I love the write-up! Everything is there, and it is a fascinating read even to a layperson (to braille tech). Thanks for sharing.
Affordable Wheel Based Refreshable Braille Display
31–40 of 68 posts
Re: Affordable Wheel Based Refreshable Braille Display
#32FWIW, there’s already a commercially available braille display that uses spinning wheels:
Very interesting approach.
Re: Affordable Wheel Based Refreshable Braille Display
#33FWIW, there’s already a commercially available braille display that uses spinning wheels: https://bristolbraille.org Very interesting approach.
That exact machine is discussed in the article...
Re: Affordable Wheel Based Refreshable Braille Display
#34Fantastic effort, but oddly and almost shockingly archaic. This is seriously the way the problem is being solved? Why isn’t it microelectronics or MEMS? If we can print 3μm OLED pixels surely there’s a way to lift a discrete 1.6mm dot, especially with that huge 2.5mm spacing. Even adjacent dots ought to be no big deal. Maybe a haptic kludge or grid of air pressure nozzles? I have a personal theory of invention that s…
They have a bunch of patents explaining the tech https://www.freepatentsonline.com/20240054912.pdf
The device people say cost 12k does a lot more than just braille so that's not a fair comparison.
Re: Affordable Wheel Based Refreshable Braille Display
#35Considering the human finger is very sensitive to texture perhaps there is a material that change its texture in response to voltage?
Why not just use mechanically decoupled pins that vibrate with a smartphone vibration motor? You don't need texture if the thing vibrates.
Cost and noise would make that extremely unpractical.
Re: Affordable Wheel Based Refreshable Braille Display
#36Earlier quoted context omitted.
I wonder if one could combine a low-fidelity braille display (maybe with heat or vibration (piezoelectricity)) with touch sensitivity and context-sensitive tts in response to touching/reading the display.
I was curious about just temperature. From this pdf[1] it seems fingers have 3-5 cold sensing points per square cm, with cold sensing points being about 10x as prevalent as warm sensing points. So I was thinking about using a combination of a thermoelectric cooler[2] coupled to some thin metal rods, which have individually wound coils around them near the top. The rods would be mounted flush to allow touching all of…
I love unique interface ideas, and this one definitely counts.
What are your thoughts on how to account for the user's fingers heating up the interface rods? I'm imagining someone going back to read a previous character, and their fingers having essentially "reset" the character from body temp.
Re: Affordable Wheel Based Refreshable Braille Display
#37Earlier quoted context omitted.
I was curious about just temperature. From this pdf[1] it seems fingers have 3-5 cold sensing points per square cm, with cold sensing points being about 10x as prevalent as warm sensing points. So I was thinking about using a combination of a thermoelectric cooler[2] coupled to some thin metal rods, which have individually wound coils around them near the top. The rods would be mounted flush to allow touching all of…
I love unique interface ideas, and this one definitely counts. What are your thoughts on how to account for the user's fingers heating up the interface rods? I'm imagining someone going back to read a previous character, and their fingers having essentially "reset" the character from body temp.
This was just off the top of my head, but I imagined the thin rods having low enough thermal mass that the active TEC cooling would not cause fingers to significantly heat up the rods.
That is, the TEC cooler should be able to relatively quickly lower the temperature after the finger is removed.
Again, off the top of my head idea so no idea if it would work or not, but doing a quick viability check should be relatively easy and cheap.
Re: Affordable Wheel Based Refreshable Braille Display
#38A while back I made a (prototype) braille display with a similar concept but using linear sliders (per column) rather than a rotating wheel. Unfortunately I got side-tracked from the project and never figured out the best way to add actuators.
I was proud of the fact that my design could be laser cut from a single sheet and assembled with no glue or fasteners (well, minus whatever mechanism would be needed to actuate the sliders)
Image: https://retr0.id/media/38116918-4023-437b-9a48-d2ffb1d02dbf/...
Short demo video: https://twitter.com/David3141593/status/1639261097252233220 (in the video caption I noted high friction, it was totally fine after sanding)
Re: Affordable Wheel Based Refreshable Braille Display
#39please consider this reference
https://inhabitat.com/ted-moallems-braille-it-labeler-is-mad...
Re: Affordable Wheel Based Refreshable Braille Display
#40Another idea: Instead of actual tactile dots, use a voltage between two appropriately sized/positioned contact points, high enough to be felt by the fingertip, but not so high as to be uncomfortable. Then you just manufacture it as a regular PCB. (It would probably be required to multiplex the voltage between different dots, so that the finger current always flows within the small area of individual dots, rather than…
It might work, and it's an incredibly simple solution, but I'd want to check out if there is any chance of long term nerve damage. The user will be using it many hours a day nearly every day.