Personally, I would have looked at more options before going for the (rather large) motorized wheel route. Two that come to mind are reusing the ball-type powered typewriters from the 80s/90s since the balls had embossed letters and high-precision positioning already. A second is microfluidic displays, which cellphone makers toyed with for on-screen keyboard tactile feedback back in the early 2010s. And indeed a quick search shows that a University of Michigan team used exactly that for a braille display 8 years ago [1] and it's spinning out into a company now. The company that was working on this for "pop-up" touchscreens 10 years ago was Tactus [2]. On the electromechanical side, it looks like there's an open source movement already with some interesting results so far [3].
Personally, I would have looked at more options before going for the (rather large) motorized wheel route. Two that come to mind are reusing the ball-type powered typewriters from the 80s/90s since the balls had embossed letters and high-precision positioning already. A second is microfluidic displays, which cellphone makers toyed with for on-screen keyboard tactile feedback back in the early 2010s. And indeed a quick search shows that a University of Michigan team used exactly that for a braille display 8 years ago [1] and it's spinning out into a company now. The company that was working on this for "pop-up" touchscreens 10 years ago was Tactus [2]. On the electromechanical side, it looks like there's an open source movement already with some interesting results so far [3].
[1] https://www.youtube.com/watch?v=0fIg4rI4cDw
[2] https://www.youtube.com/watch?v=JelhR2iPuw0
[3] https://www.youtube.com/watch?v=BXi1tG78AW4