Abstract:Nowadays, haptics has been widely used in many fields such as telecontrol robots, surgical robots, prosthesis, entertainment interface and virtual reality, which has improved the operability of actual or virtual objects for human. Electrotactile stimulation is a main technique to reproduce tactile sensation by changing the frequency, duration, amplitude, direction and distribution of constantcurrent electrical pulses. In this article, a model of cutaneous nerves under electrical stimulation was developed to serve for simulation study, and stimulation function was deduced based on the model. With the simulation, optimal paradigms for stimulating three mechanoreceptors (Meissner’s corpuscle, Merkel’s disc and Pancinian corpuscle) were separately found in a trialanderror way, i.e. by changing the direction and amplitude of electrical pulses in arrays through simulation study. Furthermore, psychophysical experiments were carried out to make 10 experimenters sense two kinds of feelings (vibration and pressure). The targeting area for electrotactile stimulation was on the index fingers. For vibration feeling, positive electrical pulses of different frequencies(10,30,70,90 Hz)were applied; For pressure feeling, negative electrical pulses of different widths(150、200、250、300 μs)were applied. The subjects gave their subjective judgment on the grade of the feeling generated by electrical stimulation.Statistical results showed that the averaged recognition rate of two sensations under the help of the model reached higher than 80%. The model is helpful in finding the best stimulation pattern and assuring the realization of optimal reproduction of tactile sensation.
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