Tuesday, March 4, 2008

The Torso, Abdomen & Pelvis

My first attempt at making a mannequin for C3PO wasn't successful. I had tried the very slim male mannequins (the ones with a chest size of 35), cut them down and tried to get the torso plating to fit but it wouldn't work. The problem area was with the underarm area and just the overall thickness of the body. I even tried the foam half height mannequins. The torso shell would fit only after I shaved away almost half of the body off. However, it didn't provide the structural support I needed. PVC pipe works great if you just want to hang a wearable costume but doesn't do any good if you want to animate his arms. And then 1 day I saw what Mardon had done for his 3PO and that gave me an idea. As you can see to the right he created a shelf for the neck and arms and uses a pressure fit from the torso to the pelvis area. I will probably take that a few steps further with mating PVC floor flanges on the underside of the shelf to mate with the hips and legs. For the lower section I decided to try a combination of a wood and PVC frame with foam filler to keep the fiberglass in proper position and provide stability.

I am using a CF3 for the sound system. Those sounds would be triggered by 2 methods. One would be by depressing one of the remote keys on a 12 channel RF unit from Cold Fusion. Other sounds would be triggered from a random set of selected MP3 files triggered from the motion sensor placed in his abdomen. As you can see to the right, the back of the torso has been vented for the 2nd speaker & venitlation of electronics. I used a rotozip bit to drill out the slats. As you can see to your left, I added the perl beads for the chest greeblies and restraining bolt holder. The front of the abdomen/pelvis has a hole for the motion detector that will trigger varied responses from the CF3. The back has a few slats cut in to allow a smoother mating of the torso to the abd/pelvis assembly. Later I will drill additional holes for the cable ties that will be used to hold the various wires C3PO normally has on his belly.

I just need to decide if I want to I want to power the systems from AC or DC power. I will probably run a power cord and connector to the rear left foot (the heal) in case I want the option.

Sunday, March 2, 2008

Head & Neck Section

Lighted Eyes
With that said, The first thing I worked on was the eyes. I tried to find some lighted eyes from Moncal but he wasn't making any when I needed them so I decided to give it a go. I got a piece of round stock acrylic and drilled out a center hole that happened to fit some extra 1/4" brass tubing I had from my B9 finger light build. The cross cuts to the acrylic stock eye pieces were done with a dremel tool with a cut off wheel. I found some rice lights on eBay and then I hot glued them to the brass outer ring and acrylic tube. I had to superglue them first so they would stay in place. Once that was done I put hot glue over the super glued lights. They should stay secure. The only thing I needed to get is some gold foil from Hobby Lobby to get that yellow gold light look. After I applied the foil the lights looked good. Look at the photo to the right. If you also look at the head closely you could see that I have opened up the mouth. I plan inserting the speaker behind that opening. Others have inserted speakers in the back torso vent area or in the front torso section.
If you will recall I also said that the head would move remotely. In order to accomplish this you first have to have a neck bracket made that can be affixed to a pan and tilt servo mechanism. I went to Home Depot in the fencing section and obtained a small piece of aluminum. The 2 main outer holes happen to fit the neck bolts perfectly after bending. I couldn't of asked for an easier/cheaper solution.
The pan and tilt mechanism was obtained from ServoCity.com A very simple unit to put together. The servos I used were the standard robotic heavy duty robot servos from Hitec. They are the HSR-5995TG Ultra Torque servos. The head weighs a little over 2 lbs before plating and electronic placement which is the reason I decided to go with a heavy duty servo so it should work just fine. The trick will be to fashion a neck piece that will allow a free enough movement that can be "chromed". Many have suggested getting a thick mylar "for sale" sign that can be obtained from Home Depot. I will have to experiment with that.
Once that aluminum bar is affixed to the pan and tilt support, the only thing that would need to occur next would be to build a neck support platform that would fit inside the torso. The easiest way I have seen is what Mardon did for his C3PO. He basically built a 2x4 box inside the torso that allowed to serve as the connecting points for the legs, arms and neck. Inside the head I will install (1) 2" speaker that will affix behind the mouth opening so when C-3PO talks his voice will come out of his mouth instead of his back like some others have set up. However, I will put a speaker back there as well so when he "yells" I can really crank the volume up so he can be heard in a noisy environment like a convention.