The Impact of Gaze and Hand Gesture Complexity on Gaze-Pinch Interaction Performances

This paper investigates user performance and gaze-hand coordination errors in gaze-pinch interaction across different task complexities involving gaze and hand gestures. We designed gaze-based single target pointing tasks with varying levels of gaze complexity: simple target, target with a visual cue, and target requiring visual search. Hand gesture complexity included simple thumb-index pinch and multi-finger pinching gestures (thumb-index, thumb-middle, thumb-ring). Our findings reveal that gaze-pinch coordination errors predominantly occur due to late triggering, where the gaze shifts away from the target before pinching begins. While hand gesture complexity did not significantly affect error rates, tasks requiring additional visual attention, like target recognition or visual search, increased gaze-pinch error rates. The study also highlights the impact of individual differences on gaze-hand coordination during interactive tasks. These individual differences underscore the need for personalized approaches in designing gaze-hand interaction systems that cater to diverse user profiles. Future work aims to address these challenges with larger participant groups and further explore factors influencing gaze-hand coordination in interactive systems.