3D Selection Vault

Nod and Roll

Also known as NR

The user looks at an object and nods to select it, while tilting the head left or right gives commands such as next and previous.

How it works

Eye gaze indicates the object of interest; because the vestibulo-ocular reflex keeps the eyes on it, the head is free to gesture. A nod (downward then upward head acceleration beyond an angular threshold within a time window) selects or activates the gazed object. Head rolls are recognised as roll-and-return, roll-and-stay, or left-then-right sequences, giving seven discrete commands in total (e.g. browsing a gallery of paintings). It was only tried informally (N=8): rated fun, though heavy HMDs made nodding awkward.

Papers