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Tactile symbols for production on a 3D printer: 3D Model
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The symbol set was designed for production on microcapsule paper by Amy Lobben 
and Megan Lawrence as described in the publication: 

Lobben A, Lawrence M (2012) The use of environmental features on tactile maps 
  by navigators who are blind. The Professional Geographer 64(1):95-108. 
  doi: 10.1080/00330124.2011.595619

The symbol set developed by Lobben and Lawrence (2012) was designed and 
evaluated as produced on microcapsule paper.  Those same symbol shapes were
modeled in low relief for production on a 3D printer.

3D models released under the GNU Public License (GPL) version 3.
Copyright (c) 2013, 2016 University of Oregon
Authors: Megen Brittell, Manny Garcia, Amy Lobben, Megan Lawrence
	Department of Geography
	1251 University of Oregon
	Eugene OR 97403-1251

This work was funded in part by the National Institutes of Health (NEI 
1RC1EY020316) and National Science Foundation (HRD 0930769).


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3D MODEL
The symbol set developed by Lobben and Lawrence (2012) was designed and 
evaluated as produced on microcapsule paper.  Those same symbol shapes were
modeled in low relief for production on a 3D printer.

Note: Evaluation of the models was conducted on products printed on a 
MakerBot Dual with 0.2 mm layer height

Note: The examples rendered at the bottom of each OpenSCAD (.scad) file 
are rendered in a single scene for demonstration.  When exporting to 
stereolithograph (STL) it may be necessary to render the pieces in 
several sub-groups so that all pieces within a single STL file will 
fit on the printer plate.  Even through the printer's pre-processing 
software may allow scaling of the pieces, this will change the sizes of 
the symbols and may influence symbol readability in the printed pieces.
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Fill Symbols
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tactileMapSymbols_3D_model_fill-thumbnail.png
	A graphic depiction of the 3D model in code and as rendered in 3D in
	the OpenSCAD scripting interface.

tactileMapSymbols_3D_model_fill.scad
	Script (ASCII) in OpenSCAD to implement the 3D versions of the six
	fill symbols.  The 3D models described in the OpenSCAD (.scad) files 
	are characterized by a series of numeric variables, then a collection 
	of modules that implement the fill symbols, and finally example use of 
	each of the fill symbols.  All fill symbols are rendered to fill a 
	square sample swatch; they could be clipped to fill a smaller area 
	without modification, but their definitions would need to be extended 
	to fill a larger area.


Line Symbols
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tactileMapSymbols_3D_model_line-thumbnail.png
	A graphic depiction of the 3D model in code and as rendered in 3D in
	the OpenSCAD scripting interface.

tactileMapSymbols_3D_model_line.scad
	Script (ASCII) in OpenSCAD to implement the 3D versions of the eight
	line symbols.  The 3D models described in the OpenSCAD (.scad) files 
	are characterized by a series of numeric variables, then a collection 
	of modules that implement the line symbols, and finally example use of 
	each of the line symbols.  All line symbols are rendered at a fixed 
	length; definitions may need to be extended if the line length varies.


Point Symbols
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tactileMapSymbols_3D_model_point-thumbnail.png
	A graphic depiction of the 3D model in code and as rendered in 3D in
	the OpenSCAD scripting interface.

tactileMapSymbols_3D_model_point.scad
	Script (ASCII) in OpenSCAD to implement the 3D versions of the fourteen
	point symbols.  The 3D models described in the OpenSCAD (.scad) files 
	are characterized by a series of numeric variables, then a collection 
	of modules that implement the point symbols, and finally example use of 
	each of the point symbols.  All point symbols are rendered at a fixed size 
	that matches the original point symbols reported by Lobben and Lawrence 
	(2012).  Any change in the symbol size should be accompanied by empirical 
	evaluation of readability.
