How do you create Bliss-based tactile symbols to help your students/clients develop communication skills?
Before describing the process of designing your own tactile symbols, you should know that we have already made available to you pre-designed and ready-to-print symbols in STL format for 242 core concepts. These STL files are based on the default settings of the designer, so they have no added Braille, text engraved on the sides, a recess on the back for you to put a 15 mm Velcro dot, and an internal pocket for inserting an RFID tag. [You don’t need to insert a tag if you’re not going to use the symbols with a Voice It device.]
All of this is to say that you may never need to design another symbol. You may be able to accomplish all your goals with the pre-designed symbols.
If you need additional symbols or if you need a modified version of the existing symbols, or if you’re just curious about what the symbol designer can do, read on.
First things first
You’ll need to do two things before you can begin using the symbol designer:
- Go to Printables.com and download the Bliss_Tactile_Symbols.zip.txt file you find there. Delete the “.txt” part of the file name and then expand the contents of the ZIP file in a convenient location.
Note, you may have to change your settings to see the “.txt” part of the file name. If you download the file and the name looks like this:
Change to the “View” tab and check the box named “File name extensions”:
Now the file name will look like this:
And you can rename it to remove the .txt part of the filename. You’ll be asked if you’re sure you want to change the file name. Click on “Yes”.
Now the file will look like this and you can expand it. - Now open that folder and you’ll see four subfolders and five files:
The “Bliss Tactile Symbols.scad” file is the symbol designer and the .json file, by the same name, contains a set of saved symbol configurations (called Presets). [The other two .scad files are described here: Bliss Tiles and Puzzles, Bliss Graphic STL maker.]
- Next, you need to download and install the free program, OpenSCAD. Instructions can be found here. [The instructions reference a different designer, “keyguard.scad”. Instead, you’ll be loading the file “Bliss Tactile Symbols.scad”, that you just downloaded from Printables, into OpenSCAD.]
The Designer Window
When you launch the designer within OpenSCAD, you’ll see the symbol designer user interface. The designer has three sections. On the left is a display that provides a view of your symbol as it is currently defined. On the right is the Customizer pane. You’ll do all your work here. Below the display region is the Console window. For the most part you can ignore this window until you’re ready to print your symbol design.
The Customizer Pane
The Customizer Pane has two regions. The upper region is where you access and create Presets. Below that is a set of expandable sections where you specify the values of several options for your symbol:
Click on the arrowhead to the left of each section to expand it. You’ll start at the top section and proceed downward when defining your own symbol. [Alternatively, you can start with a preset that has already been created for a symbol. These are the Presets associated with the ready-to-print symbols in the “STL files” folder. More on that below.]
Symbol Info
The Symbol Info section gives you with several options to control the size and shape of your symbol:
Begin by choosing a width for your symbol:
You can choose a width for your symbol sufficient to accommodate your Blissymbol. You may decide to come back here once you’ve chosen your graphic to make the symbol wider or narrower.
Now choose the type of word/concept for which you will be creating a tactile symbol.
Your choice will affect the shape of the top edge of the symbol and will serve as a tactile indication of the word/concept class associated with the symbol. Each entry begins with a special character that will give you a hint about the edge shape:
| noun, pronoun, preposition | verb | adjective, adverb, determiner |
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The last choice produces a flat top-edge and is appropriate when you put a series of words/concepts together on a single tactile symbol (e.g., “I love you”).
Next choose the thickness of your symbol by setting the “symbol thickness” in millimeters. Note that your symbol must be at least 8 mm thick if you want to put braille on the sides of the symbol.
You can resize your symbol, as a whole, if you need a larger or smaller symbol.
Choose a display color for your symbol:
Each color is followed by the word/concept class associated with that color in the Fitzgerald Key.
As you’d expect from the name, the color you choose is for display purposes only. You still need to choose the color of the filament you load in your printer. This option will help you better visualize what the symbol will look like if you load that color into your printer.
You can indicate whether you want to insert an RFID tag into the symbol during printing. This is the default. The RFID tag is intended for use with the Voice It device described here. If you select “yes” a pocket will be included in the symbol that is large enough for a 30 mm RFID tag. Selecting “yes” but not inserting an RFID tag, won’t stop you from printing the symbol and won’t make the symbol look strange. So if you accidently choose “yes” but didn’t intend to insert a tag, don’t worry, just go ahead and print the symbol – it will look fine.
Finally, you can add pockets for placing mounting magnets inside the symbol or adding recesses for 10 mm Velcro dots on the back surface of the symbol. The Velcro recesses can be placed in four corners (the default) or a single recess in the center. If you go with a single, centrally located recess, you can move it vertically to best match your needs.
Graphic Info
The raised graphic you’ll put on your tactile symbol will be a Blissymbol.
A set of “core words” and their associated Blissymbols have been pre-configured for you to use. Just select the word from the “core word” pull down list:
[Alternatively, you can choose your own graphic by typing the name of that graphic (without the .stl part) in the “beyond core word” box. You must have already put the associated STL file in the “beyond core words” folder. The name of the file must match what you type into the “beyond core word” box – followed by “.stl”. We provide an OpenSCAD program specifically for turning Blissymbol “.svg” files into “.stl” files ready to include on your symbol. Learn more about creating your own “tactile-symbol-ready” Blissymbols here.]
The “graphic height” option controls the distance that the graphic will extend beyond the face of the symbol:
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| graphic height = 1 mm | graphic height = 5 mm |
The Blissymbol will automatically be placed in the center of the tactile symbol and you may need to move it up or down vertically to place it where it belongs relative to the earth line and skyline. You can control that vertical placement with the “slide graphic vertically” option.
You can choose a display color (black or white) for the graphic. As the name implies, this is just for display purposes and to help you visualize your symbol. The graphic will only be a different color if you can swap filament colors during the 3D-printing process. We recommend that you use contrasting colors for the symbol body and the graphic (if you can) to aid individuals with visual impairments as much as possible.
Finally, you have the option of including or hiding the earth and sky lines. Note that the earth and sky lines may be necessary for proper interpretation of a Bliss graphic. However, if you believe that the lines are distracting to your student and you are confident that removing the lines won’t cause confusion, you can do so.
Symbol Text and Braille
You can determine whether the word associated with the symbol should be engraved on the underside of the symbol, as well as, whether the word should be represented in Braille on the edge of the symbol:
Enter the text that should be included in engraved form and/or as braille in the “symbol text” box. This will often be the same as the selected/entered word associated with the graphic image but you may want to use a word that is different from the one that was part of the filename or multiple words that represent the same concept (e.g., “do” and “does”).
If you are working with a student for whom, English is a second or developing language, you can choose word(s) from a more appropriate language.
Engraved Text
By default, the text you enter in the “symbol text” box will be engraved on the sides of the symbol. You can turn this off by setting the “engrave text” pull-down list to “no”. You can place the text on a different surface by choosing a different option from the “text location” pull-down list:
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| front* | back |
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| sides (default) | end |
* Note that selecting “front” as the location of the text will cause the text to initially appear in the vertical center of the symbol. You will need to move the text vertically so that it doesn’t interfere with the Bliss graphic.
You can choose between regular or bold text. You may find that bold text prints better on your printer than regular text. Text height controls the vertical size of the text.
The Bliss Tactile Symbols are often taller than they are wide. You may want to rotate longer words so you can take advantage of this longer dimension.
If you place text on the front or back of the symbol, you can control both its vertical and horizontal location. if you place the text on the sides or end of the symbol you can only control its horizontal location.
Braille
If you set “include braille” to “yes”, Braille for the symbol text will be placed on the edge of the symbol. The symbol designer displays a subset of Braille ASCII (or more formally The North American Braille ASCII Code, also known as SimBraille). The designer only supports lower and uppercase letters and spaces entered into the symbol text box. It converts all uppercase letters to their lowercase equivalent.
You cannot have both Braille and engraved text on the sides of the symbol. If you want to have both Braille and engraved text on your symbol, place the text on one of the other surfaces.
Your symbol must be at least 8 mm thick in order to display Braille on the side. With an even thicker symbol, you can increase the size of the Braille. This might make it easier for the individual to inspect and read the texture. A value of 10 for “braille size multiplier” produces standard size Braille.
If necessary, you can slide the Braille horizontally along the edge of the symbol by using the “slide braille horizontally” option.
Hole for String
You can “string” together several 3D-symbols to provide easier access for the individual who will be using them to communicate. The symbol designer gives you several options for placement and size of the string hole – including, no hole at all.
The following images show holes from side to side of the symbol. The top images show the hole going through the top of the symbol and the bottom images show the hole going through the bottom of the symbol:
You may find that it’s easier for the user to explore and understand the graphic if the hole goes though the bottom of the symbol.
Finally, you can put a hole through the symbol from front to back – at the top or bottom of the symbol:
You may find that a front-to-back hole lets you put more symbols on the string than a side-to-side orientation. The problem with a front-to-back orientation is that it the hole location might interfere with the graphic and you’ll need to keep the hole small.
If the initial position of the hole interferes with the graphic or results in other issues for the symbol, use the “move hole vertically” slider to move the location further toward the top of the symbol or further toward the bottom.
Using the Ready-Made Presets and Creating Your Own
At the top of the Customizer pane, there are some controls that allow you to save your settings for a symbol and recall them later. We’ve done that already for our 242 core words/concepts.
On the left is a pull-down list of saved, presets. Each preset stores all the option values at the time you save the preset. A special preset called “design default values” represents the default values of all options when you first start the program. Click on the pull-down arrow and you’ll see the presets that we’ve already created for you:
If you make a change to a saved preset by changing the value of an option, an asterisk will appear to the right of the pull-down list. You can save the change by clicking the “save preset” button. To create a new preset, click the “+” button and give the preset a name. To delete a preset, choose it from the pull-down list and then click the “-” button.
Presets are saved in the “Bliss Tactile Symbols.json” file. If you do a lot of work to create your own symbol definitions, you might want to back up this file along with the “beyond core words” folder.
Putting it all together
If video works better for you, this recording demonstrates the way that the various configuration options work together:
3D-Printing a Bliss Tactile Symbol
The following video shows how a tactile symbol is sliced and printed – including insertion of an RFID tag and changing filament colors to make the Bliss graphic stand out for visually impaired individuals:
Attaching Velcro (i.e., “hook & loop”) Mounts
We recommend that you place the “hook” half of a hook and loop mount to the tactile symbol itself. Normally, the surface, to which you mount the symbol, will be fuzzy and serve as the “loop” side of the connection.
If you’re having trouble getting the dot to stick, try the approach described on this page.