Departmental Papers (ESE)


We review our progress to date in eliciting dynamically dexterous behaviors from a three degree of freedom direct drive robot manipulator whose real-time stereo cameras provide 60 Hz sampled images of multiple freely falling bodies in highly structured lighting conditions. At present, the robot is capable of forcing a single ping-pong ball into a specified steady state (near) periodic vertical motion by repeated controlled impacts with a rigid paddle. The robot sustains the steady state behavior over long periods (typically thousands and thousands of impacts) and is capable of recovering from significant unexpected adversarial perturbations of the ball's flight phase. Gain tuning experiments corroborate our contention that the stability mechanism underlying the robot's reliability can be attributed to the same nonlinear dynamics responsible for analogous behavior in a one degree of freedom forebear. We are presently extending an algorithm for simultaneously juggling two bodies developed in that earlier work to the three dimensional case.

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version

May 1992


Copyright 1992 IEEE. Reprinted from Proceedings of the IEEE International Conference on Robotics and Automation, Volume 1, 1992, pages 775-780.

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NOTE: At the time of publication, author Daniel Koditschek was affiliated with Yale University. 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.