Pendulum Juggler from Philipp Reist on Vimeo.
From Popular Science:
This machine uses no sensors, no feedback -- just the power of math -- to do its tricks.
In theory, designing a robot that continuously juggles a single ball should not be difficult. Calibrating the machine would be a pain but once you got the thing running, it should continue to juggle the ball until some variable intervenes. In a perfect world, this would occur elegantly, but here on Earth things just don't come off so beautifully. However, through some smart design and precise math, researchers at the Swiss Federal Institute of Technology in Zurich have created the Blind Juggler, so named because it juggles a ball continuously, even when variables are introduced, without the use of sensors.
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