Champaign-Urbana Community Fab Lab
Champaign-Urbana Community Fab Lab

Introduction to Arduino

This week’s lab was an introduction to the Arduino. I am fortunate to have a background in Arduino from both my classes and my hobbies, but I still picked up some new information in class. I had never worked with an ultrasonic sensor before, and it was surprisingly easy to use! Its sensitivity could have quite a few future project applications. 

One nuance of the Arduino that would be helpful for my peers without an Arduino background: when working with digital pins, the digital pin itself is providing power when the pin is high. There’s no need to have a circuit between 5V and ground; current will go from the digital pin to ground. 


For my Arduino-sensor concept, I decided on a tea-brewing robot that uses a temperature sensor and a servo to automatically start brewing a cup of tea when the temperature drops below a certain point! It’s not practical, but I thought it would be a fun way to incorporate both the sensor and some basic robot-like motion. 


Since I have had experience with Arduino, I decided to go ahead and implement this concept. Below is the loop code I drafted for this robot. If I were to redo this project, I would refactor the second if/for statements to be a while loop, but this code worked well for the first iteration. I had to play around with the max/min angle of the popsicle stick on the servo to get proper teabag motion. 

Below is a video of the final result! The body is a cardboard box with a hole cut out for the servo. A popsicle stick is rubber banded to the servo, and a teabag is draped over the popsicle stick arm. Finally, a cup of hot water is placed below the teabag, and the robot gently bobs the teabag up and down for a period of three minutes. Even though it’s a whimsical invention, I’m proud of the final result! I think it’s a cute application of sensors and servos, and a fully functional final result.