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

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 entirely inside a web browser with no server, no account, and no mandatory cost. This paper documents the full engineering history behind that system: 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 instead of a remote server, 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. 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.