How the Sphero works
Sphero 2.0 is the world’s first robotic ball you can control from a smartphone or tablet. It has over 25 apps available for iOS and Android, ranging from games to tools and lighting, and the device is cram-packed with tech. But with a sealed shell and no apparent moving parts, how does it roll? It all starts with inductive charging. In order to keep Sphero waterproof there can be no plugs, wires, or battery compartments. Instead, it has its own built-in batteries that are charged by passing energy through the shell itself. This is accomplished by a charging station containing a copper coil, which generates an alternating electromagnetic field. Inside the robot another copper coil converts that invisible field into electricity.
Once charged, a quick double-shake of Sphero is the command to ‘wake up’. This is when all of the robot’s electronics turn on, including its coloured LED lights, CPU and Bluetooth communication module, which allows it to talk to your smartphone. When a user starts the Sphero Drive app and touches the joystick, that touch is converted into a given speed and heading, which is then conveyed to the robot via Bluetooth. Sphero then rolls wherever the user directs it on their device.
Carefully packed inside the white shell is a tiny robot that uses a gyroscope to balance on two wheels. Think of it like a Segway stuck inside of a ball. Sphero might not look like it has a front or back, but the robot inside does thanks to the help of a gyroscope. When Sphero is commanded to drive in a new direction, it’s able to rapidly rotate to face the right way based on its position relative to the user. This all happens seamlessly inside the robot. To the user, Sphero rolls just like any other ball.
But, how does Sphero drive? In short, it drives like a hamster wheel spins. The robot drives up the side of its own shell just like a hamster runs up the side of its wheel. Of course, the hamster never gets anywhere. No matter how hard it tries to climb, gravity pulls it down and the wheel falls away beneath it. Sphero works the same way – constantly climbing uphill, scrambling up the side of its own shell only to have the shell roll out from under it – which causes Sphero to roll. In a sense, Sphero runs on gravity.
You can learn more about Sphero at www.gosphero.com.