结合四面体旋转环机构和三向对称六连杆机构的基本原理,设计了一种向外翻转开启式可展结构.这种结构以6个四面体构件形成的三向对称环形连杆机构为基础,通过四面体绕相邻铰转动实现结构的闭合和开启.详细阐述了该可展结构的形式和设计原理.当结构的支座向结构中心轴方向运动时,结构向外翻转逐渐开启;相反,当支座远离结构中心轴方向运动时,结构向内转动直到相邻四面体的面相互接触而闭合.从结构基本几何参数出发确定了每个四面体的形状和尺寸,并建立了四面体环形结构与相应三向对称六连杆机构的关系.然后以结构在任一展开状态时旋转铰轴线倾斜方向为广义位移,得到旋转变量的输人输出关系方程,证明了结构的运动具有单自由度.
Based on Kaleidocycles and threefold-symmetric Bricard linkages, a new type of retractable structure was developed. This structure took threefold-symmetric Bricard linkages, composed of six tetrahedrons, as fundament, and implemented retractability through tetrahedrons' rotation around the adjacent hinges. The form and design principle of this structure was presented. On the basis of the geometric parameters of this structure, the shape and dimension of every tetrahedron were determined, and then the relationship between rings of tetrahedron and the corresponding threefold-symmetric Bricard linkages was established. Furthermore, taking the inclining direction of the rotating axes as general displacements, the input-output equation of the rotating variables was obtained, which demonstrated that the movement of this structure had one freedom degree.