Wavelet transform-based self-adaptive compression method for STL (Standard Template Library) grid model slicing data

Abstract

The invention discloses a wavelet transform-based self-adaptive compression method for STL (Standard Template Library) grid model slicing data. The method comprises the steps of: reading an STL grid model in an ASCII (American Standard Code for Information Interchange) format, extracting point, side and surface information of triangles in the STL grid model, and establishing a topological relation; determining the slicing depth of each layer in the STL grid model according to the size of the read STL grid model and a needed sliced position; solving intersection point coordinates of slicing and one layer of the STL grid model, and carrying out self-adaptive compression and optimization sliced data by use of wavelet transform; after one layer is sliced, entering the next layer for slicing until all slicing fragments are traversed, and after slicing is completed, generating a contour loop. According to the method, the peak value of wavelet coefficients can self-adaptively detect characteristic points of data; through wavelet decomposition for intersection point data, wavelet reconstruction is completed and low-frequency and high-frequency coefficients are obtained; and through analysis for coefficients and input of signals and obtaining of quantified analysis results, the rejection of fault data and the adjustment of point cloud sparsity are completed.

Description

technical field [0001] The invention relates to the field of additive manufacturing, in particular to an adaptive compression method for STL grid model slice data based on wavelet transform. Background technique [0002] With the continuous development of additive manufacturing technology, 3D printing technology has become a cutting-edge and leading emerging technology, and it is more suitable for product design and development, small-batch personalized customization, and products with complex models. In all additive manufacturing processes, whether it is normal modeling through CAD modeling software or a mesh model of a part generated through reverse engineering technology, it must be processed in layers and slices before the file data can be input into the molding device. Therefore, the accuracy of layered slice data has a greater impact on 3D printed products. [0003] The Stereo Lithographic (STL) data format was invented by 3Dsystems and is widely used in reverse engin...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problems of reduced slicing accuracy and cumbersome slicing data due to the STL format, the present invention provides a method for adaptively compressing STL grid model slicing data based on wavelet transform, which slices the triangular grid through the slicing plane, and obtains For the slice intersection data of this layer, the wavelet transform can be used to eliminate the error data caused by the data format and make the sliced ​​model smoother

Images