I think an alternative approach would be to have some sort of woven fabric loop that can have raised braille dots stitched into it from the right side and then the loop is pulled to the left. So it would read like one of those scrolling LED banners except it would be a fabric belt with raised dots.
Maybe the simplest approach mechanically would be to have Nitinol wires running vertically, parallel to the 'weft' thread. To print a single letter in Braille would require stamping two Nitinol wires to render the raised dots in the correct positions, and then feeding the fabric belt to the left. On the return side, hidden underneath the display, the Nitinol wires could be returned to their original state.
Alternatively, any technique that could raise a knot in the fabric which could then be easily released would be worth pursuing. That could be as simple as something that pushes a loop up (for a braille dot) through the fabric belt and then pulls it back out on the return trip.
Maybe the simplest approach mechanically would be to have Nitinol wires running vertically, parallel to the 'weft' thread. To print a single letter in Braille would require stamping two Nitinol wires to render the raised dots in the correct positions, and then feeding the fabric belt to the left. On the return side, hidden underneath the display, the Nitinol wires could be returned to their original state.
Alternatively, any technique that could raise a knot in the fabric which could then be easily released would be worth pursuing. That could be as simple as something that pushes a loop up (for a braille dot) through the fabric belt and then pulls it back out on the return trip.