So, I am trying to make a braille reader that uses an Arduino to scan in braille dots. The way I intended initially was to use three digital sensors to detect bumps and a scroll wheel to see the distance traveled so it knows when a new dot starts. This idea seems to be difficult because of switch bounce and how large the limit switches are.
I am switching my approach to some sort of optical input to the Arduino and an algorithm to see where braille dots are then translating later. This seems like it might work but I need to know what type of Optical sensor I can slide across the braille to create a really long image almost like a panoramic photo that has a line of braille. I would then use an algorithm to figure out whether a dot is present or not.
At the moment I am looking at either optical or ir cameras but I need to ensure it would work for this use and would have panoramic abilities.
Have you considered using 6 switches and reading them all concurrently and then debounce them concurrently, that will drastically reduce the load on the Arduino.
There exists a Braille "tickertape" - where actuated pegs protrude from holes, scrolling the text horizontally. Consider a mechanical mirror of this with plungers actuating microswitches?
If you shine a light at the page at a certain angle then the little bumps make shadows. I would imagine that an OCR type software could read that from an image.
Operated like the slide rule, but the braille-reader is held in place by mass and adhesion, operating the slide with one hand. The slider has three columns of plunging pins (for redundant, error correction) inside barrels. The barrels sense the plunger movement, having three states: 0 = plunge, 1 = nominal, 2 = lift. The sensing would be Hall effect (plunger moving past a magnet) or optical (plunger blocking or passing light). The dot-columns in each character are counted for timing (character two columns, space - pins nominal).
