In my kitchen I have two small little shelves, under my Beer Tender, with four beer glasses per shelf. What I would like to do is, a LED under every glass. That makes a total of 4 LED's per shelf.
What I want to make: if you remove a beer glass from the shelf, the LED needs to turn off. If you place a beer glass on the LED, the LED will turn on.
I know how to control multiple LED's with my Arduino, but I can I accomplish the 'beer glass detection'? Maybe IR sensors?