Create your own hand-held animation using an optical illusion!

This is one of the 48 projects for our Instructables: Made In Your Mind (IMIYM) exhibition at the Children’s Museum of Houston showing from May 26, 2012 - November 4, 2012. Produced in partnership with Instructables, IMIYM is an exhibit where families work together to build different fun, toy-like projects that help construct knowledge and skills related to science, technology, engineering, and mathematics while instilling a “do-it-yourself” attitude in kids so they feel empowered to explore, tinker, and try to make things themselves. To learn more, check out the article here.

For this project, we were inspired by the Zoetrope Instructable created by Howtoons, but there may be others on Instructables that are also similar. Often, the materials and process for building our projects are designed for use with a large number of visitors (we see over 800,000 annually) and the need to ensure safety in a mostly non-facilitated environment. So, yes, many of these projects have room for improvement in both materials and methodology, which is PRECISELY what we want to encourage the kids to do. So please do share your ideas for improvement and modifications!

Step 1: What You Need

We are selective in our materials for cost, ease of use, and safety due to our high traffic (800,000 visitors annually). So, for our purposes, this design worked best. But you may have other ideas - please share!

1 – Zoetrope Template (I've included two versions below - one has a galloping horse and the other is a blank to create your own after you've created the galloping horse)
1 - Chopstick (easiest place to get them is with some Chinese take-out. However, we purchase ours in bulk from Asian Food Grocer)
2 – 1/8” x 1” Zinc plated fender washers (available at most hardware stores - we buy ours through Home Depot online)
1 - CD
Scissors
Tape

Step 2: The Video

We offer optional video segments of each step for this project in the actual exhibit. Here is a compilation of all the steps.

Step 3: Step 1 - Preparing the Strip

Cut out the two strips from the Zoetrope Template. Fold the two strips along the dashed lines. Cut out the each of the white rectangles from both strips to create the viewing slits. Use loops of tape to hold the folded sheets together.

Step 4: Step 2 - Putting the Strip Together

Tape the two sheets together into one large loop with the pictures on the inside of the loop. Do NOT let any tape fold over to the inside. Tape the outside of the loop to the edge of the CD keeping the loop as round as possible and avoiding any bulges.

Step 5: Step 3 - Assembling the Zoetrope

Push one washer over the tapered end of the chopstick as hard as you can. Place the CD onto the washer with the zoetrope strip facing up. Place the second washer over the tapered end sandwiching the CD between the two washers. Use a small piece of tape to hold the top washer to the chopstick, but do NOT tape the washer to the CD.

Step 6: To Use...

To use, hold the Zoetrope at a slight angle. While looking through the slits, spin the CD. You should see the pictures inside animate and move! If they are moving backwards, spin the CD the other direction. You may have to experiment to find the right speed to spin the CD in order to best see the animation. Also, make sure to look through the slits in the paper at the images.

The images in the animation strip appear to move when you spin the chopstick because of persistence of vision. When you look at the image through the slit, your eye retains that image for a fraction of a second after you’ve moved on to the next image. Your brain merges this image with the next one. So, as you spin the Zoetrope, the images will appear to blend and give the appearance of movement. This is similar to how flip books, televisions, and even movies work.

Now see if you can make your own Zoetrope using the blank template!