Deployable Structures Based on the Bricard Linkages

Abstract

*† In this paper, we explore the possibility of forming large deployable structures using a particular type of the Bricard linkages: the three-fold symmetric Bricard linkage. The characteristics of this linkage are that, first of all, all of the six links have the same length and they are connected by revolute hinges; secondly, the skewed angles of the adjacent joint axes are α and α 2π − , respectively; and finally, there are no offsets in each joints. Based on the governing compatibility equation of the linkage, we obtained the compatibility paths. It has been found that if the skewed angle is π/3 degrees, the linkage can be folded completely to a bundle and expanded to a planar equilateral triangle. This particular feature makes the three-fold symmetric Bricard linkage a good choice as the basic mechanism for the construction of deployable structures. A scheme of distributing the basic mechanisms by repetition has been identified which can be used to form the large deployable structures with a single degree of freedom. The concept has been successfully verified by physical models.