Abstract
Purpose. The main objective of this article is to present an alternative method of interacting with a computer which empowers persons with very severe motor impairments to leverage retained capabilities in order to independently control parts of their daily lives. The input strategy is based on tiny intentional contractions of a single muscle of choice (requiring a minimum of physical contribution only) which are used as selection markers in the context of scanning.
Method. To demonstrate the usefulness of the idea, two applications (combined in a single software system) have been implemented (initially): a module turning the PC into a Universal Remote Control and a Text-To-Speech module. The system has finally been supplemented by a third application offering to effortlessly make telephone calls.
Results. A simple experiment requesting the speed of the scanning scheme shows that the theoretical concept really works. Furthermore, the usability by novice users from the target population is proven in a user study focusing on the telephony application.
Conclusions. It is concluded that the approach has a large potential for persons with severe physical disabilities, meaning that the resulting system is indeed able to improve its users' quality of life.
Acknowledgements
This work is partially supported by DFG grant FE 936/3-2 ‘The AID package – An Alternative Input Device based on intentional muscle contractions’.
Notes
1. This step is supposed to be done by an able-bodied caregiver.
2. It should be noted that the first keyboard row requires (1 + 1/2)·τ, since the ‘OK/Cancel row’ is actually scanned before.