As part of our Halloween "Harry Potter' theme this year, I wanted to make an animatronic Fawkes. Fawkes is one of my favorite characters from the Harry Potter series (and my costume is Dumbledore!)
The movement is based on two servo motors--one to turn the neck and one to open and close the beak. The servos are controlled by an Arduino board programmed so that the neck and beak move in a random order.
I got some great inspiration from this site http://www.socalhalloween.com/Project_Raven.html, although his animatronic raven has many more degrees of freedom than Fawkes does.
Step 1: Materials
The body is based on a plywood cutout bulked out with foam.
The legs are 3/8" diameter aluminum tubes.
The feet are sculpted from black Fimo polymer clay, and were sculpted in-place around the perch.
The neck is a 1/4 in diameter aluminum tube attached to the neck servo on one end and the head on the other.
The head is again, based on a plywood cutout bulked out with foam. The eyes are glass beads, the beak is sculpted from Fimo. The upper beak is fixed; the lower beak is attached to the beak servo.
The skin of the bird is thin batting covered with a cloth mesh wide enough to poke the quills of the feathers through. Feathers were hot glued to the mesh. A wide variety of feathers are available on-line or at fabric or crafts stores.
The base and column of the perch is an old floor lamp. I cut the perch support from pine stock. The perch itself is a 1.5 in diameter dowel. I couldn't find any pre-made finials, so I turned the two finials and painted them gold.
The electronics: Two hobby servos: Hitec--a standard size for the neck movement, a micro servo for the beak. An Arduino Duemilenova microcontroller board controlled the two servos.
Step 2: Building the Perch
I used an old wooden floor lamp stand as the base of the perch. I cut a semicircular piece out of pine stock to act as the support for the perch itself. The two 3/8-in aluminum tubes which serve as Fawkes's legs are inserted into holes in the perch and glued into place. The wiring is threaded down one of the bird's legs into the perch and down the stand to the floor.
Step 3: Sculpting With Polymer Clay
Fawkes's feet and beak are sculpted from polymer clay. The top part of the beak was built up on the plywood used to outline the shape of the head; the bottom part of the beak was built up on an extension of the horn attached to the beak servo. I could bake both of these pieces in the oven to cure. Because I wanted to sculpt the feet around the perch dowel and aluminum rods serving as Fawkes's legs, I could not cure these in the oven, but rather cured them by a long slow process using a heat gun. Not optimal, but it works, and it especially helps if you have a thermometer with which to monitor the temperature near the part being cured. I found it was easy to overheat past the 265 F curing point of the clay, so it required some careful tending to, and lots of time.
Step 4: Building Up the Body and Head
The body is based on a piece of plywood cut to the outline of the body with cut-outs for the neck servo and aluminum tube which serves as the neck shaft. I bulked out the body with pieces of black foam packing material which I found was easily cut with a small saw or scissors and didn't shed pieces like styrofoam. The leg tubes were inserted into wooden blocks attached to the plywood body base.
The head is based on a similar piece of plywood with a cutout for the beak servo. To attach the head to the neck shaft, I cut and flatted the aluminum tube to fit around the plywood. After aligning it to look natural, I screwed the flattened tube into place. The lower beak was attached to the servo. The glass beads used as eyes were glued to wooden blocks attached to the plywood head base to give them the proper spacing. The spacing of the eyes, I found, dictated the width of the head. The head was then bulked out with the packing foam as well.
Because the lower beak needed to be on the center line of the head, and the servo attachment wasn't, the lower beak attachment was made to a piece of metal attached to the servo horn. The metal was bent to make the transition from the servo placement to the center of the head where the beak fit. This can be seen in the picture of the entire framework below. A little black paint to camouflage the metal color and it blended in well beneath the feathers of the face.
Step 5: Programming the Arduino to Control the Servos
Although the programming to control two servos is fairly easily accomplished with the Arduino controller, I hadn't done any programming in, oh, 25 years, and that was in BASIC. Still, there is lots of good information on the Arduino site with patient tutorials and lots of example programs, and I managed to figure it out fairly quickly. I also wanted to add in a bit of randomness to make Fawkes's motions look less robotic which made the program more complex.
Basically, the program flips a coin and if it's heads, it moves the neck back and forth a couple of times. If it's tails, it waits 2 seconds, then flips another coin and if that one is heads, it opens and closes the beak. Then it waits another 2 seconds and goes through the loop continuously. This way, there could be rather long times when Fawkes doesn't move, but other times when he moves his head and beak in a random order. The code is in the file below.
I used a separate 9V battery to independently power the Arduino once the program was downloaded into it. Pins 9 and 10 of the arduino are used to control the angle of the servos. A 6V battery pack (4 D cells gave plenty of power to run all Halloween night, although 4 AA cells might have been enough.) The servo grounds are tied to the arduino ground. The Arduino and the batteries were fitted into a box which rested on the floor by the base of the perch.
Future features would be to randomize the neck movement speed and angle more, as well as changing around the beak open and close speed.
Step 6: The Skin and Feathers
Once Fawkes was programmed and moving correctly, I started making him look more Phoenix-like. As skin, I used thin white cotton batting which was like rather thick and more flimsy felt. This was cut to fit and tacked in place with a hot glue gun. Over this, I added a layer of red mesh cloth with mesh size large enough to stick the feather quills into.
Now, the fun starts. Up to this point, I had thought debugging the programming was the most tedious part of this project, but compared to gluing Fawkes's feathers on, it was nothing! Starting at the tail end, I layered on red feathers on his sides and back, varying it with a mix of yellow, tan, and brown feathers on the chest. The wings were separate cardboard cutouts that were covered with cloth as the body was and feathered on the side away from the body. The wings were attached separately after most of the body feathers were glued on.
The head was particularly fussy to get right as I wanted the feathers around the beak and eyes to look fairly natural. I think I got it pretty close. I was a bit worried how the feathers would react when the head moved, but they move pretty naturally I think. Fawkes has a few feathers sticking up out of the back of his head, and long tail feathers as well which were added at the end of the feathering process. I was lucky to be given a couple of red macaw tail feathers which worked perfectly for Fawkes.
Step 7: Fawkes's Debut on Halloween
Fourth Prize in the