Arduino Projects

Let's have some fun exploring how microcontrollers can be used to understand nature at a deeper level.

In the old days explorers would go out on sailing ships to discover strange new lands. Today we use PCs and microcontrollers to investigate nature's wonders!

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100: A Little History
In the old days (when I was young back in the 70's and 80's) we had "microprocessors." They were great but needed a lot of external hardware in the form of Random Access Memory (RAM), non-volatile memory (EEPROM) to hold the program (that we erased by putting it under a UV light), Analog to Digital Converters (ADC), and a bunch of other external components just to do anything. Today we have Microcontroller Units (MCUs) with all that stuff on board. That simplifies things a lot! Also, we used to program by hand on coding sheets using hex characters. We used pencil and paper (and a big eraser) to write down address numbers and instructions. A little later we got to write in assembly language on a PC and had a compiler that would convert it to machine language. Now, that was a big step forward, but it was still a pretty low level process!

I'm glad for the experience because it gave me the chance to see how things work at the component and machine language level, but the tools we have today are so much more efficient! Not only do they simplify many of the hardware complexities, we get to use software libraries that hundreds of very bright people have written! When you get to use other people's hard work for free - that's a good thing!

For these projects we are going to be using the Arduino UNO as a data logger to help us search for the underlying forces at work in the natural world. We will analyze natural events and look for attractors. If we discover some underlying forces at work how exciting is that!

The field work will involve recording phenomena as diverse as wind, rain, waterfalls,  and light reflecting off a lake. You get the idea!
200: Arduino Projects
Dripping Faucet with Triggered Interrupts (video)
Arduino Sketch (ino)
BASIC Display Routine (bas)
Schmitt Trigger Schematic (jpg)
Schmitt Trigger Trip Points Diagram (jpg)
Schmitt Trigger Input/Output Diagram (jpg)
Dripping Faucet Audio Recording (mp3)
Dripping Faucet Datalog (txt)


This is an amazing plot of time intervals for a "random" dripping faucet! What seemed pretty random turned out to have an amazingly complex structure! Looking at the plot, I think I can see what's happening.

Blowing in the Wind (video)
Arduino Sketch (ino)
BASIC Display Routine (bas)
Schematic (jpg)


The wind was blowing the tree branches around like crazy and they were casting shadows on my back porch railing. The movement looked pretty complex and chaotic. So I captured it with the Arduino. When I displayed the data set on the computer a distinct pattern emerged!

Arduino: Data Logging in the Field (video)

You can use the Arduino as a data logger in the field because:

1. The Sketch is stored in nonvolatile memory.
2. The program will start automatically once it is powered up.
3. It can be powered from a 9V battery.

Simple and Inexpensive Motion Sensor (video)
Arduino Sketch (ino)
BASIC Routine
Data Log (txt)


Here is an idea for a simple motion sensor made from a yardstick and a potentiometer.

The Dripping Faucet Project (video)
Arduino Sketch (ino)
BASIC Routine (bas)
Drip Recording (mp3)


The dripping faucet sounded pretty irregular, but the plot is amazing!

The Dripping Faucet #2 (video)
Arduino Sketch (ino)
BASIC Routine (bas)
Drip Recording (mp3)
Datalog (txt)


Here is another dripping faucet that also had a random sound, but the plot is very different from the first one. Can you explain it?

Capturing Analog Data (video)
Schematic (jpg)
Arduino Sketch (ino)


I use a variety of sensors to capture natural events including light, sound and motion.

Pushbutton Interrupts (video)
Schematic (jpg)

Arduino Sketch (ino)

This is a simple project that uses both interrupts to change the period of a blinking LED.
300: Off Beat Articles, Funny Stories and a Bit of Computer History
Love, Passion, and Bat Switches (pdf document)

When I was young I dated a beautiful young girl. She was bright and funny and she eventually became my wife. Maybe she didn't have the same passion as I did for technology, but she went along with the program. In fact she worked for several years as a technician for Digital Equipment Corporation (DEC) before transitioning to the health care profession where she really thrived! Anyhow, this is a story about our first dates. God bless you Patty for putting up with me!


"Enter" vs. "Return" (pdf document)

Computer keyboards used to have a "Return" key. Some had both "Return" and "Enter" on the same key. Today you will usually just see an "Enter" key.  There is a fundamental difference between the terms "Return" and "Enter." I hope this article brings back some fond memories for us old guys, and includes some interesting stuff for you youngsters out there!



Math Club Computer (pdf document)

Wickenburg High School Math Club Builds Computer (1975)


What great memories! It was way back in 1975 when our Math Club built a "working" digital computer on a 4x8 sheet of plywood using paper clips and flashlight bulbs.

A fun project and a great learning experience.