Patent ID: 7303063

Claim:
A step-and-repeat mechanism for moving a work surface across a support surface, the mechanism comprising: a rigid sphere having six legs extending radially along three orthogonal axes, each of said legs having a distal end, said distal end having a convex surface, a holder for retaining said sphere in a fixed location relative to the support surface, a work surface disposed on the support surface, said work surface having an array of upwardly facing dimples, each dimple having a concave curvature corresponding to said convex surface of said distal ends of said sphere's legs, means for sliding movement of said work surface across the support surface, said sphere rotatable between a first attitude and a second attitude, in said first attitude a first set of three of said distal ends of said legs indexed in a first set of three of said dimples of said work surface, and in said second attitude a second set of three of said distal ends indexed in a second set of three of said dimples, means for application of sufficient force to at least one of said legs to move said sphere from said first attitude to said second attitude, such that said work surface is moved from a first horizontal position to a second horizontal position.