Week 2: Enhancement to your homemade switch

Project Name: Don't stop drinking (a.k.a "Don't touch me" box)

I do not play with salty water this week, since liquid as a conductor is not very stable. However, I still want to continue the subject of serving food.

The schematic
I want to make a parallel circuit and the switch connect either path to make a complete loop.

When a cup is put on the coaster, the red light is lit up.
Otherwise, the green light goes on continuously.

The vivid image of the circuit

The vivid image of the circuit

The actual schematic.

The actual schematic.

Then, here comes Arduino.

By using Arduino, I can code all these instructions, so that I do not need a green LED light and a red one for my purpose. There is a kind of LED light that the color of light can be changed and controlled by Arduino.

I played around with the assets and made the circuit work.


However, as the sensor is quite heavy, it can’t be mounted onto the ceiling of my box without keeping dropping down. I changed the sensor from a distance sensor to a photoresistor, which is super light weighted.


This works with other object, too.

So, I rename this project “Don’t touch me” box. Basically if an object is put on the box, the red alarm light will be light up..