Can somebody suggest some sensor which can be mounted on a seat to measure the weight of a person sitting on it ??

 

Just the presence of the person or their actual weight?

 

Currently, i'm interested mainly in detecting the presence. The seat can accelerate up or down, whose actual value is yet not known to me. If actual weight can be measured, it might be more useful.

 

Has anybody used FSR (force sensitive resistor)?
http://www.sparkfun.com/products/9376

 

Butt temperature sensor?

 

Didn't automakers use some sort of human body presence sensor in the seat of the car to interlock with the seatbelt and/or car starting procedure? This was maybe 25-30 years ago.

 

I think auto manufacturers still use a seat sensor to arm the passenger side air bag.. No person= don't deploy the air bag in a collision.

 

A quick trip to the local Pick-n-Pull may result in a cheap solution.