The Waiter Coaster

A coaster with LED light indictors that notifies waiters when you need service.

IMG_0179 IMG_0177

I used an FRS censor to create three thresholds that identify when a class in full, half drank or empty. Within the arduino code I used several “if else” statements that distinguish between the weight of the glass.

IMG_0174 IMG_0182Then I used a glue gun to and wooden sticks to connect the two parts.


The FRS censors are calibrated to recognize three thresholds or weights.  When the glass is full a red LED indicator turns red. When the glass is half full the LED indicator turns tell. This tells a waiter that you are ok and don’t need help.  The final LED state turns green when the glass is near empty, indicating that you need a refill.

Author: George Crichlow

About Me: I am a Strategist interested in the relationships between people, culture and technology. My ambition is to create products and services that have commercial and cultural impact.