PhD Student


Bitey: An Exploration of Tooth Click Gestures for User Interface Control


We present Bitey, a subtle, wearable device for enabling input via tooth clicks. Based on a bone-conduction microphone worn just above the ears, Bitey recognizes the click sounds from up to five different pairs of teeth, allowing fully hands- free interface control. We explore the space of tooth input and show that Bitey allows for a high degree of accuracy in distinguishing between different tooth clicks, with up to 94% accuracy under laboratory conditions for five different tooth pairs. Finally, we illustrate Bitey’s potential through two demonstration applications: a list navigation and selection interface and a keyboard input method.


Teeth Occlussions

The first and third row of images show gnathosonograms produced by tooth clicks (x-axis seconds) while the second and forth row illustrate the corresponding normalized FFTs (x-axis Hz). Images on the left present single clicks while images on the right illustrate multiple clicks overlaid.



To explore the limits of what Bitey can accomplish, we implemented BiteWrite, a tooth-click based text input system. We used a version of MacKenzie’s H4-Writer, using Huffman codes to assign minimal click sequences to generate letters. For example, two clicks—represented as 0 and 1—generate sequences such as ‘010’ for ‘e’ and ‘011001’ for ‘g’. For a participant able to click N pairs of teeth, we implemented the N − 1-click version of the keyboard, with theNth click used as “cancel” (in the case of a partially entered sequence) or “backspace” (otherwise).

Full Citation

Daniel Ashbrook, Carlos E. Tejada, Dhwanit Mehta, Anthony Jiminez, Goudam Muralitharam, Sangeeta Gajendra, Ross Tallents. Bitey: An Exploration of Tooth Click Gestures for Hands-Free User Interface Control. In ACM 18th International Conference on Human-Computer Interaction with Mobile Devices and Services (Mobile- HCI), Florence, Italy, 2016, 12 pages (23.9% acceptance rate).