examples or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, etc. made within the spirit and principle of the invention shall be included in the protection scope of the invention.

Claims

1. A segment assembly positioning method based on a segment assembly positioning system, It is characterized in that The pipe segment assembly positioning system comprises a front 3D vision module, a left RGB vision module, a right RGB vision module and a data processing terminal installed on an assembly machine (1); the front 3D vision module is installed in front of the upper surface of a gripping platform (15); the left RGB vision module (3) and the right RGB vision module (4) are installed on the left and right sides of the upper surface of the gripping platform (15), respectively; The data processing terminal is connected to the front 3D vision module, the left RGB vision module, and the right RGB vision module; in the segment grabbing stage, the data processing terminal receives the point cloud data of the segment surface photographed by the RGB-D camera, removes outliers and reduces noise interference by filtering, and then removes the background point cloud by point cloud segmentation to obtain the segment point cloud; the point cloud of the template segment and the segment to be grabbed are aligned by point cloud smoothing and normal estimation, the segment to be grabbed is identified and the posture is estimated, and the assembly machine (1) is guided to grab the segment to be grabbed; In the assembly rough positioning stage, the data processing terminal guides the assembly machine (1) to move the segment to be grasped to the assembly rough positioning position according to the position and type of the segment to be grasped and the segment assembly position calculated in advance; In the assembly precision positioning stage, the data processing terminal activates the front 3D vision module, the left RGB vision module or the right RGB vision module according to the type of the segment to be grabbed, identifies the bolt holes and / or edges of the segment to be assembled, and guides the segment to be assembled to align with the assembled segment; The segment assembly positioning method includes the following steps: Step 1: by grasping the segment posture and type and the segment assembly position calculated in advance, the assembly machine (1) moves the segment to the assembly rough positioning position; Step 2: When assembling the first standard piece of the current ring, the front 3D vision module (2), the left RGB vision module (3) and the right RGB vision module (4) are turned on. If the following three conditions are met at the same time, it is determined that the current pipe segment is assembled; Condition 1: Using the front 3D vision module (2) and the RGB-D camera, the long side of the segment to be assembled and the long side of the previously assembled segment are identified, and the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous segment of the segment to be assembled; Condition 2: Using the left RGB vision module (3), by identifying the two bolt holes on the left side of the segment to be assembled and the bolt holes on the left side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined that the segment is aligned with the previous segment of the segment to be assembled; Condition 3: Using the right RGB vision module (4), by identifying the two bolt holes on the right side of the segment to be assembled and the bolt holes on the right side of the previously assembled segment, if the center points of the three holes are in a straight line, it is determined that the segment is aligned with the previous segment of the segment to be assembled; Step 3: When assembling the second standard piece or the first adjacent piece of the current ring, the front 3D vision module (2) and the right RGB vision module (4) are turned on, and the current pipe segment assembly is determined to be complete when the following three conditions are met at the same time; Condition 1: Using the front 3D vision module (2) and the RGB-D camera, the long side of the segment to be assembled and the long side of the previously assembled segment are identified, and the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous segment of the segment to be assembled; Condition 2: Using the right RGB vision module (4), by identifying the two bolt holes on the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the two bolt holes on the right side of the pipe segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that the pipe segment is aligned with the assembled pipe segment on the right side of the pipe segment to be assembled; Condition 3: using the right RGB vision module (4), by identifying the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the right side of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined that the assembled pipe segment on the right side of the pipe segment to be assembled is aligned; Step 4: When assembling the third standard piece or the second connecting piece of the current ring, turn on the front 3D vision module (2) and the left RGB vision module (3). When the following three conditions are met at the same time, it is determined that the current pipe segment is assembled; Condition 1: Using the front 3D vision module (2), the RGB-D camera is used to identify the long side of the segment to be assembled and the long side of the previously assembled segment, and the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous segment of the segment to be assembled; Condition 2: Using the left RGB visual module (3), by identifying the two bolt holes on the right side of the assembled pipe segment on the left side of the pipe segment to be assembled and the two bolt holes on the left side of the pipe segment to be assembled, if the four corners of the quadrilateral formed by the center points of the four holes are all right angles, it is determined that the pipe segment is aligned with the assembled pipe segment on the left side of the pipe segment to be assembled; Condition 3: Using the left RGB vision module (3), by identifying the right side edge of the assembled pipe segment on the left side of the pipe segment to be assembled and the left side edge of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined that the assembled pipe segment on the left side of the pipe segment to be assembled is aligned; Step 5: When assembling the current ring capping piece, the front 3D vision module (2), the left RGB vision module (3) and the right RGB vision module (4) are turned on. When all three conditions are met at the same time, it is determined that the current pipe segment is assembled; Condition 1: Using the front 3D vision module (2), the RGB-D camera is used to identify the long edge of the assembled segment and the edge of the segment to be assembled near it, and the distance between the two is calculated. When the distance is less than or equal to the set threshold, it is determined to be aligned with the previous ring of segments on the segment to be assembled; Condition 2: Using the left RGB visual module (3), by identifying the right side edge of the assembled pipe segment on the left side of the pipe segment to be assembled and the left side edge of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined that the assembled pipe segment on the left side of the pipe segment to be assembled is aligned; Condition 3: using the right RGB vision module (4), by identifying the left side of the assembled pipe segment on the right side of the pipe segment to be assembled and the right side of the pipe segment to be assembled, the distance between the two sides is calculated. When the distance is less than or equal to the set threshold, it is determined that the assembled pipe segment on the right side of the pipe segment to be assembled is aligned; Step 6: Complete the assembly of the entire ring of segments.

2. The segment assembly and positioning method according to claim 1, It is characterized in that The front 3D vision module, the left RGB vision module, and the right RGB vision module each comprise an RGB-D camera (21) and a light source (22), wherein the RGB-D camera (21) is used to capture point cloud data of the surface of the pipe segment.

3. The segment assembly and positioning method according to claim 1, It is characterized in that The assembling machine (1) comprises a walking beam (11), a lifting cylinder (12), a slewing mechanism (13), a rotating frame (14), a grabbing platform (15), a slag conveyor belt (16) and a translation cylinder; the rotating frame (14) is mounted on the walking beam (11), the slewing mechanism (13) is mounted behind the rotating frame (14), two lifting cylinders (12) are respectively mounted on both sides of the slewing mechanism (13), the grabbing platform (15) is fixed to the two lifting cylinders (12) through a yoke, the slag conveyor belt (16) is mounted in the middle of the walking beam (11), and the translation cylinder is mounted on the walking beam (11) and located on the inner side of the rotating frame (14) to realize the overall translation of the lifting cylinder (12); the lifting cylinder (12) is used to lift the grabbing platform (15), and the slewing mechanism (13) is used to realize the rotation of the lifting cylinder (12) and the grabbing platform (15).

Images