We introduce an alternative paradigm for rendering high-force sensations to the fingertip by stimulating the edges of the fingerpad rather than the bare finger. This non-blocking approach enables virtual and augmented touch while preserving natural finger use, allowing simultaneous digital and physical haptic interactions. To explore this concept, we developed a plausible mechanotransduction working principle, conducted biomechanical and psychophysical experiments, and built a small wearable prototype device. Our findings suggest that the finger’s edges are nearly as sensitive as the center for low forces (0.7 N), are about 150% as sensitive to moderate forces (1 to 3 N), and exhibit extended sensitivity at high forces (up to 5 N). Additionally, edge regions show nearly 140$%of the stiffness of the center, and are capable of tolerating higher forces before participants report discomfort. These results support the viability of edges-based stimulation for nuanced, high-force haptic feedback, which could have implications for mixed reality and tele-operated interactive systems.

Authors: Jung-Hwan Youn, Ali Israr, Craig Shultz

Jung-Hwan Youn, Ali Israr, and Craig Shultz. 2025. Pushing the Boundary: Force Sensitivity at the Edges of the Finger for Mixed Reality Haptics. In IEEE World Haptics Conference (WHC ’25), 2025, Suwon, South Korea.