Design principles for tactile graphics

Tactile graphics (raised line drawings) differ from print in that they are read one element at a time and less detail can be conveyed. It is not necessary to reproduce the exact appearance of the print in a tactual diagram. Instead, simplification is often required.

Planning is the key to a successful diagram. If the touch reader will not be relying on sight, it is fine to do a rough drawing of the diagram on the page before creating the tactile elements on a handmade tactile graphic.

Items should be tactually distinct. For example, arrow heads should not touch the item to which they are pointing. e.g. arrow and box with space between (not arrow with head touching a box).

Check the tactual diagram with your fingers – not with your eyes.

Lines

Lines with different meaning should be tactually distinct. Produce them using different methods, or use different types of lines such as single solid line single solid line, single dashed line single dashed line and double solid line two parallel solid lines.

When two lines intersect, the less important line should be broken to allow uninterrupted tracing of the important line. e.g. solid continuous line intersecting with a dashed line. There are blank spaces around the solid line.

Arrows should have open heads, e.g. arrow with head composed of two straight lines (not arrow with solid triangular head). Do not join arrow heads to the target item.

Braille labels

All diagrams should have appropriate labelling at the top of the page so the reader can identify and link it with their other materials. As a minimum, the source and page number should be given. e.g. lec2 slide34.

When planning a diagram, keep in mind that braille labels require a lot of space. It may sometimes be necessary to use a key. In this case, 2-letter symbols with mnemonic qualities are best, e.g. “au” for “Australia”.

Further resources


Last updated: August 8, 2018 at 14:08 pm