AAC Shim

AAC Shim is a simple helper method for helping web apps that want to support being embedded inside an AAC system.

Demos | Shim Testing Tool | GitHub

What is AAC?

AAC stands for Augmentative and Alternative Communication. It's a broad term that includes anything that supplements or replaces verbal communication, but many people use it to specifically refer to speech-generating tools that run on a computer or tablet. If someone can't speak or struggles to speak on their own, whether because of a disability, surgery or temporary issue, they can tap out messages and hit a button to have a device speak for them. It's actually super cool.

If the individual is literate and has good control of their hands they could just type out their messages with a keyboard. But for a lot of communicators that's asking too much, so they can instead use buttons with pictures or common phrases to make things easier or faster. Again, super cool.

You probably envisioned someone tapping away on a tablet during that description of AAC, but that's actually only one method of access. Some users can't move their hands that well or at all, but they can still blink, or swallow, or move their eyes, or trigger a single muscle, or even just initiate some brain activity. Any of those actions can be picked up by a range of different devices and interpreted as a selection by the user. If you aren't freaking out right now about how amazing technology is then you should probably give yourself a minute to do so.

But if you're a web developer, you're also thinking about how insanely painful it would be to have to support all of those different selection techniques. The good (scary?) news is that someone is probably actually already using alternative access tools to navigate your site. A lot of the hardware actually comes with mouse emulators and such so you don't have to do a whole lot other than, you know, support accessibility standards.

Why AAC-Enable my Page?

Some users have high enough functionality that they can navigate between web sites, load apps, minimize windows, etc. But for some users, their primary access method is their AAC interface. If they want to, say, control their smart home, or play an educational game, or read a book, or Skype with their friends, they do it all from within their AAC interface. Traditionally all that functionality had to be hard-coded into the AAC app itself, but if you've ever tracked the moving target of a modern web API then you know how sucky that prospect sounds.

So! Instead we're pushing a new strategy, where web apps can build in their own support for AAC users and (along with some offline caching) more extensibly offer support for individuals who use their AAC system as the primary channel to the online world.

Honestly most of the first-generation of AAC-enabled web apps will probably be written as shims of their own, simplified interfaces to more complicated systems like SmartThings, Facebook, YouTube, GoodReads, Fandango, etc. But that's ok, we still want to make those easier to build so we can help people out!

How to Use AAC Shim

Include the shim in your page, then

    aac_shim.status(function(result) {
      if(result.status == 'ready') {

^ That's the easiest level of integration. It will take any "hover" events, whether they're done by a mouse or eye tracker or head mouse or whatever, and trigger them as standard mousemove events. It'll also map any taps, touches, clicks, or other selections to standard click events for you.

Different AAC systems may work differently, so make sure to wait for a status response of ready before making any other calls to AAC Shim.

Defining Targets

Targets are regions on the screen that you want to make accessible to the user. The user can always hover or click anywhere in your frame and you can receive the event, but you can also define specific regional targets. Here's why you would do that:

Having the whole frame as a large region for selection is nice and flexible, but it can make it harder for the user to know what they're supposed to do. Some users only have enough control to essentially hit a single button, so the AAC interface may "scan" through all the available targets, drawing a highlighted box around each target, one at a time. Or if the user is driving the mouse cursor via eye gaze or head movements, often selection occurs by "holding still" or "dwelling" on the same spot for a period of time. Defining targets helps the system know the user is dwelling on a target even if there's some movement.

Anyway, here's how to define targets:

      id: 'my_target' // if you don't define one, the shim will for you
      left: 50, // pixels
      top: 50, // or you set as a percent "10%"
      width: 150,
      height: 150,
      prompt: "bacon", // this is an auditory prompt given to users with vision or processing issues
    }, function(result) {
      // called whenever the target is selected

You can also clear_target to clear one at a time, by id, or clear_targets to clear them all at once.