My Daughter loves the Octonauts. So after seeing how much she enjoyed the Octoalert tablet app i wrote for her, i decided that i would make her a hardware version.

Basically what this does is plays a random sound from the SD card when the button is pressed.

i grabbed some sound bites from the show using Audacity's loop back adaptor: http://sourceforge.net/projects/audacity/

and loaded those on an SD card.

Then just for fun i added an ESP8266 so it could be triggered via a tablet app.

the end result was a small box with a big button that she can push.

It was a big hit!

Step 1: Electronics

Bill of Materials:

Adafruit Wave Sheild $22.00 + SD card

Sparkfun Big Dome Button $9.95
or
Economy Dome $5.95 (i used this and wish i had gotten the better one)

Arduino Uno$24.95

Switch WARNING! i used a generic one from an old toy so the hole in the box will be different sized.

4xAA holder $2

3w amp module $2 - PAM8403 2X3W Mini Audio Class D amplifier board 2.5-5V input

Speakers or old over ear headphones something like this would work: LINK

Some wire

Most of the parts i had in stock so it was sort of work with what i had, i only had to buy the adafruit wave sheild.

Total: 63usd.

Tools:

Laser cutter (for the box, you can use any enclosure.)

Drill (if not using the laser)

Heat glue (to glue parts to the box, could use velcro)

Soldering Iron

Step 2: The Code

The code is simple.

it uses the WaveHC library from here: https://code.google.com/p/wavehc/

you name the files 1.wav - 5.wav then the arduino generates a random number and will play that file and light the button LED.

its very low tech.

octoalart.ino
Download

Step 3: Grabbing Sound Bites

So i can't share my sound bites, however i can show you how to do it. basically i used audacity to record sound bytes off my laptop that were playing on youtube.

Step 4: Make a Box

The finishing part of this is the box. its the part that everyone's sees so you need a good box for it.

I have attached a black copy of my box.

Step 1: Measure your parts and work out how bit. Then go here http://boxmaker.connectionlab.org/ and put in your sizes 8inx6inx3in.

i made mine a bit bigger so it would have a good feel.

Step 2: Add cut outs for the speakers and buttons. Remember kids, measure twice cut once.

Step 3: Decorate, now i haven't included my decorations, but you can add your own. i used the trace bitmap feature in inkscape on octonaut colouring pages:LINK

Step 4: Cut it out :) i used a 3mm or 1/8inch birch ply. it took about an hour.

Step 5: Once its cut out, glue the edges with wood glue and clamp for at least 30mins (or the time suggested on your wood glue).

Step 6: insert and glue in the electronics. i used velcro on the arduino as i will want to remove it later and the rest was heat glued in.

Just put batteries in it and you are done!

I hope you have enjoyed this! please share any that you make, i'd love to see them.