Tact: A Zero-Cost, Browser-Based Pipeline for On-Demand Tactile Braille Storybooks

Abstract

Braille literacy among blind school-age children fell from roughly 50 percent in 1960 to under 10 percent today, and the decline is a content problem, not a technology problem: producing one illustrated braille page still requires specialized software and trained labor, so almost nothing in the existing catalog is personalized to an individual child. We present Tact, a system that converts a spoken or typed story idea into a printable braille page with a matching raised tactile illustration, computed inside a web browser with no account and no mandatory cost, and able to run with no server at all. This paper documents the full engineering history behind that system, rather than a narrow slice of it. It covers the target population and the ethical framing behind an explicit sighted-operator model, the hardware rationale for desktop fused deposition modeling over purpose-built embossing, and the physical braille geometry and its printer-specific calibration. It documents the architecture that lets a language model run on the reader’s own device, the later addition of a faster hosted path in front of it after an independent reimplementation exposed the cost of a 1.8 gigabyte first-use download, and the fallback chain that keeps the system working when that path is absent, the investigation that replaced a general-purpose braille translation library with a small deterministic implementation after it failed in production, and the evolution of the page layout from an inherited portrait specification to a verified square design, and its later revision from the field feedback of a teacher of blind readers. It further documents the construction of a 93-shape hand-drawn tactile illustration library derived from a frequency study of fairy-tale subjects, and the synthesized sound design used to make a voice-first interface legible without a screen. We report the verification performed to date, the ethical commitments the project has made, and the work required before the system can be considered ready for real blind and low-vision readers.