构造一种含环路布局、构件类型、运动副类型和运动副轴线方位信息的运动链的拓扑特征矩阵。构件的类型构成特定的环路布局,运动副的类型及其轴线的方位配置决定运动的状态特征,多副构件是联系环路间的桥梁。以运动链构成的独立环路为基础构建特征矩阵的行数,运动链的构件数目构建特征矩阵的列数;以独立环路的旋向确定构件及其排序;以代表运动副类型的符号或数字表达构件及环路间的连接关系;以同一构件上两个运动副的相对轴线方位描述运动副的方位特征。构造的运动链特征矩阵为(2l+2)×n,而单环运动链为3×n矩阵。实例表明,该特征矩阵可以描述各类运动链,与传统n×n拓扑矩阵相比,结构大大简化,而且拓扑信息量多。该矩阵特别便于由特征矩阵构造对应的机构简图,同时也为计算机辅助运动学和动力学建模提供了一种便捷途径。
A topological characteristics matrix with information of loops, types of links and joints, and orientations of joints is proposed. Loops are formed according to the kinds of links (binary or multi-joint link), and the moving space of the kinematic chains are determined on the basis of types of joints and their orientations. The multi-joint links set up the connecting among loops. The rows of the matrix are designed based on the independent loops, and the columns on the numbers of links n, the links dements in the matrix are ordered according to the direction of independent loops, the joints are expressed by prescribing letter or number, the orientation of joint is defined as the axes between two pairs of same link. The topological characteristic matrix is (21+2)×n, and it is 3×n matrix for single loop kinematic chains. Examples show that all kinds of kinematic chains can be presented by the matrix. The matrix provides more topological information of kinematic chains with fewer elements. The matrix makes it easier to construct the corresponding structural sketch from the matrix elements, and it also provides an easy way for computer-aided kinematic and dynamic modeling.