Tower foot node attitude determination method and system based on laser positioning

Abstract

The invention discloses a tower foot node attitude determination method and system based on laser positioning. The method comprises the steps that targets are installed at the limited number of non-coplanar positioning circular rings on a node plate; laser scanning equipment is used for collecting node plate surface point cloud information, and target information is recognized from the point cloud information; the method also includes determining a centroid position as a source point cloud based on the target information; taking corresponding centroid position information in the tower foot digital model as a target point cloud, and calculating a position conversion matrix as a tower foot node attitude matrix by using a point cloud registration algorithm in combination with the source point cloud, wherein the tower foot digital model is a tower foot node refined three-dimensional model generated through software, and the position of a positioning circular ring in the tower foot digital model is the same as the position of a positioning circular ring on a node plate. According to the invention, the position information of the key points on the tower foot nodes of the power transmission tower is adopted, the node space attitude matrix is calculated through point cloud registration, and compared with a manual ruler measurement or laser point cloud three-dimensional reconstruction method, the precision and efficiency are improved, and non-convergence of solving is avoided.

Description

technical field [0001] The invention relates to the field of processing steel pipe transmission towers, in particular to a method and system for determining the posture of tower foot nodes based on laser positioning. Background technique [0002] The tower foot node of the transmission tower is composed of multiple steel plates, which need to be welded together to form a whole to transmit the axial force of the main material and the oblique material to the foundation of the transmission tower. For a long time, the tower feet of transmission towers have been manually welded. At present, with the rapid development of information technology, advanced numerical control equipment such as welding robot arms has begun to replace manual welding. When relying on robot arms and other advanced numerical control equipment to weld the tower foot nodes of transmission towers, it is generally necessary to use spot welding to connect the joint plates on the tower foot nodes as a whole; the...

AI Technical Summary

Problems solved by technology

[0003] At present, the posture of nodes is determined mainly by manual work and various rulers, which is not only a heavy workload, but also inaccurate; some people have also proposed a method of using laser scanning nodes and performing 3D reconstruction to determine the posture of nodes

However, this method has the following two disadvantages: 1) The scanning and data processing time is long, which affects the welding efficiency

When performing operations such as laser point cloud registration and recognition, the calculation time is proportional to the square of the number of data points. Considering that the number of data points in the laser point cloud is generally more than 5000, the computer processing time using this method will be within one hour. The above seriously affects the welding efficiency; 2) At present, the laser point cloud registration algorithm is an iterative algorithm, and there is no analytical solution, which causes its iteration to often fail, and there is a high probability that it cannot converge to an accurate solution, resulting in a solution failure.

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