Electrodes Placement Investigation for Hand Gesture Recognition Based on Impedance Measurement

Impedance spectroscopy is a popular analytical tool in materials research that provides a variety of information through precise analysis. Experimentally obtained data is analyzing using a mathematical model based-physical theory to predict theoretical impedance or a relatively empirical equivalent circuit. One major reproducibility problem relating to the placement of the electrodes should be investigated. This paper presents a study for the optimal electrodes positioning for accurate data in EIM. The measurements were carried out on the flexor muscles of the right forearm on a group of three healthy male subjects of the same age approximately. In order to reach a maximum distinguish between three chosen gestures(Open Hand, Closed Hand, and V Sign), a comparison study was carried out for different electrode inter-distance starting from 5 cm, 5.5 cm, and 6 cm with excitation current of 0,1 mA. The optimal inter-electrodes distance was defined experimentally by evaluating the relative change of real and imaginary parts ΔR and ΔX of the measured impedance in the frequency range between 1 kHz and 10 MHz.