Tuesday, August 27, 2013

Wind Chimes (Arduino, Raspi, and Magnets!!)

Arduino Uno Talking to Raspi via Serial
I'm going to do a quick post on another project I'm working on.  This is not complete yet, but I'll share my progress to date.

Here's the concept:
I'm building a wind chime that does not actually chime, well, acoustically that is.  Instead, it will allow me to play any sound for a chime instead of a metal or wood clunking sound.  I will capture the "striking" of a "chime" (yes lots of quotes) using analog sensors on the Arduino, and then communicate a command to the Pi via a serial line. I am using the Arduino for it's analog pins and its ability to sample incredibly fast.  I'm using the Pi to play sounds simultaneously (Nope, there is no simultaneous audio shield for the Arduino).  Pi audio is a longer subject worth of its own post. But the audio you hear in the video below will not be the finished product.

Saturday, August 17, 2013


Next Project!

We brainstormed a lot about what to do next.  There was even a brief deep dive into possibly building a self contained tomato growing cabinet for my basement, but alas the investments in this project just outweighed a hobby budget.  After a long hot weekend over the 4th of July, we finally landed on a beer cozy that keeps your beer cold.  A Franken-Stein!

These posts will be a little different than the post project Frankenfeeder as I will try to keep up with this as we go.  So far our concept is this:

  • Use a peltier plate (a solid state component that moves heat from one side to the other when passing current) to cool the beer can in a beer cozy.
  • Use a heavy duty 12/18V battery from an old drill set to provide the heavier amperage and voltages needed to run a peltier plate
  • Drink very cold beer on hot days

Frankenfeeder Part III

Pi stuff and Reassembly

This is Part III, Part II is here.

The Pi and what you can do with it is a deeeeep subject.  I'll just stick to the highlights.  Turning on/off GPIO pins, high level Wifi and sundry, and the script.

GPIO Control

Wiring Pi by Gordon @drogon, is an excellent project for low level Pi IO control.  Actually his whole site is just pure awesomeness if you have the time to read.  Anyway, I followed the instructions on downloading and installing Wiring Pi on my Pi.  I've heard rumors this is included in the base distro now, but you might want to check your version of the distro to be sure.
With the wiring pi package there is a binary, the gpio util, that allows you to issue command line commands to see the state of the pins and turn them high/low.

Frankenfeeder Part II

Pi Controlled

This is Part II of the frankenfeeder project.  Part I is here.

Energized Relay (ON)So how to close a circuit with a Pi.  Simple, use a relay.  A relay's job is to close (or open) a circuit when current is applied to it.  (a nice illustration is here where I borrowed the image) So just pop a relay onto a PI GPIO pin and off we go right?  Nope.

Frankenfeeder - Part I

Kick off:

A while back my folks moved to town in their retirement to be close to their mess of kids and grandkids.  It's been great having them closer and in our daily life.  My dad and I decided to spend a little time each week just geeking out with something completely unrelated to our jobs (he failed to retire properly) to rest our minds from the daily patterns.  He is a pseudo-retired pastor and I do Cloud Computing.  But we both enjoyed and wanted to learn more about hobby electronics or just making stuff.

For our first project we decided to create something that would allowed my dad to feed his dogs remotely if he and my mom were out gallivanting (technical term) about.  Don't worry, the dog door allows for the post-processing to occur safely.

We did some research and found this cool project by Amanda Ghassaei:


Why this blog?
This is my third attempt at starting a Blog, so why now? why here? Well several reasons.
  • I have been doing a lot of electronics experimentation and I am inspired to share some of my stories. I thought about doing instructables or something, but couldn't bring myself to get to that level of detail.  So I'll try to share stories here.  If there is interest I can share more.
  • I enjoy writing.  Possible future posts and news about pending novel publishing, short stories, etc.
  • I wanted a place to share ideas, and thoughts, I guess thats a blog
Ok, that's about it.  So the content here won't be frequent, but hopefully it will be worthwhile.

Oh, and the name . . .. While the name might seem self evident after a few posts  but while I was considering what to call this, my son started relating a dream he had and was very excited that it was full of "Lots of cool geeky things," his words.  I thought, Perfect!  And here we are.  "Lots of cool geeky things."