Laser point cloud data-oriented broad-leaved tree real leaf modeling and deforming method

Abstract

The invention discloses a laser point cloud data-oriented broad-leaved tree real leaf modeling and deforming method comprising the following steps: first, acquiring an accurate leaf border from a scanned leaf point cloud through a polynomial fitting method, and calculating the main vein of the leaf surface based on a computer graphics method; second, fitting leaf surface point cloud data by using a double-cubic generalized tensor product Bezier curved surface to remove scanning error caused by wind shaking and eliminate noise point cloud; and finally, defining different mechanical properties of the veins and mesophyll according to a solid mechanics force model, constructing a stress deformation equation of a nonlinear finite element, calculating the leaf shape after different load forces are applied, and simulating the real deformation of leaves in a natural environment. According to the invention, forestry indexes are acquired by a computer through automatic analysis, and the leaf area index indicating dynamic growth change of standing trees under different forest stand conditions can be described accurately. The method is of certain use value.

Description

technical field [0001] The invention relates to a method for modeling and deforming real blades of broad-leaved trees oriented to laser point cloud data, in particular to a method for modeling and deforming the leaves of broad-leaved trees based on LTS (TransportLayerSecurity, laser scanning) point cloud data. Background technique [0002] Broad-leaved trees generally refer to dicotyledonous trees, which have flat, relatively broad leaves, reticular veins, evergreen or deciduous leaves, generally broad leaf surfaces, and leaf shapes that vary from tree species to perennial woody plants. Some are evergreen, and most of the deciduous leaves fall from the branches in autumn and winter. Broad-leaved trees have great economic value, many of which are important timber species, some of which are precious wood, landscape plants, various fruits, etc., and some broad-leaved trees are used as street trees or garden greening trees. The research of the present invention is the reconstru...

AI Technical Summary

Problems solved by technology

But so far, it has not been found to use discrete point cloud leaf data for modeling. This is mainly because the shape of trees is irregular and complex, and the external environment has a continuous impact on the state of trees. Obtaining point cloud data without external environmental influences Technology is difficult; therefore, considering the use of computers to automatically model and morph broadleaf tree leaves requires solving a number of problems:

[0005] 2) The trees are luxuriant, and the shape and azimuth angle of the leaves are not fixed. How to identify and distinguish the point cloud data of different leaves from the laser-scanned tree point cloud is a difficult problem to be solved;

[0006] 3) Laser scanning is due to disturbance and occlusion of the external environment, and there are deviations and jitters in the scanned data. How to remove the deviation and obtain the real deformed leaf surface data is a problem that needs to be considered;

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