Virtual Wedging in Three-Dimensional Peg Insertion Tasks

Abstract

Quasi-static wedging of three point contacts is investigated, wherein the concepts of virtual and redundant wedging due to a resultant force falling into a frictional cone are proposed. We consider the fully started case of a square peg and hole consisting of two point-surface contacts and one line-line contact. An analysis of the wedging diagram for this highly constrained configuration is carried out and compared to the two-dimensional case. An approximate wedging diagram is constructed which shows that wedging of square pegs into square holes is more likely than cylindrical pegs and holes of similar sizes.