https://audioboom.com/posts/5655817-the-first-braille-smartw...
They include interviews with blind people who've tried it.
They say that it's smaller, lighter, and cheaper because they use a new type of actuator that isn't "on a ceramic substrate".
The company plans to ship its first 150,000 devices by the end of the year for £300; the dot mini is an educational braille reader planned for sale for £650.
Here's a mashable link saying the product is shipping: http://mashable.com/2017/02/22/dot-smartwatch-retails/#c8Hyx...
That means nothing. Modern actuators are piezo-electric. I have no idea what "ceramic substrate" they are talking about.
The mashable link is just a press kit.
I don't know what is in the RNIB podcast, because the audio is not available to me.
The piezo crystals are the ceramic. This new device claims not to use piezo crystals, and that's why it's smaller.
There's a possibility it's using electroactive polymers in a closed bubble together with latches. This would be much cheaper than piezo systems, and also smaller.
N. Di Spigna, P. Chakraborti, D. Winick, P. Yang, T. Ghosh and P. Franzon, “The Integration of Novel EAPBased Braille Cells for Use in a Refreshable Tactile Display,” Proceedings of the 12th International Conference on Electroactive Polymer Actuators and Devices, San Diego, March 2010, p. 9.
Nothing extra.
- is smal, ideally the distance between Braille dots or about (distance within a character is smaller than that between dots in different characters) 2.5 mm by 2.5 mm, with a height of less than 2cm or so,
- can lift a dot by about 1mm (from definitely not above the surface to 0.9mm above it),
- withstands a force of about .3N (30 grams),
- can be switched while the user exerts that 30 gram force on it,
- will work for 10^6 actuations,
- works reliably in the presence of dirt, grease and human sweat,
- doesn't require enormous amounts of power (piezo-electric Braille cells only need power when switching),
- is safe when users (almost) touch them with their bare fingers (piezo-electric cells use 200V or so to switch, but that is at a few cm from the Braille pins),
- can be produced for a few dollars (you need 8 for a Braille cell or 160 for a 20-character display, so it adds up). If your goal is to make a full page (say 8000 pins) $1 each already is too much.
You also wil like want to switch 500 of these in 0.1s or so.
Especially if you forget about the desired reliability and/or limit the force or the travel, the problem gets a lot easier.
I think the videos that these guys posted are real, but wonder how long this device will keep working.
To some extent, the current technology, which is called a piezoelectric display is like a lithium ion battery. Its not like we don't have other battery technologies, it is just that lithium is enough better than the others, that no other can take hold. The piezo displays are almost silent, last a LONG time (20 years), and take very little power. They are, however, slow and bulky and not practical for mobile applications. The mechanism is so large, you cannot create a multi-row display. (edit: they are also rediculously expensive!)
There have been multirow displays using solenoid actuators. These were hand made by grad students and weighed a ton. They used a huge amount of power and got jammed easilly. Other than that, there are pneumatic displays with huge potential, but are also bulky. There are static electric displays that have life expectancy issues, and a few other technologies, like using memory springs, that tend to have speed issues. Then there are a huge number of mechanical "conveyor belt displays" which are too noisy to use in a classroom or office.
But all of the displays you see being publisized are not the ones that I am talking about. Displays like the one you linked to are totally 100% FAKE!!!
https://nfb.org/images/nfb/publications/bm/bm00/bm0001/bm000...
Impractical: you can stack piezo-electric Braille cells, but your device will be about half an inch high per line of text. Weight also goes up, of course.
Not affordable: ballpark, a _cheap_ piezoelectric Braille cell costs at least $25 per character (http://www.aph.org/orbit-reader-20/ uses a different technology, but is considered cheap at $500 for 20 characters). That's $3.50 per 'bit'. At that price, two 80-character lines would cost you $4000 (In reality, that probably buys you _one_ 80-character line)