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Electrotactile Display with Real-Time Impedance Feedback Using Pulse Width Modulation
Second 2012 (vol. 5 no. 2)
pp. 184-188
Hiroyuki Kajimoto, The University of Electro-Communications, Tokyo
An electrotactile display is a tactile interface composed of skin surface electrodes. The use of such a device is limited by the variability of the elicited sensation. One possible solution to this problem is to monitor skin electrical impedance. Previous studies revealed a correlation between impedance and threshold, but did not construct real-time feedback loops. In this study, an electrotactile display was constructed using a 1.45 \mu{\rm s} feedback loop. Real-time pulse width modulation was proposed, and the relationship between skin resistance and absolute threshold was measured to find a function for determining a suitable pulse width from skin resistance. An evaluation experiment revealed that the proposed algorithm suppressed spatial variation and reduced temporal change.

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Index Terms:
Electrotactile display, impedance feedback, pulse width modulation, real-time feedback, two point discrimination.
Hiroyuki Kajimoto, "Electrotactile Display with Real-Time Impedance Feedback Using Pulse Width Modulation," IEEE Transactions on Haptics, vol. 5, no. 2, pp. 184-188, Second 2012, doi:10.1109/TOH.2011.39
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