This will be my first serious Arduino project. Greatly appreciate your guidance on the question I have.
I would like to detect if someone is sitting on a chair. Preferably, I need a binary decision directly from the sensor. If not, I know the range of weight I need to detect and I can detect the analog weight (or equivalent) and can deduce the binary decision.
My question is what should I use as a weight sensor? I can think of three possibilities:
1. Use FlexiForce: http://www.tekscan.com/store/flexiforce-sensors.html
Way too costly even though it sounds like it does exactly what I need. Is there a low cost alternative?
2. Pressure sensors (such as, Sensore pressione MD-PS002)
Elsewhere in this forum, I read a lot of associated work needed to make it work. Is there a similarly priced (=cheap) item that simply give the binary 1 or 0 when it is sat upon?
3. Piezo sensors
I am not sure if this is a solution for the given problem. It might be too sensitive etc. But I am open to it if it works.
For my application it is important that the sensing surface be flat and not something like: http://www.omega.com/ppt/pptsc_lg.asp?ref=PXCPC&Nav=
Thanks very much in advance for your help.