A portable, handheld device that captures printed text using a small camera and converts it to Braille in real time. Designed as a senior design project to help visually impaired readers access printed material without requiring a computer or internet connection.
The system integrates a camera module, an 8-bit microcontroller, and a custom 2×3 solenoid array that physically forms Braille characters. The entire image processing and character recognition pipeline runs on the embedded processor, with the recognized letter driving solenoids to push or retract individual pins.
Select a letter to watch the signal flow through the device — from camera capture through the processing pipeline to the Braille cell output.
A compact OV7670 camera module captures a frame of the printed character and transfers it to the microcontroller via an 8-bit parallel interface. The image is converted to grayscale, binarized with an adaptive threshold, and segmented to isolate the character.
The segmented character is normalized to a fixed size and compared against a library of stored letter templates using cross-correlation. The template with the highest match score determines the recognized character.
The recognized letter is mapped to its Grade 1 Braille representation — a 6-bit pattern for the 2×3 dot matrix. An H-bridge driver circuit drives 6 push-pull solenoids that extend or retract to physically form the Braille character.