BASICS
TYPES & FUNCTIONALITY
THE CODING PROCESS
A PPLIC AT IO N S
3D PRINTING: THE BASICS
Also called additive manufacturing, this process involves a printer with XYZ axis
which creates a 3-dimensional solid object from a digital model by laying down
successive layers of material in different shapes.
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Builds the object by deposition of material rather than by removal of material.
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Mediums range from paper, plastic, powders, resins, metals.
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Depending on your model, you will want a certain printer type and medium.
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Two Main Types of Printers (among many)
- Fused Deposition Modeling (FDM)
- Selective Laser Melting (SLM)
FUSED DEPOSITION
MODELING (FDM)
SELECTIVE LASER
M E LT I N G ( S L M )
Primarily read Standard Tessellation Language or STL files, our goal
was to find or develop a code which allowed easy transcription of .m
files into .stl files, and successfully print a model.
facet normal nx ny nz
outer loop
vertex v1x v1y v1z
vertex v2x v2y v2z
vertex v3x v3y v3z
endloop
endfacet
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Describes a closed surface in terms of
triangular faces
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Each triangle is described by cartesian
coordinates of its three vertices and a
normal vector oriented outward from the
closed surface
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A surface described by an STL-file must
then be sliced into layers using an external
software. This defines the path traced out
by the printer
MatLab Logo: The L-Shaped Membrane
1) Break up each square element in the mesh into two triangular
elements using the MatLab function Delauney.
Notice That the mesh has no thickness….
http://blogs.mathworks.com/community/2013/06/20/paul-prints-the-l-shaped-membrane/?s_eid=PSM_4977#1f9d71f8-8030-43d7-a639-a0388376118e
2) Make a shell out of the surface by projecting all the vertices of the
triangles downward along normal vectors.
3) Creates a second surface with no thickness beneath the original.
4) Connect the two surfaces along their boundaries to define a third
surface.
http://blogs.mathworks.com/community/2013/06/20/paul-prints-the-l-shaped-membrane/?s_eid=PSM_4977#1f9d71f8-8030-43d7-a639-a0388376118e
STLWRITE
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Creates STL file directly
from .m script
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Downloadable function
created for MatLab that
exports a binary STL (or
ascii) formatted version of
a script.
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Requires that your code
have triangulated patch
called FV, a structure with
fields ‘vertices’ and
‘faces’.
stlwrite (filename , FV)
http://www.mathworks.com/matlabcentral/fileexchange/20922-stlwrite-write-binary-or-ascii-stl-file
ADDITIONAL STEPS
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STL file now needs to be sliced
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Software called “Slic3r” (and others) cuts file up into 2-dimensional
cross sections of data, readable by printer
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Some printers read another basic format called G-Code. If that’s the
case when you go to print, this software will generate a G-Code from
your STL file.
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Use MeshLab for a 3D preview
http://meshlab.sourceforge.net/
http://slic3r.org/
APPLICATIONS
INTERESTED IN PRINTING?
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Eugene MakerSpace has printers for public use
Possibly getting a printer in the geophysics
department
Email me if you’re interested in printing something
or would like more info on how to prepare your
model for a printer.
LINKS
MatLab L-Shaped Membrane Steps
http://blogs.mathworks.com/community/2013/06/20/paul-prints-the-l-shaped-membrane/
STL WRITE
http://www.mathworks.com/matlabcentral/fileexchange/20922-stlwrite-write-binary-or-ascii-stl-file/content/stlwrite.m
Meshlab
http://meshlab.sourceforge.net
Slic3r
http://slic3r.org/
Downloadable STL files
http://www.thingiverse.com/