Data and code for the metrological characterization of a low-cost wearable brain-computer interface relying on SSVEP.
Data are provided as .mat files. Scripts were implemented in Matlab R2020b, but they could be used with previous versions of Matlab.
Smart glasses data is available for the Epson Moverio BT-200, but also for the Moverio BT-350 and Microsoft Hololens!
The low-cost wearable brain-computer interface operation relies on steady-state visually evoked potentials (SSVEP). This system was implemented with:
- augmented reality glasses Espon Moverio BT-200, used for flickering stimuli (square white icons) presentation;
- electroencephalograph Olimex EEG-SMT with dry electrodes.
These devices were characterized independently of the human user. Hence the uploaded data are related to:
- measures of light intensity associated with the flickering stimuli;
- measures of voltage (microvolts) done with the low-cost electroencephalograph;
The provided code allows to:
- characterize the flickering stimuli in terms of spectral content (amplitude) - see 'BT200_characterization_main.m';
- characterize the low-cost electroencephalograph in terms of linearity and gain error - see 'EEG_SMT_characterization_main.m';
In order to reproduce our results as a starting point for your analyses, you can simply follow these steps:
- download data and scripts (code --> download zip)
- extract zip folder on your PC
- for an example of flickering stimuli characterization, open "BT200_characterization_main.m" in the "BT-200 characterization" folder, and be sure to have the "BT200 frequency scan" subfolder with data (.mat files)
- for an example of electroencephalograph characterization, open "EEG_SMT_characterization_main.m" in the "EEG-SMT characterization" folder, and be sure to have the "frequency scan" and "linearity" subfolders with data (.mat files); the subfolder "sinefit" is provided as well for the sine fitting algorithm needed within the script
- enjoy
- P. Arpaia, L. Callegaro, A. Cultrera, A. Esposito, and M. Ortolano, "Metrological characterization of a low-cost electroencephalograph for wearable neural interfaces in industry 4.0 applications", 2021 IEEE International Workshop on Metrology for Industry 4.0 & IoT (MetroInd4.0&IoT), doi: 10.1109/MetroInd4.0IoT51437.2021.9488445
- A. Cultrera, P. Arpaia, L. Callegaro, A. Esposito, and M. Ortolano, "Smart glasses and visually evoked potentials applications: characterisation of the optical output for different display technologies", MDPI Engineering Proceedings, doi: 10.3390/ecsa-8-11263
- P. Arpaia, L. Callegaro, A. Cultrera, A. Esposito, and M. Ortolano, "Metrological characterization of consumer-grade equipment for wearable brain-computer interfaces and extended reality", IEEE Transactions on Instrumentation and Measurement, doi: 10.1109/TIM.2021.3127650
- "Reactive brain-computer interfaces and augmented reality" project on ResearchGate