Maker Ildar Rakhmatulin is working to make entry-level brain-computer interfaces affordable and easy to build, designing an open source add-on for the Raspberry Pi family of single-board computers to interface with electroencephalograph sensors: the PIEEG.
"This project is the result of several years of work on the development of BCI [Brain-Computer Interfaces]," Rakhmatulin explains. "We believe that the easiest way to get started with bio-signals is to use a shield."
That's exactly what Rakhmatulin has designed: A board which connects to the general-purpose input/output (GPIO) header of a Raspberry Pi single-board computer and acts as an interface to a head-worn EEG sensor — picking up the minute electrical signals of brain activity and amplifying them for processing on the device.
In theory, the process is simple - but there are a few gotchas. For starters, the Raspberry Pi must be entirely isolated from mains power — meaning you have to run it from a battery, and use a display which is in turn powered by the Raspberry Pi or via a battery. For the best signal, you also have to wear insulated shoes — and real-time readings need a mix of C/C++ for reading the sensors and Python for processing and visualization.
At the same time as the Raspberry Pi add-on, Rakhmatulin is working on bringing the same capabilities to the NVIDIA Jetson Nano range — using a specially-shaped PCB to work around the heatsink which keeps the board's system-on-module cool.
Source code for the project is available on Rakhmatulin's GitHub repository, though promised design files for the hardware have not yet been uploaded — and the whole thing is very clearly marked as a work-in-progress.