Study On Filling Algorithm Of Interlayer Steering Path In Selective Laser Melting Forming Software

Selective laser melting forming is a processing method in which complex structures are sliced and layered and accumulated layer by layer to form a three-dimensional entity.It has the advantages of high integration and fast forming speed.It plays a key role in the fields of medical instruments and aerospace equipment.The role of model slice processing line scan path fill strategy as selective laser melting process key step in the formation,the forming profound effect.However,the current selective laser melting forming supporting software generally has problems such as narrow application scope and incomplete model processing functions.This paper has developed a database based on Open Cascade,Qt,etc.through full research on the selective laser melting forming process and software development process.The slicing software designed the import and export algorithm of model data,realized the slicing of models in multiple formats,and finally constructed the scanning algorithm of the odd and even layer of the outer contour offset,and optimized the data storage form.The main contents and conclusions are as follows:(1)The information extraction results in different formats and import the model file.Analysis of the parameters of the discrete file format advantages and disadvantages,by calling the corresponding data in the interface Open Cascade achieve extraction and introduction of STL,STEP,IGES file format model information.Design optimization algorithm redundant bytes triangular facets information has been removed while the three formats file keywords and their meanings were consolidated,the similarities and differences co-ordinate different file storage format developed to handle.The model information extraction algorithm of three formats realizes the model import processing of different format files.(2)Developed a model slicing algorithm that is compatible with multiple formats and can set the layer spacing.By three-dimensional model of the slicing process were analyzed and found that the process can be simplified as the process section in several Boolean intersection operation between the slice plane and the three-dimensional model,thereby Open Cascade designed by calling the class model sections Brep Algo algorithm.While achieving the function of rotating the model,to facilitate changing the direction of the slice according to actual demand,the calling function gp?Pnt gp?Dir completes the creation of the slice plane,but also by changing the numerical parameters SThicness thereby changing the slice thickness,slice after The independent line segments are connected through the function Connect Edges To Wires.The final configuration is determined relationship between the contour ring contains an algorithm contained alone contour ring number,and the contour ring taken sliced ordered information storage.(3)Constructed a hierarchical reversing scanning path line filling strategy based on offset within the contour.Layered reversing scanning can effectively solve the problem of surface warpage defects caused by residual stress during the forming process.In this paper,the layered reversal and the angle of reversal are realized by rotating the odd and even layers in the slice layer at a certain angle.Can be flexibly set by the user.Before proceeding to the outer contour of the filling path is a scanning region offset a certain distance,the offset distance can be changed by changing the parameters,which can effectively avoid the forming region of the edge contour of the phenomenon of poor quality.The inner contour of the adjacent scanning lines are connected end to end,thereby reducing the number of idle stroke travel of the laser.Bubbling region designed path algorithm obtained sorted,such rapid contour path information storage stable and orderly.A path implements an iterative loop optimization algorithm,higher accuracy compared to the conventional algorithm and the recursive algorithm efficiency.(4)The Gcode code generation for the final scan path line data is realized.Gcode commonly used devices and the key data codes in the command selective laser melting molding were consolidated,data path lines obtained were discrete,so as to have a better device compatibility,while the repeated data node removal.Reduce the redundancy of the result file,realize the export of the scan path line data through the file stream output outfile,and finally generate it to the file cura.gpath.