Abstract not found

Quasistatic multi-legged locomotion consists of a sequence of equilibrium postures where the mechanism supports itself against gravity while moving free limbs to new positions. A posture maintains equilibrium if the contacts can passively support the mechanism against gravity. This paper is concerned with computation and graphical characterization of equilibrium postures for mechanisms supported by frictional contacts in a three-dimensional gravitational field. For a given set of contacts, this problem is reduced to the computing the center-of-mass feasible region R, that maintains equilibrium stances while satisfying the frictional constraints. This paper continues a previous work by the authors, and provides a new method for computing the boundary of R for 3-contact stances. The paper also gives a geometric interpretations for the boundary of R, describes its topological structure, and discusses its relation with the famous support polygon principle. Finally, experimental results that validate the theoretical computation are presented. 1