Force Rendering via Electrical Stimulation of Fingernail and Finger Pad

Previous neurophysiological studies have revealed that the strain around the nails significantly contributes to the perception of force at the fingertips. Based on this finding, this study presents a novel method for achieving multi-degree-of-freedom force presentation. The proposed approach applies electro-tactile stimulation to the entire fingertip, including its lateral sides. The effectiveness of the proposed method was evaluated through two experiments. Experiment 1 assessed whether force perception was present in three degrees of freedom-front-back, up-down, and left-right-using electrical stimulation. Experiment 2 investigated the role of electrical stimulation around the fingernail in contributing to force perception. The results suggest that the proposed method facilitates multi-degree-of-freedom force perception. Furthermore, electrical stimulation around the fingernail was identified as a crucial factor in producing force sensation.