Make a bluetooth-activated talking dog collar for Halloween or just to show off at the park! This intermediate electronics project was inspired by Dug from the movie Up-- his talking collar translates his thoughts for communicating with humans. Using the Audio FX board and Bluefruit Micro, this project enables you to trigger sound samples through the Bluefruit LE Connect app for iOS and Android. The sounds are played through a mono amp connected to a mini metal speaker.
The collar itself is made from a leather belt, with 3D printed "greebles" to make it look like the collar from the movie.
It's easy to adapt this circuit for any phone-triggered audio project by swapping out the sound samples!
Before you begin, familiarize yourself with the following prerequisite guides:
For this project you will need:
video for gifs by Mike Farino.
The Bluefruit Micro has been discontinued, you can try using the Feather 32u4 Bluefruit!
This is a schematic diagram to clearly show the connections between components with minimal wire crossings — it does not represent the actual placement around the collar.
Download sample audio files and Arduino sketch are here:
One of the sequins is always on, sliced from the battery pack. The other is connected to an analog out on the Bluefruit Micro, so we can trigger it to light up when the sound is triggered to create a "talking" light.
We strongly recommend prototyping this project on a solderless breadboard first, if you can spare the second set of parts (the collar is assembled without header pins). When assembling things into the collar, things can get a bit confusing, so it's always nice to have a working version of the circuit to reference!
To make this movie prop replica, we designed some 3D files for the harder-to--find bits. Download the 3D greebles:
And assemble as shown (the stitching is purely ornamental). The selector knob is glued in place and does not turn or activate any part of the circuit.
Start by desoldering the wires on the speaker, then solder on longer, more flexible wires facing "in" instead of "out," so it will fit inside the dome.
Solder long wires onto one of your LED sequins (different colors for positive and negative is helpful), and thread the wires through another hole adjacent to the speaker dome.
The Bluefruit Micro and Audio FX boards share power via the connectors on the backs of the board (usually used for attaching a JST port). First tin the pads and the wire ends, then use tweezers to hold the tinned wire in place while you reheat the solder to make a solid connection.
Assemble the rest of the circuit according to the diagram, soldering small bits of wire to connect the boards' pins. Try to use short wires, but don't make them too short or that you can't see between the boards to double check your connections or troubleshoot.
Once your circuit sandwich is complete, you can wire up the components that are elsewhere on the collar.
Thread the speaker and sequin wires into the main circuit compartment, and strip, tin, and solder the wires in place according to the circuit diagram.
To attach the map light sequin, cut off the JST connector from your battery pack (it should be off and/or empty), then solder two wires onto each the positive side and the negative side. One set of those wires goes to the sequin, and the other set will travel through the collar to the main circuit compartment.
Phew, almost there! You haven't glued anything yet, have you? Ok good. Clean up your workstation and double check there aren't any bits of wire or metal hanging out in your circuit compartment, and position the boards so they're not touching each other.
Test the circuit and be sure it is working before proceeding to the more permanent steps below!
Only after checking that the circuit is complete and in working order, you can stick the layers of the circuit sandwich together with foam tape and close up the pouch.
It's also time to glue down the "talking" sequin and its dome, as well as the speaker dome.
E6000, shoe goo, and other permanent adhsesives are suitable for this project, but hot glue is not durable enough and so not recommended! Use a toothpick for precision application and wipe up any excess with a damp cloth.
To secure the wires on the inside of the collar, you can glue a piece of fabric to cover them, or stitch them down with a needle and thread-- your method will vary depending on the material of your collar.
Go get that doggie costume contest trophy!
The collar is not water-resistant, so power it down and remove the batteries if you get stuck in the rain, and bring an analog backup collar just in case.