Perceptual Properties of Fingertips Under Electrotactile Stimulation

To sense and represent electrotactile perceptual properties is a crucial milestone in order to achieve intuitive haptics. However, electrotactile perceptual properties are very poorly studied. This study presented an experimental study on the electrotactile perceptual properties of fingertips. A series of experimental paradigms were designed based on self-designed hardware and psychophysical evaluation methods. The detection threshold (DT), pain threshold (PT), just-noticed difference (JND), intensity-quality characteristics and multi-level discrimination ability for pulse amplitude (PA), pulse width (PW) and pulse frequency (PF) have been explored. The experiments verified the individual differences in DT and PT and found that the fingertips were more sensitive to PA and thus more valuable for information encoding. In discrete coding, the recognition accuracy decreases with increasing number of levels, preferably less than 4. The results are expected to provide valuable suggestions for the parameter coding of electrotactile information presentation.