Touch and type interfaces for the blind

Estimated reading time: Less than 5 minutes

Since the last few months, I’ve been seeing some new User Interfaces popping up to enable the blind and the visually impaired people to type on a touch base smartphone device.

Here are the latest series and my opinions about them.

1) Touch Screen Braille Writer

The First one is the ‘Touch Screen Braille Writer’ developed by NMSU undergraduate Adam Duran, Stanford Assistant Professor Adrian Lew, and Stanford Doctoral candidate Sohan Dharmaraja (Source: Gizmodo). Check out the demo video below.

The application is interesting and quite robust. The UI however is designed for the bigger screen and the same interface can not be ported to a smaller screen device such as an iPhone or and android smartphone device.

2) BrailleType

The second one is “BrailleType” designed and developed by Ankit Daftery. Check out the demo video for BrailleType Beta 2.

Although Ankit has made significant improvements from the Beta 1, there are some certain points that I’m concern about BrailleType.

1) Scaling:
As far as I can see from the video there is no way one can easily find out the accurate location of each dots. For instance if I want to type the letter ‘b’ which is to tap on dot 1 and dot 2, after tapping dot 1, how do you know how far your finger has to move down to tap on dot 2?

2) Movements:
To type ‘a’, you tap once on dot 1. To type ‘y’, you have to tap on dot 1, then dot 3, then dot 4, then dot 5, then dot 6. How many taps was that? 5 taps. This is a lot of work to type just a single letter, and this will significantly reduce the typing speed.

3) Timing:
What is the time factor within which you’ve to tap all the dots to type a particular letter? To type ‘a’, you tap of dot 1. To type ‘b’ you tap on dot 1, then pause, then tap on dot 2. How long can one pause between the taps? Is the default timing convenient for every user? I doubt it would be unless it can not adapt automatically according to the user behavior.

4) Screen size:
BrailleType is developed for android devices; Android devices are made by various manufacturers and screen sizes vary widely: from a big screen size Android device to a much smaller size one. How well would BrailleType app adapt to that? How is the scaling factor (distance between dots) on a smaller size as compared to a bigger size. Suppose if I’ve been using a bigger screen android device for a whole year and just changed the device to a smaller size screen, would I be still able to type that fluently?

3) Braille Touch

The third one, which came out just today is the BrailleTouch app developed by researchers at Georgia Tech.

Braille Touch app has several advantages over Ankit Daftery’s BrailleType. It addresses some of the questions I addressed with regards to BrailleType’s design.

1) Scaling:
Since Braille Touch uses Multi-Touch feature, as you can see from the video above, all the fingers are already in position once a user holds the device. So scaling is not an issue here.

2) Movements:
For each letter, technically we can consider here as just one tap. A user touches all the dots  for a letter at one time, which means the speed of typing will improve significantly as compared to Ankit Daftery’s BrailleType. If I’m not much mistaken, BrailleType did implement multi-touch in beta one but it discontinued using it.

3) Screen size:
The screen size issue is still prevalent however since both your hands are holding the device, it’d be quite easier to detect the scaling of the dots and once a user is in position, since each finger is assigned to each dot, there is not much movements to  be made so the probability of error is reduced upto certain extent.

4) Swipe Type

Finally, we have Swipe Type, a concept UI I’ve developed myself. Here’s the demo

All of the above UI has one thing in common: all uses both hands.

My question is, why do one always have to use two hands to type?

Swipe Type’s Circular Keypad enable to type a letter in one stroke or swipe

Many probably do not see it as an issue but I think it is. With Swipe Type, I’m trying to address it and to improve the overall experience. Swipe Type uses gestures instead of taps. Since the keypad is designed in such a way that one can type any letter that can be represented by the Braille System in one stroke or swipe, one do not need to worry much about the scaling or do not have to worry about lifting the fingers and making sure that it doesn’t touch when not meant to.  The major advantage of Swipe Type is you need only your thumb to type (great disadvantage if you don’t have a thumb!). It also leaves a lot of screen area for your finger to rest (any part outside the circular keypad is inactive).

Anyway, all of these are really interesting and I certainly do hope that soon enough, visually impaired people and the blind can benefit from these technologies and UIs.

If you’ve any inputs or thought you would like to share, share it in the comment.

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  1. There are many other interfaces. Please check and include into your analysis:

    BrailleTye – Tiago Guerreiro – one tap at a time

    TypeInBraille – Sergio Mascetti – two taps at a time – a row

    Perkinput – Shiri Azenkot – three taps at a time – a column

    SmartBraille – ??? – swipes and taps – ?

    Radisbruder at youtube – Braille Dynamic Virtual Keyboard – six taps at a time – the full braille cell, just like BrailleTouch, but no user studies and published later than the first publication of BrailleTouch in July 2011.

    •  @marfeote 
      Thanks for the list!
      Just wanted to point out that Perkinput can be used with one *or* two hands (entering one or both columns of the braille cell at a time). The important distinction with Perkinput is that there are no soft keys that correspond to dots — the system infers which fingers contact the screen based on user-set calibration points.

  2. Hi Ptam,

    Nice idea with thumb swiping on your Swipe Type! The difficulty that I see so far for most of the solutions above is that it’s hard to keep the fingers at the right place, since there’s no physical feedback to the user. I think Braile Touch gives a better way to keep the fingers at the right place.

    One more thing, may I know how blind users will know that they have activate the interface on Swipe Type?




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