The effect of orientation on the readability and comfort of 3D-printed braille

Hand-drawn sketches of various elements of the experiment. On the left, the drawings depict the differences between a braille cell's theoretical and actual shapes. In the middle, the sketches show a depiction of a sander, and the annotations read: two sanded experiments (sanded and unsanded). On the right, the drawings show the experimental setup, including a sketch of the table and the page of braille with the stimulus. At the bottom are a side view of the printer with plates printed at various angles, and a front view of the braille in one print.
The shape of a 3D-printed object is affected by its orientation, as shown by the top left image. Therefore, we designed two experiments to determine if this impacted the experience of braille readers. These experiments differed by whether the stimuli were sanded, as shown in the top middle illustration. On the top right is a sketch of our experimental setup. Finally, below are some photographs of the experiment stimuli.
Fused Deposition Modeling (FDM) is a low-cost method of 3D printing that involves stacking horizontal layers of plastic. FDM is used to produce tactile graphics and interfaces for people with visual impairments. Unfortunately, the print orientation can alter the structure and quality of braille and text. The difference between printing braille vertically and horizontally has been documented. However, we found no comprehensive study of these angles or the angles in between, nor any study providing a quantitative and qualitative user evaluation. We conducted two mixed-methods studies to evaluate the performance of braille printed at different angles. We measured reading time and subjective preference and performed a thematic analysis of participants' responses. Our participants were faster using and preferred 75° and vertical braille over horizontal braille. These results provide makers with guidelines for creating models with readable 3D-printed braille.
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Cody Dunne, Vis Lab — Northeastern University
West Village H, Room 302F
440 Huntington Ave, Boston, MA 02115, USA