Reconfigurable Furniture Design And Model Structure Optimization For Material-saving 3D Printing

In recent years,as a new type of manufacturing process,3D printing technology has become more and more widely used in various industries including furniture manu-facturing,architectural design,medical equipment,etc.The technical characteristics of its layer-by-layer printing and layer-by-layer stacking of raw materials make it easy to manufacture a variety of complex shapes,which is unmatched by traditional manufac-turing techniques.In addition,3D printing technology has the outstanding advantages of low skill threshold and manufacturing cost independent of model complexity.How-ever,3D printing technology still faces some problems that need to be solved urgently.Among them,the problem of high material cost largely restricts the further development of this technology and has received extensive attention from the academic community.Under the above background,we propose two methods for saving printing materials from the perspective of computational design and geometric structural optimization.Firstly,from the perspective of computational design,we propose a computational design scheme for reconfigurable interlocking furniture.This scheme can generate a set of common parts according to a given set of furniture design forms,and assemble the set of common parts into corresponding interlocking furniture for use based on actual usage scenarios.On the one hand this scheme saves material consumption and on the other hand the resulting furniture parts can be easily assembled,disassembled and stored.Details are as follows:I)We use a dynamic bipartite graph model to co-decompose a given set of design models to obtain a set of reusable common parts;2)A half joint connection graph is proposed to model the connections between parts of multiple design models;3)We propose two new interlocking structure construction methods,namely,backward interlocking modeling and multi-key interlocking modeling;4)We propose a co-construction method for constructing interlocking structures on multiple assem-blies by planning compatible joints.Experiments show that the proposed scheme can efficiently design reconfigurable self-locking furniture models of different types and complexities,which reduces material consumption effectively.Secondly,from the perspective of structural optimization,we propose a shell model construction and optimization scheme based on stress distribution.Based on the stress distribution of the model,this scheme constructs a non-uniform thickness shell model that does not change the appearance of the model and meets certain strength constraints,which reduces the printing volume of the model greatly and saves printing costs effec-ively.Details are as follows:1)Constructing a directed distance field based on the voxel representation of the model and extracting a shell model of uniform thickness;2)Acquiring the stress distribution of the shell model and then expanding the inner sur-face based on the stress distribution adaptively;3)Support the optimization of material for large objects by assisting the user to segment the model,automatically construct the connection structure,and optimize the shell model simultaneously.Experimental re-sults show that the volume of the shell model generated by this scheme is 17.2%?24.4%of the input model,which reduces the printing volume greatly.