For this final example, let's graduate from a simple DC motor to a wheeled platform. There are several simple, two-wheeled robotics platforms. In this example, you'll use one that is available on several online electronics stores. It is called the Magician Chassis, sourced by SparkFun. The following image shows this:

To make this wheeled robotic platform work, you're going to control the two DC motors connected directly to the two wheels. You'll want to control both the direction and the speed of the two wheels to control the direction of the robot.

You'll do this with an Arduino shield designed for this purpose. The Galileo is designed to accommodate many of these shields. The following image shows the shield:

Specifically, you'll be interested in the connections on the front corner of the shield, which is where you will connect the two DC motors. Here is a close-up of that part of the board:

It is these three connections that you will use in this example...