Wednesday, January 9, 2013

Whirly Birds - study in hydrodynamics and biomimetics

I know. It's a mouthful, isn't it? But it's a really fun project for kids of all ages. I did this experiment in 5th grade class yesterday, and it went well. But, it took much longer than I expected. I started with 6 designs, but I will cut that down to 3 designs in next week's experiment with a 1st grade class. I didn't realize how long it would take to cut these out.

An important disclaimer first. I got this project ideal from science buddies. Please check out www.sciencebuddies.com. It's a great place to go for project ideas.

Before I started the project, I discussed the concept of biomimetics or biomimicry. Simply, it means that engineers are trying to use what we find in nature to improve functions of man-made objects. A great example is velcro. It was invented by a man who went for a walk with his dog and came home with a lot of hooked burs from the local hills on his socks and his dog. He studied the burs and invented velcro. Imagine that!

This is the procedure for the experiment on science buddies. You can follow this or follow my instructions listed below.

Whether following the science buddies instruction or mine, it's good to read the background info.

Biomimetics - Studying and Learning from Nature

I start this class by talking about bumps on humpback whales' fins, shark's spiky skin, and tiny fins on mackerels. All this info is on the background info. I continue the discussion by asking the class if any of them were lazy or their parents call them lazy. Then I tell them that nature is also lazy. It doesn't want to do any more than it has to (in most cases). So, if they see something that doesn't make sense, they should investigate it because there's a reason for that feature.

Supplies:
1.      Paper, to copy the whirly bird designs on them. I've used two different kinds of paper in class (plain copy paper and construction paper), but I've also used card stock paper at home with my children to see the difference. It really doesn't matter for the lesson.
2.      Craft scissors for make patterns. It would be nice to have scalloped and saw-tooth designs, but this is not a must have. Any sharp vs. curvy pattern would do.
3.      Pencil and notebook paper to take down data.
Instructions:
1.      Ask which features were represented by which scissor designs. Sharp - shark skin/mackerel finlets. Curvy - tubercles on whale fins.
2.      Ask which edge would be most efficient. It's supposed to be curvy, but it wasn't a clear cut winner in our experiment.
3.      Follow science buddies instructions on cutting and making whirly birds. Here are some pictures.
4.      With a classroom of 33 kids, even dropping 6 design 5 times each was hard to complete in 90 minute class. So, I'd stick with the 3 designs. Now, if you're doing this at home, I'd say try all kinds of paper and craft scissor designs.
5.      After the experiment, ask if they could think of five different uses for their biomimetic findings. My classroom of kids came up with a thin skin to cover over boats, torpedoes, etc. to make them slice through the water more efficiently, to name a few.
6.      The key concept to talk about is that nature is lazy. There is a reason for most of the natural features on animals, plants, insects, and the students should investigate them.
Have fun!