Exercise 1: Mad Mehcanisms


Electric motors are used in so many places and whenever you see them you'll also see mechanisms. Mechanisms, put simply, are needed for changing how a motor moves. Mechanisms can for example slow down or speed up some movement, make something that rotates move back and forth or change the location of the movement. You can use gears, cranks and joints in mechanisms but with a little bit of imagination you can make mechanisms with pretty wild materials. In this exercise you'll grab a servo and create a simple mechanism. Here's a few ideas you can explore. You don't have to make a useful project. It can be something just for fun, too. But of course you can start off with a practical problem you want to solve. Think of a wide range of things you can do with the servo movement. It could draw, mix, play sounds or open something. You could make this into a challenge, too. What's the biggest movement you can create with a small servo like this, how big can you go? Or what if you have to make a moving robot with just one servo? See who can make the best crawler robot. You can try to link moving parts together and use everyday materials to test your ideas, too. And by the way, does the servo have to be visible? Often it's pretty nice if you can hide the motor completely. Use some of these ideas or follow your instinct. Start with the program you made earlier in this chapter. Change it if needed. Control the delay with sensor values or program new movement patterns. If you have different switches at hand you can use those instead of a button, too. Just keep it simple enough for now. You can always continue with these ideas later on.

Do this

Develop a simple mechanism! What kind of movement can you create with only ONE 180-degree servo motor?


  • make a little robot that crawls around. 
  • think about what you can open, shake, throw, swipe, hit, play or scratch with a servo. Collect simple crafting materials and create that movement!
  • Try out a mechanism from the video above!

Keep it simple: it doesn't have to be a unique idea! Give yourself a time limit of 15-20 minutes!

Different materials for attaching stuff to the servo motor

Educator notes

Example: A small toy hack

The mechanism can be very, very simple and it should not take long to make! Here's a little example of what's possible to make in 15-20 minutes.

1. A piece of insulation foam / styrofoam is great for fitting the servo inside a toy.

2. A cork extends the movement range. Use a piece of wood (popsicle, barbecue stick) instead if you like - hot glue keeps it nicely in place.

3. Fit everything inside a toy!

4. Fine-tune the Arduino program. LED lights have been added here for extra effect!

Workshop video by Niklas Roy and Kati Hyyppä is nice for inspiration (released under Youtube Creative Commons licence CC BY)

Mechanisms are a fascinating topic to explore further. For a practical, creative approach, check out the book Making Things Move by Dustyn Roberts. Many of the techniques introduced in the book can be applied to Arduino projects, as well!