first of all, I am completely new to Arduino and this forum, so please forgive me for all my stupid questions and assumptions and probably wrong terminology =)
I would like to measure diverse body signals during meditation such as heart rate (ECG), muscle activity (EMG) and if possible also brain activity (EEG), skin conductance, respiration and eye movements at the same time. It is important that I would like to place about 10-15 EMGs at the trunk at the same time, not just one.
From what I understood, this is generally possible with Arduino and there are a lot of specific boards from different brands for some of those body signals. First of all, is there sensor boards with good quality and reasonable prices you recommend?
It also seems that some boards such as the Mikroe click boards can be simply attached to the Arduino uno and work pretty much plug and play. However, it looks like I can attach only two or three clicks to one Arduino - is that correct? Is it the same with other boards from other brands? Is there a workaround to sort of stack the sensor boards on the Arduino or would I have to use about 5 Arduinos in parallel (if that works)? Or is Arduino not the right solution then?
Welcome to the Arduino forum, Renee.
That is a very big project for a beginner. There is nothing about the Arduino that is 'plug and play". That is why it is a hobby and learning experience.
What is your programming experience?
Suggest you begin at the beginning and get one Arduino board, one power supply and one device of your choice and begin to experiment and learn.
Most Arduinos have very limited memory, so storing "lots of" signals, or capturing even one signal for a significant length of time, is always a problem. Most people use an SD card, or send the data to another computer.
Since you are interested in body electrical signals, I suggest to learn more about how that works with a starter set, maybe something like this EEG kit (currently backordered) or Myoware.
Thanks to both of you. Yes, starting out with one or two is also what I was planning. But I want to be sure this setup is sufficiently scalable in advance so that I won't have to change to a completely different solution when reaching X sensors. What do you think - would that work?
My programming experience is moderate, I guess. I programmed mostly in Java and learned the very basics of C, C++, Python etc. when I was a student. I am aware that it's not only plug and play and that coding is needed but there is a lot of tutorials out there, also for bio signals. I am sure I will need some time to remember and learn but that's part of what makes this project interesting to me.
I also considered the Mikroe and Myoware sensors, @jremington but I cannot judge their quality or potential issues I might run into with those. And I was planning on transferring the data to the computer right away - I thought this was the standard approach
The only way you will find out is to try them. They aren't expensive, and it will most likely be a worthwhile learning experience.
I was planning on transferring the data to the computer right away - I thought this was the standard approach
For some, limited to standard Arduinos like Uno, Nano or Mega. Faster MCUs with much larger amounts of memory are now available, can do all the processing and still be programmed with the Arduino IDE. Consider the Teensy series, or ESP32.
It is often a knee jerk reaction beginners have of just having one Arduino for each task it is almost never the answer.
Each type of sensor has its own challenges and also its own ways of making it work with other sensors.
In terms of your application then you will not need to acquire the data very quickly in computer terms. Have you thought what you want to do with this data when you have it? Will it form a sort of feedback loop where you observe the data yourself while meditating? If so that that act will introduce a sort of feed back condition which will itself distort the data you gather.
Eye movement with your eyes closed is tricky to monitor.
I don't need to do anything with the data right away like biofeedback or any analysis. I want to collect data from several meditations and then see if I can find anything unusual. So I don't really care when the data is moved to the computer and how - I would go for the easiest/ most suitable.
Hmmm.... looks like a perfect use case The thing is, we developed an Arduino-compatible wireless ECG sensor quite a while ago - name uECG - and just recently made a similar one for EMG - name uMyo. Both can connect directly to ESP32 via BLE (as well as other Arduinos via nRF24 module) and quite a few of them can work in parallel: uMyo library supports 12 devices now, possibly up to 16 would still work reasonably well - need to test that. All of those are open source, have libraries and you always can directly ask the guy who wrote all the firmware (that would be me)
