Optimum Support Structure Generation for Additive Manufacturing Using Unit Cell Structures and Support Removal Constraint

Abstract Additive Manufacturing (AM) is the process in which a part is built using a layer by layer approach. Due to the inherent nature of the process, support structures are required to support overhanging features while building a part by AM. Support Structures increase the build time and cost of manufacturing and also have an adverse effect on the surface finish of the part. This paper presents a new approach for minimizing support structures using space filling cellular structures in conjunction with Dijkstra's shortest path algorithm to generate optimized support structures. Further, additional support accessibility constraints are applied to the support generation algorithm to ensure the ease of removal of the supports after manufacturing the part. The algorithm is validated by simulating the supports for two test parts while performing FEA analysis to test whether the generated structures are capable of supporting the weight of the part. A third test case is presented to verify the results of the algorithm using the support accessibility constraint.

[1]  Flaviana Calignano,et al.  Design optimization of supports for overhanging structures in aluminum and titanium alloys by selective laser melting , 2014 .

[2]  Hamid Nayeb-Hashemi,et al.  Mechanical properties of open-cell rhombic dodecahedron cellular structures , 2012 .

[3]  Ratnadeep Paul,et al.  Process energy analysis and optimization in selective laser sintering , 2012 .

[4]  Suk-Hwan Suh,et al.  Machinability and set-up orientation for five-axis numerically controlled machining of free surfaces , 1997 .

[5]  Seth Allen,et al.  On the Computation Of Part Orientation Using Support Structures in Layered Manufacturing , 1994 .

[6]  Daniel Thomas.  The development of design rules for selective laser melting , 2009 .

[7]  Chee Kai Chua,et al.  Development of a Tissue Engineering Scaffold Structure Library for Rapid Prototyping. Part 1: Investigation and Classification , 2003 .

[8]  T. C. Woo,et al.  Computational Geometry on the Sphere With Application to Automated Machining , 1992 .

[9]  Rutuja Samant,et al.  Support structure accessibility and removal in Additive Manufacturing using octree data structure , 2015 .

[10]  R. Everson,et al.  Advanced lattice support structures for metal additive manufacturing , 2013 .

[11]  K. Wegener,et al.  “Assessing new support minimizing strategies for the additive manufacturing technology SLM” , 2013 .

[12]  Sam Anand,et al.  Optimum Part Build Orientation in Additive Manufacturing for Minimizing Part Errors and Support Structures , 2015 .

[13]  F. E. Wiria,et al.  Selective laser sintering adaptation tools for cost effective fabrication of biomedical prototypes , 2010 .

[14]  C. M. Cheah,et al.  Development of a Tissue Engineering Scaffold Structure Library for Rapid Prototyping. Part 2: Parametric Library and Assembly Program , 2003 .

[15]  Edward J. Garboczi,et al.  Elastic properties of model random three-dimensional open-cell solids , 2002 .

[16]  Richard M. Everson,et al.  A new approach to the design and optimisation of support structures in additive manufacturing , 2013 .

[17]  Ratnadeep Paul,et al.  Optimization of layered manufacturing process for reducing form errors with minimal support structures , 2015 .

[18]  Jianhua Mo,et al.  Sloping wall structure support generation for fused deposition modeling , 2009 .

[19]  Larry Jones,et al.  Support Generation for Fused Deposition Modeling , 1995 .

[20]  Michiel H. M. Smid,et al.  Minimizing support structures and trapped area in two-dimensional layered manufacturing , 1999, Comput. Geom..

[21]  Edsger W. Dijkstra,et al.  A note on two problems in connexion with graphs , 1959, Numerische Mathematik.

[22]  Deborah J. Medeiros,et al.  Part orientations for CMM inspection using dimensioned visibility maps , 1998, Comput. Aided Des..

[23]  Han Tong Loh,et al.  Multi-orientational deposition to minimize support in the layered manufacturing process , 2003 .

[24]  Debasish Dutta,et al.  A review of process planning techniques in layered manufacturing , 2000 .

[25]  Martin Leary,et al.  Optimal topology for additive manufacture: A method for enabling additive manufacture of support-free optimal structures , 2014 .

[26]  Jouni Hänninen.  DMLS moves from rapid tooling to rapid manufacturing , 2001 .