Presentation of Finger-size Shapes by Combining Force Feedback and Electro-tactile Stimulation

In virtual environments, rapid and accurate perception of object shapes is critical for achieving skillful interactions and enhancing immersion. Typically, conventional force feedback devices that provide force direction and magnitude across the entire finger faces challenges in accurately representing fine geometric details of object shapes, such as edges. To address this issue, we augmented force feedback devices with a compact and high-density cutaneous electrical stimulation mechanism, aiming to improve the representation of subtle shapes. In the evaluation experiments, reactive force and edge cues for virtual objects were simultaneously presented, and shape discrimination tests were conducted on four types of column shapes with a thickness of 7.5 mm. Comparing force feedback-only, cutaneous feedback-only, and their combination conditions, our results demonstrated that the combined approach improved shape discrimination accuracy, confirming a more precise perception of fine geometric details.