Research On Automatic Generation Algorithm Of Part Build Orientation For 3D Printing

Selecting the optimal build orientation of a 3D printed part from several candidate build orientations is a typical decision-making problem,where each candidate build orientation have various attributes and characteristics.How to accurately describe the attribute information of each candidate build orientation,evaluate the candidate build orientations and generate a priority sequence? In order to solve the above problems,a fuzzy set-based multi-attribute decision-making method can be introduced.At present,the research on fuzzy multi-attribute decision-making has made great progress.However,the existing methods based on fuzzy aggregation theory have the following shortcomings when making multi-attribute decision-making for candidate build orientations of 3D printed parts.First,the relationship between the attributes of the candidate build orientations is ignored.The existing fuzzy aggregation methods used to assume that the attributes are independent of each other,which is difficult to solve the problem of complex attribute relationships in actual decision-making.Second,for extreme attribute values,the existing methods cannot avoid its negative impact on the results of multiple-attribute decision-making in candidate build orientations.Aiming at the above problems,this paper proposes a multi-attribute decision-making method based on fuzzy information composite aggregation operator.On this basis,combined with the positioning method of the candidate build orientations of the part,an algorithm model for the automatic generation of the optimal build orientation is proposed,which is aimed at the parts formed by the SLM process in the field of 3D printing.The research contents of this paper are as follows:(1)A multi-attribute decision-making method based on WFAPMM operator and WFAPGMM operator is proposed.The WFAPMM aggregation operator is proposed by combining the MM operator and the PA operator,the WFAPGMM aggregation operator is proposed by combining the GMM operator and the PA operator,and a new multi-attribute decision-making method based on the WFAPMM and the WFAPGMM operator is proposed.Firstly,the aggregation function of the proposed operator is given.On this basis,the general expression of the aggregation operator is calculated and the properties of the operator are discussed.Then the two operators based on Hamacher t-norm and t-conorm are derived respectively concrete expressions.A new method for solving the multi-attribute decision-making problem is developed.Finally,the proposed multi-attribute decisionmaking method is verified by experimental cases and comparative analysis.(2)A method for determining the candidate build orientations of SLM parts is designed.Input the STL model of the SLM part,use the HDBSCAN clustering algorithm to cluster the triangular face normal vector in the STL model of the part,select the appropriate cluster density according to the clustering steps and output the corresponding cluster;according to the number of clusters,judge whether to carry out Refinement,calculating the build orientations of the final determined clusters,and summarizing the candidate build orientations of the SLM part.(3)An automatic generation algorithm for the optimal build orientation of SLM parts is designed.By using the fuzzy multi-attribute decision-making method to solve the problem of searching for the optimal build orientation,a new positioning algorithm for the build orientation of SLM parts is proposed.The main process of the algorithm is as follows:on the premise of generating a candidate set of SLM parts build orientation,select the main attributes of the part,and construct a decision matrix after estimation by the prediction model;fuzzy and normalize the decision matrix to obtain a standard fuzzy decision matrix;calculate the comprehensive preference score of the alternatives with fuzzy aggregation operators;outputs the priority sequence of the alternatives and find the optimal build orientation of the SLM part.