An Open-Source Hardware Acquisition Platform for Physiological Measurements

Abstract

In this article we present a new low-cost physiological signal acquisition platform in compliance with Open-Source Hardware philosophy. The device contains an electrocardiography circuit; two electrodermal activity channels that implement a time-multiplexing technique to remove inter-channel coupling interference; and a skin temperature module. These features make the platform suitable for experiments involving Affective Computing. We have assessed the performance of this device in terms of Signal-to-Noise Ratio (SNR) and Background Noise Level (BNL), an adapted MPEG7 feature for electrocardiography signals. This platform outperforms other commercial devices and most similar state-of-art studies on SNR. Results show values of 11.96, 30.01, 68.40 dB for ECG, EDA and ST, respectively, for SNR, and -28.31 dB for BNL in ECG. Both features were obtained by sampling physiological signals at a frequency of 256 Hz.