Tactile Graphics with a Voice Demonstration
Catherine M. Baker, Lauren R. Milne, Jeffrey Scofield, Cynthia L. Bennett, Richard E. Ladner · 2014 · Proceedings of the 16th International ACM SIGACCESS Conference on Computers & Accessibility (ASSETS '14) · doi:10.1145/2661334.2661349
Summary
This demonstration paper presents Tactile Graphics with a Voice (TGV), a system that makes labels on tactile graphics accessible to blind and low vision users who do not read Braille. STEM textbooks are filled with images — from parabolas to cell diagrams — that are essential for learning but cannot be conveyed by text alone. The standard accessibility approach converts these images into tactile graphics with embossed Braille labels. However, the National Federation of the Blind reports that only about 40% of the functionally blind population actually knows Braille, particularly those who become blind later in life. TGV addresses this gap with a two-part system: the graphics themselves, where text labels are replaced with QR codes that can be tactilely located, and an accessible smartphone application that scans and reads the QR codes aloud. Creating TGV-compatible graphics requires only minor modifications to the standard tactile graphic production process — instead of translating text to Braille, text is converted to QR codes using any free QR code generator, printed on adhesive-backed paper, and placed on the embossed image.
Key findings
The TGV smartphone application includes two key interaction features designed for non-visual use. First, it provides audio and haptic feedback to guide users in positioning the phone camera over a QR code, helping them successfully scan codes they cannot see. Second, it includes a "finger pointing mode" that allows users to select which QR code to scan when multiple codes are close together on the graphic — a common occurrence on detailed diagrams. The system is notable for its low-tech, low-cost approach: it leverages existing QR code technology and standard tactile graphic production methods, requiring no specialised hardware beyond a smartphone. The production process changes only two of three standard steps (replacing Braille translation with QR code generation), making it easy to integrate into existing workflows for creating tactile educational materials.
Relevance
This work highlights a critical and often overlooked accessibility gap: not all blind users read Braille, so Braille-only solutions for tactile graphics exclude a significant portion of the target population. For accessibility practitioners working in education, this is an important reminder that accessible alternatives need their own alternatives. The QR code approach is pragmatic and deployable — it does not require expensive equipment or significant changes to existing production workflows. The system is particularly relevant to STEM education accessibility, where graphical content is essential and often the hardest material to make accessible. While the paper is a brief demonstration companion to a full paper at the same conference, it effectively communicates the core problem and solution. The finger pointing interaction mode for disambiguating nearby QR codes represents a thoughtful piece of non-visual interface design applicable to other camera-based assistive tools.
Tags: tactile graphics · blindness and low vision · QR codes · STEM accessibility · braille · non-visual feedback · education · assistive technology