Hey Guys! So this is the biggest project I've worked on so far, combining all my construction, electronic and painting skills. I had an absolute blast making this guy, I learnt so much during this project and want to share with you how I did it. You can also find this instructable on my blog where viewing images might be easier :) http://propsolve.blogspot.co.uk/2015/11/robotic-wheatley.html
Step 1: Cutting the Foam
Before I begin I'd just like to mention the folks who have also made a Whealtey and give them a massive thank you! They were a huge help in the making of my Wheatley. Here they are:
Luke Albertson, he made a freaking awesome animatronic Wheatley: https://plus.google.com/116390055317219768340
Furin Cosplay also made an epic Wheatley puppet:http://furincosplay.blogspot.co.uk/2011/07/wheatley.html
I wanted to make my Wheatley with the most non-toxic materials as possible, although this made things trickier I wasn't exposed to any nasty vapors/gasses/harmful particulates which I count as a plus ;) Okay so now for the first step. My first step was creating the initial sphere for Wheatley's body. I chose to make this from blue foam, also called insulation foam or blue polystyrene or XPS foam, there are a lot of names for it! I found this method for making a sphere and It worked out pretty well for me :) https://www.instructables.com/id/Make-a-Foam-Spher... cutting out the circles of foam I use a thin stanley knife, I found that this gave me the cleanest cut and the thin blade made it much easier to follow the cutting line. To help the blade cut through the material I used the wax from a candle to lubricate the blade fairly frequently. I used UHU Polyurethane glue to stick the circles together, I could have used expanding polyurethane glue, but this out gasses some pretty nasty stuff so I stuck with the UHU (Be warned through, UHU is a pain in the butt to sand!)
I messed up the first time I tried to make the sphere by making each circle too small, the turret on the right is the one I messed up.
Yay! We have a sphere!
Step 4: Cutting Out the Detail
The Next step was cutting out the detail. I used a floppy tape measure (Technical Term) to measure out the lines that needed cutting. Before hand I drew a 1:1 scale drawing of Wheatley which I used to get all the measurements right. I used my dremel, stanley knife and an assortment of other weird and wonderful tools to cut out the detail.
Step 5: Oops!
Dremel Safety Kids! Don't get your hair caught in your dremel.
Step 6: Paper Mache Pulp
After I had carved out the detail I then split the sphere into two. I needed to strengthen the foam A LOT, I used paper mache pulp for this and used this recipe :https://www.youtube.com/watch?v=f84FvxLHCnk This woman is crazy talented, check out what she can do with paper mache here! http://www.ultimatepapermache.com/
I could have used something like fiberglass or Wonderflex instead of paper mache pulp, but budget and safety constraints did not allow for this.
Step 7: Pulp Malfunction!
There was about a 4 day gap between me covering the other half as I was busy with other stuff, I had put the pulp in an air tight container and it seemed pretty sticky when I put it on, however it did not work and just started peeling off as it dried, damn! So I had to make another batch and paste it on,
Step 8: Sticking Spheres Back Together
After this, I used foamed pvc strips and stuck them to either half of the sphere to stick them both back together.
Step 9: Strengthening the Outer Shell
After this, a lot of Milliput epoxy putty and sanding was needed. The two halves didn't meet perfectly so I used Milliput putty to even them all off. Milliput is amazing stuff, it comes in two parts and once the two parts have been mixed together you have about 4hrs until the putty sets completely. Before it sets you can shape it very easily, if you use a damp pallet knife and skim across it's surface you can achieve a really smooth finish. Once it has set it sands beautifully and can be painted over very easily too. To strengthen the outside I used Rosco Foam coat, again I could have used something like bondo or EpoxAcoat, but went for the non-toxic material instead. This stuff is also really great, I applied it with a big brush then went over it with a damp sponge before it had set completely. It does not give you a particularity flat surface and so LOTS of sanding is needed. I covered the sphere in about 5 coats, sanding in-between each coat. Sanding is one of the longest (and most boring) processes you'll go through when making something like this, unfortunately it just can't be avoided.
Step 10: Electronics
While this was going on, I was working out all the electronics. This was the longest part of the build and because I had no experience with servos, programming or any electronics training at all, it took me a while to figure it all out. I began my buying the Arduino starter kit (and yes, I'm that much of a noob) This really helped me understand the basics of programming and electronic principles. For the eye lights I used the Velleman sound to light kit (Thanks to Luke Albertson for this idea) I hooked this up to the 3 5mm LEDs in the center of the eye and also directly connected it to my speaker so It would only react to Wheatley's Sound. For the lights around the edge I used 5 leds wired in series and just hooked them up with a 9v battery (with the appropriate resistors of course) For the head movement I used a pan and tilt kit with 2 TowerProp MG 99 Servos. For the eye lids I used 2 SG90 9g Micro Servos, these were programmed to move at the same time (I'll post my sketch down below) For the sound I used an Adafruit sound board hooked up to ten buttons. The Head and Eye lid servos were both connected to 2 joysticks.
Step 11: Eye Light
I used a lot of parts form a torch I found for the outside part of the eye. I used Photoshop to create the hexagonal blue eye plate. I printed it out on tracing paper and stuck it to the clear plastic of a cd case (I had cut this to size using a plexiglass cutter and lots of sanding)
Step 12: Eye Light
Here is the front of the plastic cd case cut to size with double sided sitcky tape stuck on top ready for my photoshop eye plate.
Step 13: Eye Light
I placed The 5 LEDs that go around the center and the 3 center LEDs in some large cell foam that came in a package I had ordered. This stopped the LEDs from moving around and also diffused the light. This was then placed inside the black ring that I had found from a torch. The torch also had a dome shaped plastic cover which I used in the front of the eye.
Step 14: Eye Light
Here is everything sitting inside the torch casing. I dont have the center lights switched on in this picture, but ya get the idea :)
Step 15: Eye Plate
I carved the eye plate out of blue foam. I used strips of foamed PVC and fit them around the inside circle and around the outside to give me a stronger edge, It also helped to achieve a better circle.
Step 16: Attach Eye Plate to Servos
I found that the best way of attaching the eye plate to the servos was by using mecanno. As it was held together with nuts and bolts It allowed me to keep tweaking the placement of the eyeplate. If I had used glue it would have gotten very messy.
Step 17: Eye Lid Servos
I don't have many eye lid process pics, but I basically used two servos, and attached the eyelids (which are made from foamed PVC bent to shape) to a wire which are attached to the servos. This took so very very long, The eye lids kept catching on the eyeplate and the eye and the wires kept breaking and it was just a very big pain in the butt. However after much fiddling I got them both to work. (The picture you see only has one servo attached)
Step 18: Electronics Pics
Step 19: Embroidery Hoop
Back to Construction (Yay!!) I needed the front and back openings to be perfectly circular, I took a leaf out of furin's book and used some embroidery hoops, they worked like a charm! I hot glued them in and cut out the center parts. I then had to bridge the gap between the embroidery hoop and the edge of my initial sculpt so I used Milliput, this worked really well (after lots of sanding of course)
Step 20: Creating Platform for Servos
So the next step was to create a platform for the servo tower to sit on, I cut some wood to size so that it would fit over the center section, I used milliput between the wood and the inner shell to achieve a perfect fit and create a better gluing surface. I then glued another piece of wood exactly in the center on top of this. Then I attached a servo holder to the top of this. I wanted to paint the inside black however the surface was quite rough so I covered the inside with paper mache (newspaper strips this time) as this added extra strength and also created a smooth surface.
Step 21: Painting
I only have two pictures of the painting process, I'm very sorry guys! The first coat was a light grey, I then mixed some iridescent medium (It gives the paint a metallic finish) in with the light grey paint. I then dry brushed and and paint flicked to make Wheatley look nice and dirty :)