CN-120684974-B - Pre-splicing-free large steel truss segment assembly multi-mesh real-time digital monitoring method and system

CN120684974BCN 120684974 BCN120684974 BCN 120684974BCN-120684974-B

Abstract

The invention discloses a method and a system for multi-mesh real-time digital monitoring of assembly of large-scale steel truss sections without pre-assembly, belongs to the technical field of bridge construction monitoring, and solves the problems that when the existing method is used for assembly and positioning of steel pipe sections by utilizing an optical prism method, multi-point simultaneous measurement cannot be realized and real-time feedback cannot be realized; the invention provides a preassembled large steel truss segment assembly multi-view real-time digital monitoring method, which adopts a plurality of visual measurements to avoid sight shielding of unidirectional measurement, avoids time waste caused by repeated conversion of a measuring station, can accurately control the end centroid of a steel pipe to avoid uncertain errors caused by measuring a single waist line of the steel pipe, adopts a priori measurement recording method to only measure 3 identification points of a main pipe body in a formal assembly stage, and greatly improves the efficiency of measurement paying-off.

Inventors

WANG SHAORUI
CHEN ZHENG
Cheng Chongcheng
WANG ZHONGJU
WANG XIANG
ZHAN WEI
GUO XIN
NI HONG
ZHOU MI
SU YANG
YANG LIGUI
WANG ZHEN

Assignees

重庆交通大学
四川路桥桥梁工程有限责任公司
四川省交通建设集团有限责任公司
中交第二公路工程局有限公司
重庆建维数智科技有限责任公司

Dates

Publication Date: 20260508
Application Date: 20250623

Claims (7)

1. The method for multi-mesh real-time digital monitoring of the assembly of the large steel truss sections without pre-assembly is characterized by comprising the following steps: S10, segment main pipe blanking scanning, namely scanning segment main pipe blanking based on an industrial camera arranged in a segment main pipe blanking field, and completing local coordinate conversion of the centroids of two ends of the main pipe in a pipe body target coordinate system; s20, segment main pipe paying-off monitoring, namely arranging a camera system in a main pipe assembling field, calibrating an industrial camera, and resolving world coordinates of the centroids at two ends of a main pipe in the main pipe assembling field; S30, calculating the centroids of two ends of the main pipe, adjusting the pose of the main pipe and the flange plate based on the calculation result, monitoring the pose error in real time, and correcting the assembly of the main pipe based on the pose error; s40, paying off and fixing the flange, namely measuring world coordinates of the identification points of the flange, resolving, adjusting the pose of the flange based on the resolving result, and welding the adjusted flange; the segment main pipe blanking scanning comprises the following steps: s101, arranging and calibrating a 4-industry camera system of a blanking field, and scanning the blanking of a segment main pipe based on an industry camera arranged on the blanking length of the segment main pipe; s102, measuring world coordinates of an ith main pipe body and a pipe end mark point; s103, world coordinates of the ith main pipe body and the pipe end mark points are obtained, and world coordinates of the centroids at the two ends of the main pipe are calculated; S104, loading world coordinates of the centroids at the two ends of the main pipe, and carrying out local coordinate conversion of the centroids at the two ends of the main pipe in a pipe body target coordinate system; the segment is responsible for pay-off monitoring, including: s201, arranging and calibrating a camera system of the assembled field 6, arranging the camera system in a main assembled field and calibrating an industrial camera, wherein the calibration of the industrial camera comprises calibration of an internal reference matrix and external parameter data; s202, after industrial camera erection and calibration, measuring the ith main pipe body target; s203, solving the world coordinates of the centroids at the two ends of the main pipe in the main pipe assembly field by using the inverse transformation.
2. The method for real-time digital monitoring of the preassembled large steel truss segment assembly, as set forth in claim 1, is characterized in that when the 4 industrial camera system of the blanking field is arranged and calibrated, the calibration of the industrial cameras comprises internal reference matrix calibration and external reference matrix calibration, wherein the internal reference matrix calibration adopts a Zhang Zhengyou calibration method, the external reference matrix calibration adopts a normalized eight-point method, after the industrial cameras are erected, at least 3 targets are randomly arranged on different horizontal positions and different heights on the ground in advance, the side length of each target for calibration is not less than 10cm, world coordinates of all target center points are measured and recorded in advance by using a total station, then pixel coordinates of all target center points in a camera imaging plane are quickly and accurately searched by using a YOLO algorithm or a manual stab point, then the external reference matrix of all industrial cameras is obtained by adopting a P3P or PnP algorithm, one of the industrial cameras is defined as a zero-number camera, a rotation matrix R matrix T between the adjacent industrial cameras and the zero-number cameras is constructed by taking the optical center of the zero-number camera as the coordinates, and absolute relation between rotation and translation of the adjacent cameras is obtained, and the absolute origin of the industrial camera is translated.
3. The method for multi-view real-time digital monitoring of the assembly of the large steel truss sections without pre-assembly according to claim 2, wherein when solving the world coordinates of the centroids at the two ends of the main pipe, triangulating pixel points in imaging planes of 4 industrial cameras, obtaining world coordinates of the pipe body and the pipe end marking point of the i-th main pipe through beam adjustment optimization of multiple views, obtaining space circle center coordinates of the end part of the steel pipe according to least square fitting, and fitting the world coordinates of the circle center of the end part of the steel pipe by using the space points of the center of the end reflection sphere.
4. The method for multi-mesh real-time digital monitoring of preassembled large steel truss segment assembly of claim 3, wherein when carrying out local coordinate conversion of the centers of two ends of a main pipe in a pipe body target coordinate system, firstly, 3 targets on the outer wall of any ith steel pipe are selected as reference points of the local coordinate system, and a pipe body local coordinate system Coor is established , , ) And then converting world coordinates of circle centers at two ends of the steel pipe into a local coordinate system of the pipe body.
5. The method for multi-mesh real-time digital monitoring of the assembly of the large steel truss sections without pre-assembly according to claim 4, wherein the assembly correction of the main section pipe comprises the following steps: S301, calculating the centroids of two ends of a main pipe; s302, adjusting the pose of the main pipe and the flange plate based on the calculation result, monitoring the pose error in real time, and judging whether the pose error meets the requirement; S303, if the pose error meets the requirement, initially fixing the segment main pipe by spot welding, and if the pose error does not meet the requirement, assembling and rectifying the segment main pipe based on the pose error; S304, finely adjusting the web members and the cross braces, and welding and forming.
6. The method for multi-objective real-time digital monitoring of the assembly of the pre-assembled large steel truss sections, as set forth in claim 5, wherein the flange paying-off and fixing steps include: S401, measuring world coordinates of an identification point of a flange plate of a bolt joint by using a multi-view system formed by calibrated and fixed industrial cameras, and outputting a resolving result in Jie Suanfa blue plate pose; S402, adjusting the pose of the flange plate based on the resolving result, and spot-welding the fixed flange plate; S403, formally welding the flange plates to finish assembly manufacturing of the large-scale steel truss sections.
7. The pre-splicing-free large steel truss segment assembly multi-mesh real-time digital monitoring system is used for implementing the pre-splicing-free large steel truss segment assembly multi-mesh real-time digital monitoring method according to any one of claims 1-6, and is characterized in that the pre-splicing-free large steel truss segment assembly multi-mesh real-time digital monitoring system comprises: the blanking scanning module scans the blanking of the segment main pipe based on an industrial camera arranged in the blanking field of the segment main pipe and completes the local coordinate conversion of the centroids of the two ends of the main pipe in a pipe body target coordinate system; The paying-off monitoring module is used for arranging a camera system in the main pipe assembly field and calibrating an industrial camera, and resolving the world coordinates of the centroids of the two ends of the main pipe in the main pipe assembly field; the assembly correction module is used for calculating the centroids at two ends of the main pipe, adjusting the pose of the main pipe and the flange plate based on the calculation result, monitoring the pose error in real time, and assembling and correcting the segment main pipe based on the pose error; and the paying-off fixing module is used for measuring world coordinates of the identification points of the flange plate, resolving, adjusting the pose of the flange plate based on the resolving result and welding the adjusted flange plate.

Description

Pre-splicing-free large steel truss segment assembly multi-mesh real-time digital monitoring method and system Technical Field The invention belongs to the technical field of bridge construction monitoring, and particularly relates to a method and a system for multi-view real-time digital monitoring of assembly of large-scale steel truss sections without pre-assembly. Background Construction of ultra-large steel structures generally depends on multi-section assembly, such as main arches of a large-span steel pipe concrete arch bridge, a stiff skeleton arch bridge, a steel box arch bridge and the like, and steel truss section assembly manufacturing of the ultra-large steel structures depends on a physical pre-assembly technology. The technology adopts the geometric form of the preface section to assist the positioning and paying-off of the rod pieces of the follow-up section, and has the problem of great consumption of land, facilities, personnel, consumables and the like. On the one hand, in order to ensure smoothness of the main arch line shape after splicing and alignment of the hole positions of connecting bolts between adjacent main arch sections, in the prior art, when the current section is positioned, the adjacent splicing sections of the preamble are adopted to be placed in a preset position in advance, the current section is utilized to carry out physical auxiliary positioning, and the preamble section is provided with a plurality of sections, namely an n+1 mode. The manufacturing method occupies a long and narrow field exceeding hundred meters, occupies extremely large land resources, is extremely difficult to realize large-field processing even in a mountain area high-steep complex and difficult terrain environment, and requires an additional steel working platform to be erected. On the other hand, because the steel pipe rod piece of the segment adopts a pipe side waist line measuring method when positioning and paying off, the measuring process needs to be adjusted repeatedly, and finally the rod piece is fixed through a jig frame, the method has poor estimation precision on the actual centroid and the central axis of the steel pipe and low positioning efficiency, in addition, if the welding and positioning of the subsequent segment are limited by the field, the leading segment is required to be strung, and the position is required to be additionally measured and adjusted when the subsequent segment is moved again, so that the work efficiency is reduced. In general, the problems of low turnover rate of auxiliary workpieces, long time consumption for repeated adjustment, high personnel quality requirement and the like caused by integral pre-splicing of a large number of multi-sections severely restrict the efficiency of the main arch assembly, processing and forming. Therefore, if the single-section manufacturing of the large main arch steel truss section can be realized, the process of adjusting the preamble section can be omitted, the occupation of land resources and the investment of a large amount of personnel and equipment can be greatly reduced, and the difficult problem of difficult assembly manufacturing under the condition of complex mountain terrain can be solved. However, the single-section independent manufacture of the large steel truss sections has extremely high requirements on the positioning precision of the axis of the rod, so that the smoothness of the axis is ensured, and the hole positions of the connecting bolts are ensured to be aligned all at once without the assistance of adjacent sections. The number of the common inner flange splicing bolt holes of the segments is 24-32, and under the large scale that the pipe diameter exceeds 1m and the inter-pipe distance exceeds 10m, the millimeter-level space positioning precision (+ -1 mm) of each bolt hole is ensured, the space position and the gesture of the flange plate are strictly controlled, and the accurate centering of the circle center of the chord steel pipe is the premise of the independent manufacturing of the main arch segment. Besides the requirement of positioning accuracy, whether quick positioning can be realized is also a key for improving the manufacturing efficiency of the main arch. The prior measuring technology can not simultaneously meet the dual guarantee of millimeter-level paying-off positioning, deviation rectifying and adjusting instantaneity. The traditional optical prism measurement cannot accurately position the pipe orifice center, the total station, the level gauge and other instruments are low in station transferring efficiency, the industrial manufacturing three-dimensional reconstruction technology based on structured light is small in field of view range and cannot be expanded to large-scale workpiece processing, the technology of three-dimensional image reconstruction is sensitive to environment light intensity, robustness and efficiency are low, the three-dimensional laser scanning technology