Sensitivity at the Edges of the Finger Enables Mixed Reality Force Feedback.

We introduce a new paradigm for rendering high-force sensations by stimulating the edges of the fingerpad rather than the central contact surface. This non-blocking approach preserves natural finger use, enabling simultaneous physical and virtual interactions. To investigate its feasibility, we proposed a mechanotransduction mechanism and conducted biomechanical and psychophysical studies. Our results show that the fingerpad edges are nearly as sensitive as the center under low forces, become roughly 117% more sensitive under moderate forces, and maintain sensitivity at higher forces. The edges also exhibit increased stiffness and tolerate higher forces before discomfort. Furthermore, the left edge exhibited approximately 143% higher sensitivity than the right edge in the right hand. Using these insights, we built a compact wearable device that provides multi-DOF force feedback without blocking the fingerpad and demonstrated its use in VR/AR scenarios. These findings support edge-based stimulation as a viable approach for high-force, scalable haptic feedback in mixed reality and teleoperation systems.