November 5, 2011

DIY Daft Punk Helmet

 For Halloween 2011 I was just about to give up on making something new and just go with an existing costume when I saw a gadget blog post for Volpin Studios Daft Punk Helmet, both the helmets Volpin has built are impressive but the Thomas one looked amazing to me when it was finished.  While I am not the biggest Daft Punk fan, I knew instantly this would not only be impressive to complete, but also be a lot of fun with the required electronic engineering.  With a final costume idea in mind and about 6 weeks of time before halloween I set off on another crazy DIY project.  In the end, while the helmet was not as perfect as others, the electronics made up for it and everyone who saw it give me the thumbs up. (See the build video at the bottom for more pictures)

Fist off I did a lot of research into how other people have made helmets.  Besides Volpin, tekparasite also had interesting build ideas and a lot of documentation.  Between them, many youtube videos and forums, I had more then enough information to plan out what I wanted to do.  Basically it boils down to three options for the helmet itself. There are high end solutions involving casting and molds, which have amazing results, but take too much time and would cost a lot.  Then there is the option to buy an existing mold, saving a lot of time, but still costing a lot.  Finally there is the cheap way of using cardboard and/or other helmets as a base.  I decided that my goal was to go with the cheap option and make the best helmet I could for around 50-60$, the end cost was closer to 75$ but I now have a lot of extra parts for future projects from buying things in bulk, so it was acceptable.

To get started I needed to get a helmet shape, to do this I searched for existing paper craft models I could use.  Luckily it was not hard to find one.  After getting the required programs to view and print the models, I had a pdf containing several pages of shapes to cut out.  I knew right away that the base size would not be large enough, so after creating a scale helmet and trying it on, I estimated that 110% scaling would cover the size I needed while not being too huge.

Next, I printed and cut out the pieces that I had rearranged and scaled in PhotoShop.  Then painstaking glued and re-cut them out of cardboard.  This gave me a sturdy base that I could build on without having to rely on fiber glass like most paper craft builders do.  I grabbed my glue gun and assembled the pieces and ended up with a base helmet that fit nicely but had room of the parts and pieces that would come later.  Because I skipped the ear pieces I cut two large round circles of cardboard and placed them inside the helmet to fill the empty spots.  Then using two soda cans I crafted the ears by bending cardboard in a ring.  Later soda can ends and plexiglass would cove the ends.

After crafting the helmet skeleton I took Bondo and smoothed out the cracks and blockly-ness of the paper craft base.  After letting it dry, I sanded for several hours with a rasp and various levels of sandpaper. Once that was round and smooth I repeatedly used a thick layer of white acrylic paint to further fill in spots, and then re-sanded.  Finally two coats of glossy black paint gave me the base helmet I needed to move on to the fun electrical parts.  (Time: two weeks of nights and weekends)

In between waiting for things to dry I created a set of gloves from black work groves and milk carton plastic.  This was covered by metal duct work tape and hot glued to the gloves.  I based the shapes off of Volpin's glove template and then adjusted it to fit a scanned trace of my hands.

Next came the part I was looking forward to.  I had already ordered 500 3mm red leds, 10 MAX7219CNG chips and other assorted leds and parts off of ebay before starting work on the helmet as I knew it would take 2-3 weeks to get them from China.  By the time I had the helmet ready everything had arrived.  I used my heat gun to bend a strip of plexiglass into shape and then carefully drilled 256 pairs (that is 512 individual holes!) using a 1/32 inch bit.  A rotery tool or drill press would have been nice, but a hand held drill got the job done without any accidents.  I used a paper template to mark each hole before drilling.  Then I trimmed and soldered each red led into vertical column, then after completing each column I would bend the annode and connect it to the previous led in the row.  This created groups of 64 leds, the cathode wires holding in the leds vertically and the annode wires holding the group together in rows.  After finishing each group of 64 I used some spare ribbon wire to build the connectors.

Each of the four groups had two connectors and which went to a separate MAX7219CNG soldered to a protoboard. Each board and headers where custom designed and hand soldered.  I could have ordered a custom PCBs, which would have shaved several days of work off, but that would have cost a lot more, so in an effort to keep the build costs down I did everything by hand.  There is a lot in information on using the 7219 chips with arduinos and the Led Matrix library does most of the hard work for you.  On the hardware end, basically they are chained together and require a resistor and two capacitors, beyond that it is just a matter of connecting the right pins to the right led row.  Once that was finished, I connected everything tested out a few patters and attached the array to the inside of the helmet.  Using some night shade car tint spray and another bent piece of plexiglass, I had the helmet all covered and almost finished.

The final parts where the ear and side lights.  Using a separate fifth MAX7219CNG, I created 4 led  protoboards (two for each side/ear), the side lights where directly connected back to the 7219 board and the ear lights had separate headers as they needed to be threaded through a slit in the cardboard.  I mounted the side lights and build a little reflective holder that would defuse the bright leds of the colored rows.  Next, I had to cut out and round some plexiglass by hand to match the ear shapes.  The ends of soda cans covered the plexiglass and ear leds.  Then I masked off each exposed plexiglass piece on the helmet with masking tape and gave the entire thing a final coat of  rustoleum metallic spray paint.  Once again I could have worked out some form of chroming as others have done, but chroming along would add $100+ to the build price.  The metallic paint actually looks quite good despite laking the complete mirror reflection, the only issue is that it needs light spray passes, takes several days to dry, and can still be dulled by touching even after dry.  I just used the ears to put on the helmet, which kept the dulling in one place and avoided touching the main body as much as possible.  The lights tend to distract people anyway so it is not much of a problem unless you plan to wear this all the time. (Time two weeks of nights and weekends)

The final touches where the power supply and the programing.  I used a pololu power regulator as it covers the amperage requirements and could be reused as a breadboard power supply.  For the power supply, 8 AA batteries supplied 12v  to the regulator and where still ok power wise after all the Halloween festivities where over.  Then I wired up an arduino to all of the MAX7219CNGs and also to a separate row of three buttons that I could use to switch patterns. The arduino sketch can be found here.  It was interesting as I figured out a nifty way to use a array of vertical 8 bit char and then bit shift them into rows based on an offset, this let me create a quick java program to visually create the patterns and then enter the numbers into the array.  A few patterns needed special handling code but most where covered.  I have to give tekparasite extra credit, as while I had a few animations in mind I was looking for extra example from the actual Daft Punk helmets, he had actual videos of many very creative choices, some of which I included in my build.  (See video below!)

The end result was everything I expected.  The helmet had a few cosmetic inperfections here and there, but looked fine over all and the light effects made sure no one noticed right away as everyone was too busy watching in surprise.  I also believe I get some partial bragging rights as unless someone has not posted their project, this is the first DIY helmet to include all four working light sections (front, both side parts and ears) and be on youtube/blog for others to use as a reference.  Both Volpin and tekparasite who have have impressive helmets (with actual crome finish) where missing one of the four in the end result videos that where posted.  Hopefully this will inspire others to not give up due to cost and make budget restricted but still functional helmets in the future.