In this research, we consider an alternative input method that is far more accessible and expressive than buttons. Rather than using small buttons specially integrated into headphone cords, one could appropriate the entire cord as the input device. Cords are particularly appropriate because they are often external and have a large surface area. Furthermore, while buttons provide primarily binary input, a cord could potentially provide continuous input along at least four dimensions (twist, touch location, and bend).

These four potentially continuous input dimensions a cord provides enable a wide range of applications. In addition to providing navigation and controls for audio players and other mobile devices, a cord could be used as a joystick to play eyes-free games on mobile devices. This cord could also be integrated into clothing to control devices or measure motion, and into everyday items such as backpacks and lampshades. Finally, an array of these cords could be woven into a cloth to detect how it is being manipulated.

To explore these interactions, we built a prototype cord that senses how hard it is being pulled, how much it is being twisted, and where it is touched. It is also possible to include bend as a fourth, independent dimension, but we leave this to future work. Our cord is not only far more expressive than a button; it is also easy to access, eyes-free, and unobtrusive.

Research Team: Julia Schwarz, Chris Harrison, Scott Hudson, and Jennifer Mankoff