3D Zoetropes
Traditional Zoetrope
A Zoetrope is an animation machine that consists of a spinning wheel containing each frame of an animation. These can be 2D images or in my case 3D objects. If the wheel is simply spun, then all that is seen is a blur. In order to see the animation you must see frozen snapshots of the wheel as it spins. Zoetrope's have typically used slits that the viewer must peer through to give them a glimpse of each unblured frame in quick succession.
Intermittent Gear Zoetrope
I came across somebody using an intermittent spinning wheel. So rather that spinning continuously, it paused after a slight increment to allow for a brief static view of the animation frame. I loved this idea as it meant the ability to see the effect from a distance and no more peering through a slit. I tried this out on a small scale as a laser cut kit using my own intermittent gear mechanism and it worked quite well. Here is one with a little flapping bird. If you like you can get the kit or the plans to make one of these yourself.
I tried scaling this idea up to put in a café, and made a larger intermittent gear. It worked more or less, but was quite noisy due to the much heavier wheel. It was difficult to get the speed up. I decided to try the strobe light method instead.
Strobe Light Zoetrope
Another way to avoid having to peer through a slit to see your animation is to use a strobe light. The light flashes after each partial rotation to give you a snapshot view of the animation frame. I wanted to avoid this method as it requires a dark room so that you can't see the animating objects when the strobe light is in it's off state. A way around this is to use a tinted screen over the animation. This means that the ambient light can't get in and illuminate the sculptures so that they truly flash in sequence rather than blur past. I live in Tasmania Australia so I thought a Tasmanian devil would be an appropriate subject. I sculpted the devil in Blender which is a free 3d animation software with great capabilities. You can sculpt the object as a mesh, and then give it a skeleton (rigging) to push the mesh about. You can then animate the skeleton and save out a 3D stl file for each desired frame in your zoetrope. I then 3D printed the eight frames of the devil head in his various mouth opening positions. I sprayed them with automotive etch primer before painting.
You can see little knops around the wheel. These engage a micro switch as the wheel turns in order to turn the light on and off at the correct times. Ideally my lights would have been further out to illuminate the sculpture better but the box I made was not deep enough. I may make a lower profile animation to fit inside this box.
The effect works in a bright room due to the tinted screen, but is clearer in a dark room, and best in a spot where there are not too many reflections on the view window. This Zoetrope is now up on the wall in the local Bakery in the hopes that one day it might buy me a coffee.
One thing I was quite happy with was the coin triggering method. I finally seem to have got one that works every time without fail. I will do another blog post on this some time. It is basically a slide with rails that connect a circuit to trigger a timer. This Zoetrope is bit of a difficult thing to film. Unless your final video is a high frame rate you can end up with missing animation frames in your video. There is a video of it running at the top of this page.
Things to try next
For future zoeptropes I will try a faster motor. This one spins the wheel at 50rpm which gives about 7 frames per second. 10 frames per second would be better. I would also try to improve the direction of illumination and perhaps have some way for people to see the inner workings, as at the end of the day, that is what we all really care about.
These are fun things to make. If you would like to make a purely mechanical zoetrope with the intermittent gear method, you can get the kit or the laser cutting / scroll saw files here