Hello forum i am new so please bear with me.
I am looking to detect whether an object has been placed on a flat "mat" of some 3x3 cm. I have looked into force sensors but thinking its overkill as i just want a binary anwser of if something has been placed on it. the item will weigh approx. 200 grams. Do you have any suggestions to what sensor i could use?
Thank you.
Simple plate hinged at one end with spring to hold it up, and simple lever switch that is closed when weight is placed on the plate:
You mean these force sensors ? Force Sensitive Resistor - Square - SEN-09376 - SparkFun Electronics
That is not overkill, but they have restrictions (amount of force, accuracy, temperature, can't deal with pressure pinpoints).
A mat that detects if something is on it ? Well, yes, some make a DIY switch, either with conductive thread or conductive fabric, sometimes in combination with a capacitive detection instead of just a contact.
Here are some ideas:
How long will those DIY switches last ? I don't know, but I doubt it will be reliable.
A plate and a switch as CrossRoads mentioned is simple and will work.