Metrological characterization of a low-cost electroencephalograph for wearable neural interfaces in industry 4.0 applications

In this work, the calibration of a commercial, low-cost electroencephalograph (Olimex EEG-SMT) is presented. Several works report about many wearable neural interfaces based on this device. On the contrary, metrological characterization of this electroencephalograph is lacking. The work reports that preliminary calibration results on this device showed good linearity but also a magnitude error around 8%, with a substantial dependence on frequency. This may lead to incorrect interpretations of the harmonic content of the observed brain-generated electrical potentials. Consequently, for applications based on neural activity monitoring, a metrological calibration of the electroencephalograph is important. Moreover, the proposed calibration method can be adapted to other similar devices.