Last Updated on October 26, 2023 by pg@petergamma.org
According to the following comparision table:
| PiEEG 8 (Shield) | Cyton Board (OpenBCI) | HackEEG’s (Shield) | |
|---|---|---|---|
| Signal Processing Interface | Raspberry Pi | Computer | Arduino and computer |
| Analog-Digital Converter (ADC) | ADS1299 | ADS1299 | ADS1299 |
| Channels | 8 | 8 | 8 |
| Transmitter Needed to Read EEG Data | no transmitter needed | Wi-Fi | USB |
| Can Stack with Other Shields? | Yes | No | No |
| Open Source | Yes | Yes | Yes |
| Price (in USD) | $350 | $999 | $495 |
- PiEEG can stack with other shields (taken from crowdsupply PiEEG), but not OpenBCI and HackEE:
https://www.crowdsupply.com/hackerbci/pieeg#products
- Should we choose daisy chain to read out EEG data as Indonesian engineers did it previously:
- But with daisy chain and stacked PiEEGs do we have all EEG channels sampled at exactly the same time? If not some parameters like phase and coherence cannot be calculated.
- But how can we sample all EEG channels at exactly the same time from stacked PiEEG sields? With stacked PiEEGs read out in daisy chain they are not sampled at exactly the same time, they are sampled one after each other.
- Would it require a hardware modification of PiEEG with a buffer to be able ta access all EEG channels at exactly the same time? In theory yes. And we do not know if a Raspberry Pi wo reads out one PiEEG hat after the other is fast enough to get high quality data.
- If we want to build a 32 channel EEG device from PiEEG, should we choose 4 Raspberry Pi’s each one with a PiEEG shield which all sample EEG data at exactly the same time and then send their data to a fifth Raspberry Pi with InfluxDB to join the sensor data from the other four Pi’s? This requires no daisy chain read out, but sensor data should arrive at exaclty the same time at InfluxDB, since the timestamp is given there.
- Or should we choose the following architecture with 32 individual EEG modules instread of PiEEG?
- But does this architecture not require a lot of patience, time and experimenting and is a setup with PiEEG simpler?
- We miss an instruction of Adafruit for all of these devices, but even if it would be there Adafruit cannot deliver to Switzerland anyway.
- Or should we start our projects with an Apple watch and Home Assistant? We can than add sensor data from a Raspberry Pi with PiEEG later on. So we can learn how to handle with Home Assistant and InfluxDB in the example of the Apple watch.
- Or should we follow the foot steps of Scott Harden and start with single components and InfluxDB:
- And develop our own multi-sensor printed circuit board, since a mixed architecture of ADS1299 and InfluxDB is difficult?