Mathematical Model of Fingertip Skin Under Constant-Current Electrotactile Stimulation

Due to low energy consumption and fast response, electrotactile feedback has shown great potential in human machine interaction. However, regulating electrotactile perception remains challenging because of the high variability of electrode skin impedance. Electrode-skin modelling is a common solution, but current researches are still facing many problems such as non linearity. This paper focuses on voltage response modelling based on data-driven analysis. Two experiments targeting fingertips have been conducted. Significant correlations between pulse amplitude (PA), pulse width (PW) and peak voltage (V-peak) (R-2 > 0.99) have been found. A mathematical model of fingertip skin is then derived, which enables a precision fitting of the voltage response (RMSE=0.9%). Finally, two calibration methods are proposed for peak voltage prediction. The accuracy (RMSE=2.5%) is also verified under different electrode-skin conditions. The results of this paper are expected to provide novel theoretical support for precise regulation of fingertip electrotactile perception.

Automated summary

Due to its low energy consumption and fast response, electrotactile feedback has the potential for great use in human-machine interaction. However, the regulation of electrotactile perception remains challenging due to the variability of electrode skin impedance. This paper focuses on voltage response modelling using data-driven analysis, successfully obtaining a mathematical model for fingertip skin and proposing calibration methods for peak voltage prediction. The results provide novel theoretical support for precise regulation of fingertip electrotactile perception.