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joshbrew / HEG_ESP32

HEGduino with ESP32: Hemoencephalography meets highly affordable IoT!
https://hegalpha.com
MIT License
83 stars 25 forks source link

Hardware design files missing #3

Open dumblob opened 4 years ago

dumblob commented 4 years ago

First of all thanks for your endeavor - I find it useful and interesting.

It seems though the original design files of the current HW revisions are missing (.brd files?). There are some todo lists speaking of issues with signal/noise ratio. Maybe there'll be some knowledgeable people around to spend few hours with improving or at least evaluating the designs once they'll be available.

When do you plan to release them (you can release also some drafts etc. - not necessarily the final perfectly tuned design if it doesn't exist yet)?

Also, looking at https://github.com/moothyknight/HEG_ESP32/tree/master/Software/hardware/boards I'm a bit puzzled what are the individual folders about as I'd naturally expect to see two PCBs (judging based on your Crowdsupply campaign), but several different subfolder with varying amounts of exported data files are available.

Could you maybe also clarify what is what and how newcomers shall read the data to get a glimpse how it all fits together? I mean not technical details about the PCBs or whatever, but rather the structure of this project repository :wink:.

Thanks and keep going!

joshbrew commented 4 years ago

@dumblob

Hey there, I think the only brd file missing is the AD7771 which I am testing still (more like it's sitting in my window sill while I am distracted by summer). The others all work though with drivers I have written to test them. This repo will get reordered and consolidated but I'm transitioning with the better hardware and all kinds of ideas to improve this as an open platform for low cost but effective biosensing tech. The random stuff is mostly BOMs and some exports I forgot to add to the git .ignore file, but anyway I haven't had anyone dig into them yet. The software with this will be generalized for both EEG/EKG, HRV, and FNIRS.

The HEGduino shits the bed depending on power source and sometimes due to the WiFi power draw on the ESP32 even at a low power setting, but it is okay depending on the laptop. Obvious solutions are battery power and moving the ADC away from the microcontroller to lessen power fluctuations, as well as consolidating the whole thing to one flex board so the connecting wire isn't causing issues but I made those choices deliberately for making it more of a tinkering kit.

dumblob commented 4 years ago

Ok, thanks for shedding more light on the process.

Hey there, I think the only brd file missing is the AD7771 which I am testing still (more like it's sitting in my window sill while I am distracted by summer).

Why do you focus on AD7771 based variant if you already have ADS1115 working?

Btw. in the crowdfunding campaign it seems you're shipping HEGduinoV1. Why did you develop also the other designs (MAX30112HEG and MAX86141HEG)? What are the main differences?

dumblob commented 4 years ago

Any insights? I've shared HEGduinoV1 schematics with one professional and if it catches his interest, he might help you out e.g. with the TODO items.

joshbrew commented 4 years ago

@dumblob

Hey didn't see your last reply. The ADS1115 is just a 16 bit ADC and does not meet my current needs. The MAX chips are 19 bit and tailored for pulse oximetry, the MAX86141 version is the basis for my upgraded hardware (listed on my website @ hegalpha.com) while the MAX30112 was another attempt. The AD7771 is a 24 bit 8 channel simultaneous sampling ADC which is the base of the FreeEEG32 project I'm helping launch as well as for an 8 channel breakout board I am trying to get working on my own still. That 8 channel board will become a mixed EEG/FNIRS device that is cheap and totally open source, and also really good as a piece of hardware. This all is part of a wider project for low cost open source biofeedback hardware and trying to make an ecosystem of sorts around all of it.

Why? Because this beats the hell out of doing anything else and has been a better learning experience than my college education. We gotta take up the good fights we can fight, you know? This is for people in my life who need it and otherwise don't have access.

HiLivin commented 4 years ago

In what program were those files made? KiCad doesn't seem to support the format...

joshbrew commented 4 years ago

@HiLivin hey they're just EAGLE files, they can be imported into KiCAD pretty easily

HiLivin commented 4 years ago

Yup, my bad.