Visual measurement and 3D reconstruction method of model terrain in muddy water

Abstract

The invention provides a method for visual measurement and three-dimensional reconstruction of model terrain in muddy water. First, a B-ultrasound instrument is used to directly obtain a video image file of an underwater model terrain and a single-frame B-ultrasound image is analyzed; then, according to the terrain bright band in the B-ultrasound image The grayscale and gradient features of the model (there is a sudden change process) and the continuity of the model terrain in the horizontal direction can realize the single-pixel extraction of the terrain boundary line in a single frame image at one time; Similarity Cubic spline interpolation was performed to reconstruct the underwater 3D terrain. This method has good penetration and strong adaptability, and is suitable for underwater model terrains such as plastic sand, natural sand, coal ash, bakelite powder, etc.; the running speed is fast, and the single running time is less than 0.1 second; the measurement accuracy is high, The error of the underwater topography after a single measurement and reconstruction is less than 1 millimetre; it is intuitive and visual, efficient and fast, and effectively eliminates the imaging interference of irrelevant moving suspended particles in the water, and reproduces the original appearance of the underwater topography.

Description

technical field [0001] The patent of the invention belongs to the technical field of hydraulic model topography measurement, and in particular relates to a visual measurement and three-dimensional reconstruction method of model topography in muddy water. Background technique [0002] The river engineering model experiment is an important means for people to understand and study the river water and sediment movement, evolution and flood evolution law. In model tests, the real-time observation and analysis of underwater topography is of great significance to the study of river siltation and water erosion. In order to accurately obtain information such as underwater topography and its erosion and deposition changes in model tests, it is necessary to find a device for real-time dynamic observation and analysis of underwater topography information. In recent years, a variety of measuring instruments have been developed at home and abroad to measure the terrain of river engineeri...

AI Technical Summary

Problems solved by technology

In recent years, a variety of measuring instruments have been developed at home and abroad to measure the terrain of river engineering models, such as photoelectric reflection topographs, resistive topographs, tracking topographs, ultrasonic topographs, laser scanners and other instruments. At present, these terrain Most of the instruments are point-based measurements, which cannot realize non-contact multi-point online real-time image measurement and 3D reconstruction analysis of underwater model terrain, especially for underwater model terrain in the case of turbid water flow in moving bed model tests

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