Guide

www.SquishyCircuits.com Page 4
Arduino
From the Arduino website, “Arduino is an open-source electronics platform based on easy-to-use
hardware and software. Arduino boards are able to read inputs - light on a sensor, a finger on a button,
or a Twitter message - and turn it into an output - activating a motor, turning on an LED, publishing
something online. You can tell your board what to do by sending a set of instructions to the
microcontroller on the board.”
Image credit: Arduino
We have chosen to write this guide for Arduino boards because they are popular, inexpensive, easy to
use, and have many educator resources. If you are completely unfamiliar, we suggest viewing the
Arduino website, www.arduino.cc, which has guides/tutorials and the software required to program
your Arduino board.
Arduino boards contain a microprocessor (essentially a small computer) and a host of useful prototyping
tools. Using the Arduino software, instructions, called code, are written and programmed to the Arduino
board.
Voltage Dividers
Arduinos have analog inputs which measure voltage. If we were to provide 5 volts on one side of the
dough and connect the other side to ground, there would always be 5 volts going through the dough.
This really does not do anything useful.
But, if we put another resistor in the same circuit, now we can measure the voltage at the point in-
between the resistor and the dough. As the dough’s resistance changes, more or less of the voltage will
be present at that point because the 5 volts is split proportionately between the two resistances. This is
called a voltage divider and is a fundamental circuit for engineers.