针对含冗余约束和被动自由度的闭环机构,解决其关联杆组中基本连杆的排列组合问题。采用Matlab程序,求解关联杆组中基本连杆的数目,确定基本连杆的组合形式。该方法与决策树方法相比,避免了数据的遗漏。同一关联杆组中基本连杆排列方式同构,推导出的拓扑胚图同构。提出选择性插入方法解决基本连杆的同构排列问题,通过程序实现,证明该方法能减少运算量,节省运算时间。举实例说明程序自动生成有效基本连杆排列方式的应用过程。结果表明,所提出的运算方法能在进行闭环机构拓扑胚图综合之前,清除同构的基本连杆排列方式,保证后续推导的拓扑胚图的有效性,同时便于在计算机上实现,提高自动化程度。
Aiming at closed mechanisms with redundant constraint and passive degree of freedom, the problem of basic links permutation and combination of their associated linkages is solved. The number of basic links is solved and the arrangement form of basic links is determined using Matlab. This method avoids the missing data compared with the method of decision tree. For the same associated linkage, topology embryonic graphs are isomorphic if their arrangements of basic links are isomorphic. Selective insertion method is proposed to solve the problem of isomophic arrangement of basic links. It proves that this method can reduce the amount of computation to save computing time by Matlab program. Examples are given to illustrate auto-generation of the effective arrangement of basic links procedure and specific application. The results show that the proposed method can effectively remove isomorphic arrangement of basic links before the integration of topology embryonic graph, which ensure the effectiveness of the subsequent topology embryonic graph derived and also allow the computer to achieve.
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