I think it is great that the Rotundus GroundBot (a spherical robot) made the Popular Science "Best of What's New in 2008"; however, I'm a bit perplexed... New Scientist featured the spherical robot all the way back in early 2005; how is it "new" now in 2008? Either way, this serves as a convenient time to re-examine this novel robot -- one that brings back memories of the old solar-powered, spherical BEAM robots from Solarbotics (it was called a "miniball," and is now discontinued). Read on for some compelling images and pictures of the Rotundus GroundBot, the spherical robot.
Like I mentioned, spherical robots (that essentially shift their internal weight to provide motive force) are not a new idea. I recall building BEAM robot kits from Solarbotics quite some time ago that used the same concept, but were quite small, simple, and solar powered. For example, see the images below (from here).
However, the Rotundus (featured in both New Scientist and on Roland Piquepaille's blog back in 2005) takes this concept to an all new size scale. Add a camera and some teleoperation, and you have a novel mobility platform.
From Popular Science:
The GroundBot is a spherical sentry designed to roll up to 6 mph through just about anything—mud, sand, snow and even water. Two gyroscopically steadied wide-angle cameras and a suite of sensors give remote operators a real-time, 360-degree view of the landscape, letting them zoom in on prowlers or detect gas leaks, radioactivity and biohazards. Originally invented by Swedish physicists to explore other planets, the GroundBot features a tough design that requires almost no maintenance and can also be programmed to run autonomously. Its sealed shell protects its interior against grit and allows it to survive steep drops, while a rubber skin dampens vibration and provides traction. To get rolling, the robot simply shifts its weight. Its center of mass is suspended from a pendulum inside the sphere, so motors just push the pendulum to the front, to the back, or to the side. Lithium-ion batteries provide up to 16 hours of spy time
While the Rotundus may be a novel mobility platform, I question its application to harsh environments, especially unstructured ones such as other planets or disaster areas with lots of obstructions, let alone as a "spy robot." I'm guessing the Rotundus will remain a novelty -- though it would make a very cool toy!
Anyway, I actually think that the older video of the prototype Rotundus traversing snow was much more impressive than the more "recent" video featured on the Popular Science website (both videos are below).
Here are a few more pictures...
Oh, and just for fun, here is a video of a LEGO Mindstorms Robot built inside of a 11" plastic ferret ball based off of Rotunudus' design -- you too can make a spherical robot!