Solitude is my muse, and taking things apart keeps me from getting depressed. However, it is still nice to hear other people say nice things so I decided to convert a toaster into an interactive art project that says nice things when something (usually me) walks in front of it.

The Build

TAKE IT APART!

The first step to any great project seems to begin with a bit of destruction. Good. Nothing really clears my mind like taking something apart. Yea, I laughed when I bought the toaster and I'm still laughing now.

The toaster was soon gutted and a bunch of innards where chucked in the waste bin.

Make some mounting thingies

For this build, I planned on using the Raspberry Pi from the NaNoBox and since someone is a hobby hardware hacker hater, there are no mounting holes on my Raspberry Pi. sigh. Who's a liar? ME (sort of). I said I wouldn't use the Raspberry Pi for a similar project. Fortunately, this project isn't too similar.

A small wooden block was epoxied to the toast box (at least that is my name for it). Similarly, a piece of thick plastic from VHS case was also epoxied to the toast box.

Circuit from the shell

Surrounding the toast box is the toaster shell, and this is the circuit board that was mounted inside of the toaster shell. On the circuit are 3 buttons and two LEDs.

After a bit of scratching at the circuit board and some soldering, the buttons and LEDs where ready to be wired up.

The circuit back in the shell

Oh man, look at that rat's nest of wires.

This is the inside of the shell with most of the wiring finished. This includes the PIR thingy. What's a PIR thingy you might ask? good question.

PIR Thingy

Hey look, kids, it's a PIR thingy! This Passive InfraRed sensor thingy was purchased at https://www.adafruit.com/products/189 for 10 bucks.

A notch was cut in the toaster's lever channel and the PIR was hot glued into place. Damn, I love adhesives.

Sound!

My buddy gave me a small USB amplifier and speaker combo used for plugging into a mobile phone.

In my haste, I obliterated the amplifier before taking a pictures. What a shame. The wires on the amp were to frail for my needs so I soldered on some heavier wires for audio in, audio out, and the power connector. Since the amp was originally powered over USB I figured I could wire it to the 5v pin on the Raspberry Pi. The speaker is from another portable amplifier.

Buckle up

Like I've said may times, the designer of the Raspberry Pi hates me and didn't include mounting holes on the board. Because of this, I needed to find a creative way to keep the board in place and my solution was a nice little 'belt'.

To keep the number of cable going to the toaster to a minimum, an old USB 802.11g was connected to the board.

Add some more LEDs

Aside from the two bright blue LEDs on the toaster shell, I added a green LED to each slot of the toaster box.

All Together

With much finagling, the toaster box and the copious amount of wires was stuffed into the toaster shell and the end result was put on a desk and pointed at the busiest foot traffic area of my home.

The toaster lever, although no longer in use, was hot glued back where it belongs and helps hide the PIR sensor.

What does it do?

When the sensor detects movement, an audio file is selected at random from a directory of audio files, and played through the speaker. While the audio is playing, the LEDs are flashing.

some of the setup

The code for running the toaster is written in python and utilizes gstreamer-0.10 for audio playing. In order to get gstreamer to default to playing through the 'audio out' on the Raspberry Pi, I had to edit the /etc/asound.conf file to look like the following:

pcm.mmap0 {  
  type mmap_emul;  
  slave {  
    pcm "hw:0,0";   
  }  
}   
  
pcm.!default {  
  type plug;  
  slave {  
    pcm mmap0;  
  }  
}  

Switches

Due to the lack of GPIO documentation for the Raspberry Pi, most tutorials for the device involved wiring in "pull-up" resistor which means that extra work is involved just to get a simple button press to register. However, pins 3,5,7,24, and 26 have built in pull up resistors which makes these pins ideal for connection switches.

Most (if not all) of the information I needed for programming the pins on the Raspberry Pi came from http://www.panu.it/raspberry/ and not from the Raspberry Pi website. Seriously, this is wrong. The RPi website should have some useful information, but alas, it does not.

What's next?

The power for the amplifier was specifically not taken from the one remaining USB port. It would be fairly trivial to plug a USB camera into the USB and, when the PIR detects motion, have the camera take a picture and then upload the picture to a back up server. Hella cheap home security system. booyah!

Also, I need to figure out what to do the the buttons.

if your browser doesn't play ogg files, you should switch browsers

Why? Because if your browser doesn't play ogg:

1. your browser hates freedom
2. you won't be able to hear
   duh!

The System

Like almost all of my computers, the toaster is running Arch Linux

Now quit reading and go make something...