Patent

Magnetic spherical balancing robot drive

Inventors: Lanny Smoot , Dirk Ruiken

Original Assignee: Disney Enterprises, Inc.

TL;DR

The first thing we have learnt from this patent is that there is a concept in robotics called holonomic motion. Ground-based holonomic robots are those who can instantaneously move in any direction on the horizontal plane. That makes them incredibly responsive. Both the Sphero and our little guy BB-8 are holonomic robots.

The patent presents several variants of the invention, but one of them is suspiciously similar to BB-8. According to this configuration, the body contains a drive system that always keeps a relative position with respect to the sphere. The system uses omni wheels to make the sphere roll in any direction. Each of those wheels is connected to a motor. The robot uses sensors (gyroscopes and accelerometers) to determine its position and dynamics. The drive system can be maneuvered using a remote controller. The base plate acts as a counterweight, keeping the center of gravity close to the ground. That keeps the wheels' traction on the inner shell of the body. So far pretty similar to the Sphero.

The main difference we find with the Sphero is the dynamic mast described by the patent. There is also a control system that keeps everything in balance, making sure the mast is always in vertical position. This, if you think about it, makes the whole mechanism behave like a miniature Segway. The arm can rotate and, according to the patent, magnetically interact with an external element. That means BB-8's head is most likely controlled via magnetic interaction. Magnets at the end of the mast and roller magnets at the base of the head.

Now let's use some 3D to show how the inner mechanism of the cutest astromech in the galaxy might look like.