Gray Fox KAI
So, after 3 years of having debuted the original Gray Fox costume, I got the itch to finally remake it by first engineering every aspect of the helmet completely before even making the first piece.
When I made the first version, I only needed an approximation to the shapes, and I left everything else to manual workmanship, including positioning the servos, kinematics and wiring. I originally wasn't intending on adding servos to actuate it. It was supposed to just be hinged and use magnets to hold it in the closed and open position. In hindsight, the way the 4 bar linkage ended up working in the original version was a streak of luck.
This time I wanted to make sure everything was 100% defined on the computer first.
So I started by taking a 3D scan of my head, while holding a ruler for later scaling. This was done using Autodesk's amazing free software 123D Catch.
123D catch window
After scaling, I brought in the mesh into Meshmixer, another free program by Autodesk (Now would be the time to mention how awesome Autodesk is with their free software!) Along with my head mesh, I brought in a Gray Fox model ripped from Metal Gear Revengance. I put the two together and scaled the Helmet roughly until it made sense and wasn't too big on my head.
My head and the ripped model prior to scaling the head
After I had a satisfactory scale, I brought in the geometry into Inventor and, using it as reference, started surface modeling the helmet.
This step took several attempts and lots of frustration, as well as lots of learning. In the end, I had a surface I was pretty happy with and which could thicken properly. I won't go into detail as to how the surface modeling took place, but I'll publish a video summary of it later.
Once I was happy with how the surface model turned out, I added all the details, including segmenting the helmet into its separate components, and then worked out the kinematics for the opening and closing. I modeled the lenses, diffusers, and even made chamfers for the parting lines
I got some models for the LEDs as well as the arduino trinket from grabcad, an amazing community of designers and engineers that upload their models for other people to use. Membership is free as well. I designed I also looked for some servo models that matched what I'd used in the first version, but upon not finding them, I modeled my own and added them to the grabcad library.
The rest of the hardware models I used, I downloaded from mcmaster carr, since I will then order it from there.
Once all the pieces were in place, I made a drawing of the assembly so that I could get a better sense of what the bill of materials would be, as well as because... prints are awesome.
drawing of the exploded view. I took some liberties and played pretend with the drawing manufacturer approval.
Last, but not least came the wiring. I did this mostly as a way to learn Inventor's wiring tool, but it turned out to be a lot easier than I expected. Everything is wired properly in the model, with the correct pins from the board matching the power supply, lights and servos. In theory, I can now assemble the wire harnesses before the parts arrive, and simply attach them after they arrive.
Now I have a friend of mine checking my work and making sure I didn't miss anything.
Next, I'll 3D print the parts, do some surface finishing on the prints and then make some silicone molds.
Thanks for reading!