Keep or wave? Evaluating static and dynamic gestures across in-vehicle function-control tasks.

Mid-air gesture interaction is a promising input modality for in-vehicle information systems, but the relative suitability of static and dynamic gestures across vehicle functions remains unclear. Thirty-three licenced drivers completed a within-subject driving-simulator experiment involving nine in-vehicle function-control tasks. Vehicle-control stability, hand-off-wheel duration, gesture-execution fidelity, and subjective user experience were assessed, and linear mixed-effects models examined gesture type, task, and their interaction. Gesture type did not significantly affect longitudinal- or lateral-control stability. However, static gestures produced shorter hand-off-wheel durations, higher execution fidelity, and more favourable ratings of perceived validity, satisfaction, perceived safety, and learnability. Significant gesture type × task interactions emerged for interaction performance and all user-experience dimensions. Static gestures performed relatively consistently across tasks, whereas dynamic gestures were more task dependent. These findings suggest that the evaluated static gestures may serve as more robust candidates, whereas dynamic gestures should be selected according to task-specific gesture-command compatibility.