Design and Evaluation of a 6-DoF Wearable Fingertip Device for Haptic Shape Rendering.

Area of Science:

• Haptic Technology
• Human-Computer Interaction
• Robotics

Background:

• Virtual objects require richer haptic feedback for realistic interaction.
• Existing wearable fingertip devices lack sufficient degrees of freedom (DoFs) to convey complex shape features.

Purpose of the Study:

• To design and evaluate a 6-DoF wearable fingertip device (WFD) for displaying virtual object shape features through curvature.
• To assess the WFD's performance in curvature perception and shape recognition tasks.

Main Methods:

• Designed a 6-DoF wearable fingertip device (WFD) utilizing a Stewart parallel mechanism with six miniature servo motors.
• Analyzed and validated the kinematic model and tested the force output capability of the WFD.
• Conducted subjective perception experiments with 15 adults to evaluate curvature identification and shape recognition accuracy.

Main Results:

• The WFD achieved a just noticeable difference (JND) of 3.02±0.23 m⁻¹ for curvature identification.
• 6-DoF haptic feedback from the WFD improved curved surface recognition accuracy from 53.4±7.1% (3-DoF) to 72.0±5.9%.
• Shape recognition accuracy reached 82.3±8.2% without visual feedback when using the WFD with a Touch device.

Conclusions:

• The 6-DoF wearable fingertip device demonstrates effective performance in conveying haptic sensations for virtual object shape display.
• The WFD shows significant potential for enhancing user experience and accuracy in virtual reality and haptic applications.
• The device's ability to improve shape recognition, even without visual cues, highlights its efficacy in tactile perception.