JettingPointer: Enabling Skin-to-Pointer Midair Touch Interaction on Minimal Wearables Using Integrated Airflow Haptic Cues MHCI019

We introduce JettingPointer , a skin-to-pointer interaction technique that enables accurate near-surface 2D touch input on minimal wearable devices, such as smart glasses. The core component is an airflow jet, embedded in the glasses frame, that functions as a haptic pointer by providing localized feedback to the finger skin during touch interactions performed above the frame. Users activate functions by aligning their finger phalanx with the airflow stream, guided by proprioception and a distinct point sensation. We optimized the airflow using fluid dynamics principles and characterized the required flow rate for stable tactile perception. In Study 1, we validated its perceptual clarity, confirming that a perceptible point sensation could be reliably achieved within 20 mm of the nozzle. In Study 2, participants performed eyes-free touch tasks with nearly three times greater accuracy when supported by haptic feedback (7.49 mm vs. 21.85 mm error). These findings demonstrate the potential of JettingPointer as a practical method for enabling proprioception-guided, near-surface interaction on compact wearables, with implications for expanding dense input in space-constrained form factors.