After attending a Summer Camp at MIT I was introduced to the Arduino. The Arduino is a microcontroller that uses an open source platform which allows for fast prototyping of electrical engineering projects. I found the Arduino highly interesting, and I decided to purchase an Arduino Uno. Below I will describe one of the projects that I built using my Arduino.

The Arduino I bought came with a breadboard, motor, sensors, and basic electrical components. To the right, you can see the Arduino Uno and several components (resistors, wires, phototransistors, and an RGB LED) on the breadboard that allow the color mixing project to work properly.

In this project, I used phototransistors to identify how much red/green/blue light is in the surrounding environment. Based on the light detected, the Arduino was prompted to emit different light levels and colors through an RGB LED. To accomplish this, I connected three phototransistors to the breadboard and covered them with different gel covers that allow certain wavelengths to pass through to detect different colors. The Arduino then processed this as voltage input which correspondingly changed the color and brightness of the RGB LED.

Below, you can see what happened to the RGB LED when I covered different photoresistors. In the left picture, I covered the red and green photoresistor. This meant that the only light that could be detected by the Arduino was blue light, and this prompted the LED to emit blue light. In the right picture, I covered the green photoresistor and partially covered the blue photoresistor. This meant that red light and some blue light was detected by the Arduino, which prompted the LED to emit a purple light. The Arduino was also able to detect different amounts of light (dim/bright) and adjusted the LED’s brightness using pulse width modulation (PWI).

To code the program for the Arduino I used the Arduino IDE. The Arduino IDE uses C++ along with several special methods and functions. To the right you can see a screenshot of the code I wrote to allow the Arduino to detect, compute, and emit voltage.

By being able to experiment with my Arduino, I have learned more about circuits. This has spurred my interest in electrical engineering, and I would definitely continue to use this amazing tool and recommend this for anyone interested in electrical circuits.