Development of a Modular Board for EEG Signal Acquisition

Abstract

The increased popularity of brain-computer interfaces (BCIs) has created a new demand for miniaturized and low-cost electroencephalogram (EEG) acquisition devices for entertainment, rehabilitation, and scientific needs. The lack of scientific analysis for such system design, modularity, and unified validation tends to suppress progress in this field and limit supply for new low-cost device availability. To eliminate this problem, this paper presents the design and evaluation of a compact, modular, battery powered, conventional EEG signal acquisition board based on an ADS1298 analog front-end chip. The introduction of this novel, vertically stackable board allows the EEG scaling problem to be solved by effectively reconfiguring hardware for small or more demanding applications. The ability to capture 16 to 64 EEG channels at sample rates from 250 Hz to 1000 Hz and to transfer raw EEG signal over a Bluetooth or Wi-Fi interface was implemented. Furthermore, simple but effective assessment techniques were used for system evaluation. While conducted tests confirm the validity of the system against official datasheet specifications and for real-world applications, the proposed quality verification methods can be further employed for analyzing other similar EEG devices in the future. With 6.59 microvolts peak-to-peak input referred noise and a −97 dB common mode rejection ratio in 0-70 Hz band, the proposed design can be qualified as a low-cost precision cEEG research device.

A feasibility study of a complete low-cost consumer-grade brain-computer interface system

“…Different affordable consumer-grade EEG devices have appeared in both Academia (e.g. [5,6,7,8]) and the market (e.g. B-Alert X10, Neu-roSky, OpenBCI, Emotiv), offering different alternatives from easy-tomount electrode systems to low-cost amplifiers.…”

Development of an Ultra Low-Cost SSVEP-based BCI Device for Real-Time On-Device Decoding

“…Uktveris et al demonstrated a very promising device with wireless capabilities (communication with a host device using Bluetooth Low Energy (BLE) and/or Wi-Fi) and some on-device digital signal processing ability [11]. However, their device requires final signal decoding to be performed on a host device separate from the actual BCI itself.…”

Low-cost brain computer interface for everyday use

“…Tyler et al (2015) also described the development of a device for reading EEG signals, however, there is no information about the manufacturer of the components, the layout of the printed circuit board, or the PCB board characteristics. In a paper that addressed similar issues as we examine here, Uktveris and Jusas (2018) considered both ADS1299 and the ADS1288 ADCs. The board presented in their work had only the standard implementation recommended by the manufacturer for the ADC, one aimed at the Arduino market as an additional shield for the MEGA2560 models.…”