Departmental Papers (ESE)


We report on our recently achieved spatial two-juggle: the ability to bat two freely falling balls into stable periodic vertical trajectories with a single three degree of freedom robot arm using a real-time stereo camera system for sensory input. After a brief review of the previously reported one-juggle, we describe our initial approach to the two-juggle planning and control problem. We have developed a number of important refinements to our initial strategy in the course of getting the system to work, and these are reported in some detail. The paper concludes with a discussion of some data from typical two-juggle runs in the laboratory.

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version

May 1993


Copyright 1993 IEEE. Reprinted from Proceedings of the IEEE International Conference on Robotics and Automation, Volume 3, 1993, pages 919-924.

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NOTE: At the time of publication, author Daniel Koditschek was affiliated with the University of Michigan. Currently, he is a faculty member in the Department of Electrical and Systems Engineering at the University of Pennsylvania.



Date Posted: 06 June 2008

This document has been peer reviewed.