Departmental Papers (ESE)


This paper addresses the problem of registering the hexapedal robot RHex, relative to a known set of beacons, by real-time visual servoing. A suitably constructed navigation function represents the task, in the sense that for a completely actuated machine in the horizontal plane, the gradient dynamics guarantee convergence to the visually cued goal without ever losing sight of the beacons that define it. Since the horizontal plane behavior of RHex can be represented as a unicycle, feeding back the navigation function gradient avoids loss of beacons, but does not yield an asymptotically stable goal. We address new problems arising from the configuration of the beacons and present preliminary experimental results that illustrate the discrepancies between the idealized and physical robot actuation capabilities.

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version

September 2003


Copyright 2003 IEEE. Reprinted from Proceedings of the 2003 IEEE International Conference on Robotics and Automation (ICRA 2003), Volume 3, pages 3935-3940.

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NOTE: At the time of publication, author Daniel Koditschek was affiliated with the University of Michigan. Currently (August 2005), he is a faculty member in the Department of Electrical and Systems Engineering at the University of Pennsylvania.



Date Posted: 04 August 2005