为了克服传统刚体导引机构综合方法的缺陷，如结构类型限制和功能特性不定性，提出了基于功能模块相似变换的广义综合方法． 以带轮机构为研究对象，首先建立运
动学分析模型，提取导引输出运动特征参数，建立了全拓扑信息的带轮机构功能模块． 然后通过分析机构尺寸与导引转角函数和轨迹的内在关联，揭示了机构功能特性与尺寸参数的映射规律，给出合理预选功能模块尺寸参数的方法． 最后引入了模糊导引运动设计，通过中心射影相似变换实现功能模块的几何定位求解，确定了机构的实际尺寸和安装参数． 综合算例验证了该综合方法的有效性和实用性．

In order to overcome the defects of the traditional synthesis methods for rigid-body guidance mecha- nisms,such as the limitation of mechanism structure types and the uncertainty of functions,a generalized synthesis method based on the similarity transformation of mechanism function modules is proposed.In the method,first,by taking a belt mechanism as the objective,a kinematic analysis model is constructed and the output motion charac- teristic parameters are extracted.Next,the corresponding function module with full topology information is built.Then,by analyzing the intrinsic relationship between the mechanism parameters and the coupler rotation-angle function as well as that between the mechanism parameters and the guidance trajectory,the mapping rules between the guidance functions and the dimension parameters are revealed,and a method to preselect the reasonable dimen- sions of function modules is put forward.Finally,a fuzzy guidance motion design is introduced,and the geometric positioning of the mechanism function modules is accomplished through the center projective similarity transforma- tion,thus obtaining the actual dimensions and installation parameters of the mechanism.By a numerical example,it is proved that the proposed method is effective and applicable.