提出一种可满足给定几何坐标的张拉整体结构找形方法.从结构平衡方程的2种不同形式出发,借助平衡矩阵奇异值分解与力密度矩阵特征值分解后得到的正交向量,分别构造自应力及几何坐标,并引入节点坐标作为约束条件,给出基于构件自应力与节点坐标非线性迭代的求解技术及其算法流程.结果表明,只需给出结构拓扑连接关系及若干已知节点坐标,找形算法便可用于寻找满足给定几何外形的张拉整体以及新的非规则张拉整体形式.
A new form-finding method for computing the given nodal coordinates tensegrity was proposed. The equilibrium equation was formulated in two different ways. Based on the orthogonal vectors that were generated by the singular value decomposition of equilibrium matrix and eigenvalue decomposition of force density matrix, the self stress modes and nodal coordinates were obtained, respectively. The given nodal coordinates were introduced as constraint conditions. Self stress modes and nodal coordinates were calculated iteratively until the results converge, and the corresponding procedure was established. The topology and a set of nodal coordinates were specified in this method. The proposed approach can be applied to the form-finding of tensegrity with required shape, and the form-finding of novel nonregular tensegrity system.