Scanning Ambiguous Keyboard (SAK)

I. Scott MacKenzie
Dept. of Electrical Engineering and Computer Science
York University
Toronto, Ontario, Canada M3J 1P3


Last update: 23/10/2017



There is a long history of research in accessible computing on text entry using single-switch scanning.  There is also a long history of research in human-factors and HCI on text entry using ambiguous keyboards.  See the "design space" figure below.


An interesting possibility is to consider an input method that combines the central features of single-switch scanning and ambiguous keyboards. See the modified design space below.


The result is a Scanning Ambiguous Keyboard (SAK).  The design details are complex, since decisions must be made on the number of keys, the letter-to-key assignments, the scanning pattern, and so on.  Details of an initial design, an implementation, and an evaluation of a scanning ambiguous keyboard (SAK) are found in the following two references:

Follow-on implementations and evaluations using eye blinks and other methods for input are found in the following references:

A key purpose of this research note is host a download site for the SAK software.  The download is a zip file containing the Java source and class files, as well as the API, related text files, image files, etc.  A good way to get started is to unzip all the files into a directory and then open SAKExperiment.html in a browser and read the API.

The software in the zip file was used for the experiment described in the first two papers above.  The software for the eye-blink implementation was mostly the same.  Modifications are described in the papers.

If you have any problems, questions, or comments, please let me know.

Good luck,

Scott MacKenzie (mack "at"

P.S. Click here to access additional software for conducting HCI user studies.