Preserving Real-World Finger Dexterity Using a Lightweight Fingertip Haptic Device for Virtual Dexterous Manipulation

TL;DR

A lightweight, wearable fingertip haptic device that provides physics-based haptic feedback for dexterous manipulation in virtual environments without hindering real-world interactions is presented, and it is demonstrated that participants can perceive and respond to pressure and vibration feedback.

Abstract

This study presents a lightweight, wearable fingertip haptic device that provides physics-based haptic feedback for dexterous manipulation in virtual environments without hindering real-world interactions. The device's design utilizes thin strings and actuators attached to the fingernails, minimizing the weight (1.76g each finger) while preserving finger flexibility. Multiple types of haptic feedback are simulated by integrating the software with a physics engine. Experiments evaluate the device's performance in pressure perception, slip feedback, and typical dexterous manipulation tasks. and daily operations, while subjective assessments gather user experiences. Results demonstrate that participants can perceive and respond to pressure and vibration feedback. These limited haptic cues are crucial as they significantly enhance efficiency in virtual dexterous manipulation tasks. The device's ability to preserve tactile sensations and minimize hindrance to real-world operations is a key advantage over glove-type haptic devices. This research offers a potential solution for designing haptic interfaces that balance lightweight, haptic feedback for dexterous manipulation and daily wearability.

Figures (14)

• Figure 1: The fingertip haptic device is designed to be worn on the fingernail, providing haptic feedback through a thin string driven by a motor. This design keeps the pad of the fingertip unobstructed, allowing the user to feel real objects while receiving haptic sensations. The device weighs 3.57g for the thumb and 1.76g for the other fingers.
• Figure 2: a) A sample physics-based dexterous manipulation scene where participants can perform tasks such as stacking objects, placing objects in holes, and sliding objects. b) The virtual hand is composed of virtual couplings, with the force output proportional to the penetration depth of the real hand's position(in green). The measured phalanges and phalanges in the physics engine are connected by virtual springs. Also, adjacent phalanges are connected by ball joints. c) In the fingertip pressure perception experiment, participants were asked to grasp an object and find the smallest grasp force that would not cause the object to drop. d) The "Re-Grasp" experiment. participants were asked to slide an object and re-grasp it before it fell to the ground. e) Peg-in-hole, a typical dexterous manipulation task, requires participants to insert the object into a designated hole.
• Figure 3: The schematic diagram illustrates the information flow and main components of the system.
• Figure 4: The hardware components are mounted on the fingertip, with the shell adhered to the fingernail for stability. The device has a weight of 3.57 grams to the thumb's fingertip and 1.76 grams to each of the other fingertips.
• Figure 5: a): Measuring the pulling force of the motor using a force sensor, the clamp fixed the system to decrease vibration. b): Comparing the shapes of coreless motors for the thumb and other fingers; 612 denotes a diameter of 6mm and a length of 12mm, while 716 indicates a diameter of 7mm and a length of 16mm.