Product

The Compost Monitor encourages environmental awareness by publishing tweets that document the progress and activity of the community's compost bin. The bin itself is represented by a cardboard box with a flip-top lid. A pushbutton on the edge of the bin can detect when the bin is opened and closed. An ultrasonic sensor on the inside of the lid detects the height of compost within the bin. The Particle is concealed within the bin. 

When the lid is closed, the ultrasonic sensor will measure how much compost is in the bin by measuring the distance between the lid and the top of the compost content. If compost has been added, it will publish a tweet saying how much is currently in the bin. These tweets, which represent positive action in the community, contribute to the community's points system. 

The product's circuitry and code is included below.