Departmental Papers (ESE)


In this paper, we report on a new stability analysis for hybrid legged locomotion systems based on factorization of return maps. We apply this analysis to a family of models of the Spring Loaded Inverted Pendulum (SLIP) with different leg recirculation strategies. We obtain a necessary condition for the asymptotic stability of those models, which is formulated as an exact algebraic expression despite the non-integrability of the SLIP dynamics. We outline the application of this analysis to other models of legged locomotion and its importance for the stability of legged robots and animals.

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 1, pages 37-44.

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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