An advanced updating increment to speed-up the measurement of AC skin impedance based on a fuzzy inference approach

Conventional methods for determining AC skin impedance with a wide range of frequency process DC to 1 MHz resulting from the off-line estimation are accurate but lack real-time convenience. In the author´s previous proposed methods, the direct measurement is faster than conventional methods because it uses a real-time, on-line measurement and computation, and requires only one high frequency input signal. However, the algorithm to specify the suitable updating value (the defuzzification output multiplied by a gain) in fuzzy inference system is not unique, and the selecting an appropriate updating method for the estimation process of AC skin impedance in fuzzy inference system is necessitated. In order to speed-up measurement, an advanced updating gain, which has a significant effect on the time-performance, is introduced in the real-time analysis of AC skin impedance based on a fuzzy inference system