Willow Garage’s Pool Shark team has programmed the PR2 to play pool, in what they call a short hackathon sprint.  Using a special bridge and grip, to allow it to power shots with wrist motions, its high resolution camera combined with a color blob tracker to find the balls, and the FastFiz open source pool-physics library, by Alon Altman, to check planned shots before executing them, the PR2 has become a pretty good pool player, the occasional scratch notwithstanding.
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