Annular neighborhood reference contour line-based grid model adaptive layering method

Abstract

The invention discloses an annular neighborhood reference contour line-based grid model adaptive layering method. According to the method, the maximum thickness and minimum thickness of layers and residual height accuracy values are determined; the annular neighborhood surface patch order of vertexes is adjustable; initial vertexes are selected from model grid vertexes to construct a reference contour line; the initial vertexes are recursively traversed, so that vertexes with the maximum Gaussian curvature are obtained; multi-criteria fitting is performed all the vertexes with the maximum Gaussian curvature are obtained; multi-criteria fitting is performed all the vertexes with Gaussian curvature extreme values, so that an annular neighborhood reference contour line can be obtained; and grid model layer thicknesses are adaptively set from bottom to top according to the non-monotonic form change rate along a layering direction; residual height analysis is performed on the thickness of each layer; the steps of the method are repeated, so that the layer thicknesses of a plurality of neighborhood reference contour lines are obtained; and iterative weighting is performed, so that the final thickness of each layer is obtained, and the splicing plane position of each layer is determined, and splicing is performed. With the method of the invention adopted, the inner and outer surface forms of a grid model can be expressed in a multi-dimension manner, the accuracy of adaptive layering and slicing can be improved, and the high-precision layering and slicing of a geometric grid model with sharp changes in the inner and outer surface can be facilitated.

Description

technical field [0001] The invention relates to a complex three-dimensional model processing method in the field of advanced manufacturing technology, in particular to a layer cutting method for a geometric grid model in the field of additive manufacturing. Background technique [0002] 3D Printing (3D Printing) is also known as Additive Manufacturing (AM), which can directly generate part models from CAD solid geometric data models. The 3D printing process is based on the cross-sectional graphics of each layer, and the height is the slice thickness Multiple cylinders are superimposed and accumulated in sequence. This processing technology will produce a Staircase effect on the inclined surface of the part, which will cause errors between the processed model and the actual model contour, and even cause morphological distortion of the part. Therefore, the analysis The effect of layer slicing directly affects the manufacturing efficiency and precision of parts. The evaluation...

AI Technical Summary

Problems solved by technology

The processing data models of 3D parts are mainly CAD solid models and geometric grid models. CAD solid models can fully express the actual outline, material and color information of the model, but when layered and sliced, there are large files and it is difficult to support the model and difficult to optimize; geometric mesh models mainly include STL, OBJ, PLY and other formats, which only retain the geometric information of three-dimensional objects and are easy to edit and optimize. Improving approximation accuracy through mesh refinement

[0006] These methods have their own advantages and scope of application, but there are still some limitations, especially for the layered slices of the mesh model with sharp changes in the inner and outer surface shapes, there is a problem that it is difficult to have both efficiency and accuracy, especially for multi-dimensional Mesh models with sharply changing shapes make it difficult to achieve high-precision and high-efficiency layered slicing

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