gait alignment in mobile phone conversations
Conversation partners on mobile phones can align their walking gait without physical proximity or visual feedback. We investigate gait synchronization, measured by accelerometers while users converse via mobile phones. Hilbert transforms are used to infer gait phase angle, and techniques from synchronization theory are used to infer level of alignment. Experimental conditions include the use of vibrotactile feedback to make one conversation partner aware of the other's footsteps. Three modes of interaction are tested: reading a script, discussing a shared image and spontaneous conversation. The vibrotactile feedback loop on its own is sufficient to create synchronization, but there are complex interference effects when users converse spontaneously. Even without vibration crosstalk, synchronisation appeared for long periods in the spontaneous speech condition, indicating that users were aligning their walking behaviour from audible cues alone.
gait alignment alignment synchronization accelerometer mobile devices rhythmic interaction instrumented usability