Track-and-explode Wolf Collar...

Don't worry! First, this is a rebuild out of a movie so it won't explode for real and it won't be worn by a real wolf.
However there is fursuiting for which I am a big fan of and my own character (fursona) is a wolf and lives in a world of technology and total military control. This collar will give the image if you would step out of line, you will be severely punished.
(a future nobody wants to be part of, yet it is happing in the "world" of my fursona) 

So much for my own background story and motivation....
This idea excally came out of the movie "the running man" when in the beginning the collars are being shown in action, preventing prisoners from escape and later on being a problem when they needed to disable the "sonic deadline" before they could run away. However I wanted mine to be a lot nicer and have some real functionality and more in the animal spirit (and again!, no real explosives are used, I like my head for some reason…)

Video below:

Alright, some basic things about the design:

1. needs to pretty (of course)
2. practical
3  save (apart from the fact that it should explode)

Before I started this project I actually wanted to buy one of those "sportdog Tek 1.0" collars, they have very nice design features but we're to expensive. (still I really love to have one)  After some idea's, sketches and thinking about all the technical things as far as I could, I worked out the end result in a Cad program called "Cambam" a very easy to to use Cad program for Cnc machines. (they have a nice website you can check out)  The basics measurements came from the strap and quick release I bought earlier on a random website which I compared first to collars in pet shops.

Aluminium came from no other then broken Apple computer display's and bottomcases from the aluminium models. (current models) I can easily get these since some of them are being thrown away after replacement here in the workshop. Talk about recycle...

This is one step not anyone can do without a cnc machine...
Although you can do this step with a figure-saw, the results are never gonna be that precise as with a real cnc machine.
I used a Proxxon MF70 modified into a mini cnc machine to cut out all the parts.
(the MF 70 cnc kit works really well with Cambam and Mach3 software for those interested in cnc)

And shapes can be created in a lot of materials, the plastic pieces for the battery case and middle piece we're also cut with this machine. Learning this stuff is not really that difficult, I did not know a thing about cnc and this is just only my 3rd project on it.
Thank you youtube and everyone for the Cnc lessons on there it caan really help people!)

After the thicker and thinner aluminium parts were cut, I bend them into shape with a pvc tube and my own hands.
Carefully, with some protection against scrates and such...

You can see the basic idea coming together in one of the photo's.

After cutting the plastic pieces with the cnc machine, I needed to bend them in the right shape so it will fit nicer on your neck.
(I forgot to tell you that this will go on a fursuit not a real human neck so that is why the size is so much bigger, but I will wear it on my own neck to)
Plexiglass react's really well to heat by not melting but becoming more flexible, and can be easily be bend in the right shape.
And when you let it cool down again it will keep that shape without any problem.

I used a bit of metal to keep the heat from my heat-gun away from my desk, and oven gloves to hold the hot plexiglass while it was cooling down. Heat up the piece slowly and bend it the way you want it. Don't "force" the heat on it or you will burn the plastic.
It may take a couple of times and sometimes you only need to heat a part of it to get it right...  

Its finding out while fabricating on this one.  (Oh, and keep other stuff well away from the heat gun)

A difficult part that needed a lot of attention:
This battery case has a antenna on his side and keeps 2 times 2 battery cells (each 3volts 230 ma) a total of 6 volt's 930ma. (should be 10 hours of fun)

First sticking all the parts together with tape to keep them together, then drill a small hole all the way through all the layers for the screws to keep it together.
I used a little proxxon hand tool for this job on slow rpm to prevent heat, after that the threads in the base plate could be made.

By heating up the plastic in the previous step the holes for the battery cells, "warped" a bit. Now the battery's wont fit anymore and needed to be sanded down a bit to make them fit again. The cover will be the ground or negative when put together. The positive side will be explained in the next photo.

The metal strip you see here was heated to the point I could press it straight trough the plastic to the other side. I needed to heat up the metal and plastic multiple times before I could do this. The wires come trough holes that I drilled in there, one hole exactly runs like a L shape going down to the base plate making contact there. (ground) The benefit of seeing trough material is that you can see how you need to adjust your drill while drilling to get the L shape right.

Alright, some big things needed to be done here:

1. With a special drill (on top of the photo) I made space to lower the screw-head into the aluminum front.
2. Holes needed to be made (I used a proxxon multi-tool) and wirethreads needed to be made to keep it all in place later on.
3. The gaps didn't line up right since everything was bend later on, so I filed them down until they all lined up as they should.
    (just do this slow and keep checking your work)

4. I used a sanding machine to sand everything flat and made it look like one piece.
5. Slowly drilled holes in the side and glued the led's in the holes.
    I also sanded down the surface to let it reflect more of the yellow / red light. 

6. Already cut the wires to the correct length and soldered them, I used lots of glue to cover up the contacts, later on the wires will
    be painted black.

The quick release was sawed on with a sawing-machine and some black wire. (unfortunately I do not have photo's of that) 

After all the aluminum parts were cut out, I started to saw them on the black strap with needle and wire.
The tiny holes only allowed for 10 rounds of wire before the needle couldn't be pushed trough anymore.
Keeping everything together the first few rounds is the most difficult part of this and I needed to redo some parts again in the end.  (otherwise it wouldn't line up correctly)

The last photo shows the wires behind the battery case, I made some room in the back of the battery case to make room for the wires so the hole part would close without gaps.

In this collar goes a lot of circuitry, none of the wires should be overlapping each-other or worse: short out.
Here is how I did it:

The black wires you see here come from the sensor on the quick release, it will single the Arduino whenever you take the collar on or off. They are being kept in place by sewing them to the black strap and some glue to keep it from unraveling.

The coloured flat-wires go into the little holes I made in the strap to the other side.
They to were sewed on the strap on the other side to keep them from shifting around.

Yep, its a mess, but most wires will be connected later on and insulated with heat shrink rubber tubes.

The antenna will give the illusion that the thing can be controlled from far away and it is a nice feature to this collar.
(or the subject can be tracked down by the build in gps, oh dear…)
This black tube with some kinda extension on the end came from a little toy, it snapped of so I saved for when it became useful again.

The black tube was made from soft plastic so putting a screw into it to make some wire threads for later on was easy. In the battery cover I did the same and left the screw in there, I cut of the head off leaving the rest stuck in the battery case. With little effort you can "screw on" the black tube on like a nut on a bold. 

Then I used a heat gun to make the antenna soft and bend it in the right shape, needed to do that multiple times.
(just don't head it up to fast or you will burn the plastic or the hole thing goes out of control)

I ordered the led's and Arduino from the internet on conrad.com, but any "electronics" website will sell these basic things. However the piezo speaker was a other story, I kinda forgot to order it and nothing seemed to be small and loud enough. Until I had my "eureka" moment sitting on the toilet watching the cheap two euro clock ticking time away. I opened it up removed the speaker and put it back together again. (not on the toilet of course) Now we have a small and loud enough speaker. 

I created a little sketch on the arduino to run all the lights and sound like the way I wanted them. You can go here wild here in programming every individual led but it is all a matter of taste I guess. 
The script is really not that difficult, more like basic stuff you find in the examples of the Arduino software. 
Just have a look in the file down below... 
Testing was done on a breadboard with the same Arduino now sitting on the collar.

Now comes the difficult part: Putting everything together on this side.
First of all I cut some of the circuit board off because it was to big to mount it on the collar with the pointy edges.
The only room for the Arduino nano was in the middle, it needed to be removable so I soldered some pin holders first.
(you can cut these to the correct amount of pins) 

Next was this very small switch that I recovered from a broken toy.
It was soldered on a 90 degree angle with help from some jumper pins, this will be the main on / off switch.
In between soldering parts I drilled and tapped the holes for the screws that will hold all this together on the base plate.

The little piezo speaker needed to go in the middle because there was no other room for it,
I didn't like it because I wanted the wires to sit there but I really didn't have much choice.
The wires got some extra heat shrink insulation to cover up the happy colours, the circuit requirers
only two resistors so we will keep some room and a simple pull relief for the wires.

Next I painted the control board black to let it blend in with the rest, looks way better now.
I test fitted the control board and then cut the wires to the right length and soldered them one by one on the board.
Thanks to the removable Arduino you can easily put the hole thing (with spacers) on the collar with screws.
Then cover the screws up with the Arduino on top of that. The green rubber ring will (under pressure)
fill up the space under the strange angle of the circuit board and the aluminium.

A small test with a power supply showed that it worked fine...
I haven't made any schematic for you, but if you know how to program a Arduino I also assume you know
how to connect a simple led (times 4) a switch and a piezo speaker to it.
I know this side kinda looks bigger and it looks not the same then the left side, but I kinda like it anyway...

Script is here to for download now.  :D

The quick release on this is collar was bought from a random website here in the netherlands.
The little magnets came with a large order of neodymium magnets but you can buy similar magnets.
So..   How does the collar know when you have it on your neck and when you take it off?
Enter the world of the magnetic switch:

This black thingy here responses on a little magnet from a good 1,5cm distance.
This means if we put the sensor on one end and the magnet on the other we have a reliable switch system.
On the quick release was space for two magnets, some plastic was removed by sanding it down a bit to make more room.
The magnets we're glued into place to keep them there at al times.

Same goes for the sensor, although for some reason it only responded well if it was glued under a angle. Otherwise it would go on, off and on again and could confuse the Arduino. But that is why we test things like this first, with this type of glue you don't have second chances.

I needed to re-do some pieces to make sure it is all aligned right on the black strap.

I copied / paste a picture from a "explosion hazard" sign from the internet, and combined it with my own evil company logo.
(me is not a photoshop expert so I used paint instead)
Printed it all out and put it on normal packaging tape to protect the paper, then the picture goes on double sided tape.
We cut the picture out with a sharp little knife and apply it on the the collar. (home made stickers)
This will make it look like a extra "dangerous collar" kinda device.

Last picture shows the batteries this collar uses, one set of 6 goes for 3 euros.

And now its time to start wearing it, maybe later on a fursuit or yourself...
The batteries last about 8 hours in full uninterrupted use and the hole thing isn't that heavy,
if you walk around with it you barely noticed that it is there, and it keeps me save while jogging in the evening...

Enjoy the pictures....