I found a similar topic here, but it wasn’t exactly what I needed.
I am using an Arduino Uno and I want to connect 1-1 metal electrode to each of the 6 analog inputs. The electrodes will measure the resistance in different liquids. The experiment would be conducted over a longer period. Every 30 minutes, the resistance in the liquids would be measured for 10 seconds, taking measurements once per each second. Thus, I will have 10 measurement points for each electrode. The electrodes would measure one after another, not simultaneously.
The serial monitor should display the measured data, the analog input number, and the measurement time (30 min, 60 min, etc.) in one line, separated by commas.
For example:
A0, 30 min, 11456 Ohm
Measure 10x
A1, 30 min, 15265 Ohm
Measure 10x
etc
No current should flow through the system in the half-hour intervals between measurements (would it be appropriate to implement this with a transistor?). If possible, I would not like to use an external power source other than USB.
It would be good to connect the configuration on a shield so that when in use, I don't have to connect the wires individually again, just attach the shield to the Arduino.
Could you help with this project? I would be grateful for a Tinkercad assembly diagram and the code as well.
Thanks in advance for your help!
If you want I can move your request to a section of the forum where you can discuss payment with any interested forum members. I am not sure what you plan to contribute to your own project, so I assume it will be money.
You are unlikely to find exactly what you want, and probably no one will do all that work for you for nothing.
Here we like to help.
Write (or find and modify) a sketch to read one electrode continuously and print that value to the serial monitor.
That will get you started… post that sketch here, along with a diagram of how you are developing the analog voltage to read from the electrode.
Your title suggests that the sensor operates by presenting a varying resistance, this would be read by using a voltage divider.
Post a link to the electrode you using.
a7
A vary curious project. I wonder at your ability to know the difference between galvanic reaction of the metal plates and the resistance of the liquid.
I am in academic research and try to avoid purchasing overpriced manufactured equipment, as I do not have commercial purposes. My goal is to construct a DIY TEER (Trans Endothelial Electrical Resistance) tool for my research project.
As a newcomer to the Arduino world, my contribution to this project has been reading through articles to understand the specific key points of the tool. I built a functioning single-channel electrode setup, but I am encountering difficulties with the multi-channel version.
The electrodes are simple metal rods coated with carbon ink.
Here is an image illustrating TEER: https://www.researchgate.net/figure/Schematic-of-Trans-Endothelial-Electrical-Resistance-TEER-measurement-system-with_fig7_330318446
I used this video as a guide for the single-channel TEER setup: https://www.youtube.com/watch?v=dlz24jtwKrQ .
The main difference is that I replaced the second resistor with the electrode wires.
TEER uses an AC current. Your simple ohmmeter uses DC. I imagine that will make a difference in the measured impedance.
The Arduino ohmsmeter in the link is simple.
Please post your multi-channel version sketch, and describe the difficulties you have encountered.
a7