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

Area of Science:

• Human-Computer Interaction
• Haptics
• Biomechanics

Background:

• Traditional haptic feedback often blocks natural finger use.
• High-force sensation rendering is crucial for immersive mixed reality (MR) and teleoperation.
• Existing methods struggle to provide scalable, high-fidelity force feedback without compromising user interaction.

Purpose of the Study:

• To introduce and validate a new paradigm for high-force haptic feedback using fingerpad edge stimulation.
• To investigate the feasibility of edge-based stimulation for rendering realistic tactile sensations.
• To develop a wearable device for multi-Degree-of-Freedom (DOF) force feedback in VR/AR.

Main Methods:

• Proposed a mechanotransduction mechanism for edge stimulation.
• Conducted biomechanical and psychophysical studies to assess sensitivity and force tolerance.
• Developed and demonstrated a compact wearable device for VR/AR applications.

Main Results:

• Fingerpad edges show comparable sensitivity to the center at low forces, increasing by ~117% at moderate forces.
• Edges exhibit increased stiffness and higher force tolerance before discomfort.
• Significant sensitivity differences were observed between left and right fingerpad edges (e.g., ~143% higher on the left edge of the right hand).

Conclusions:

• Edge-based stimulation is a viable and effective approach for rendering high-force sensations.
• This non-blocking method preserves natural finger interaction, suitable for simultaneous physical and virtual tasks.
• The findings support the development of scalable, high-force haptic feedback systems for MR and teleoperation.