In my project, I am developing a capacitive sensor based system which attempts to identify if two real world objects(*) get in contact with each other. I have done my homework (some) on Capacitive sensing and I am able to detect simple touch events either via classic charge/discharging-timer or oscillator 555 IC approaches. However, I still don't know exactly which object is in contact with which, and in my project, it is important that I determine this information.
So, the question I have is directly related to capacitance but in a somewhat general framework:
What can be said about two objects touching when it comes to their capacitance?
- Are two objects put in contact sharing the same level of capacitance?
- At the very least locally speaking, would it be such that if measured by sensors located on either side (the touching object, and the object being touched), we would read similar capacitance or at the very least relatable figures?
- If not the actual level of Cap, would the "capacitance profiles" (dC/dt) be similar or relatable?
I would be interested to hear what people know (or think) on this subject and would appreciate any reference or link on existing research taking me in the "right" direction. Thank you.
*: real world objects would be (for example, but not limited to) a metal rod, and a sheet of conductive foil. For this conversation, I aim to remain realistic and so we are NOT talking about a piece of wood and a cut of fabric, but focus on reasonably conductive elements made primarily of metal.