Text entry using a foot for severely motor-impaired individuals

Some individuals affected by a motor neuron disease lose voluntary movement of the torso and arms, but keep for some time at least a partial movement of a leg and a foot. This work presents DuoGrapher, a text entry method, and SwingingFoot, an interaction technique, which aim to improve their communication skills by leveraging these motor capabilities. The idea is to attach in one of the user's feet an accelerometer-equipped device, which detect and transmit the movements to a second device located in front of the users' eyes. DuoGrapher interpreted the movements as characters according to the codification being used. Our design is informed by the motor capabilities of a male, in his 60s, with a motor neuron disease. We developed a prototype and tested it with 15 able-bodied users in order to test the usability of the system before doing further studies with motor-impaired individuals. Our goal is understand the challenges of a foot-based system interaction. It became evident that a semi-automatic calibration mechanism and a simpler mapping from movements to character are needed in order to reduce errors.