中文摘要：

为提高工件加工的质量,研究面向精加工工序的夹具定位方案自动规划方法,根据工序要求和工件几何特性建立定位基准的选择和评价准则。将工件的加工工序要求转换成设计基准的约束自由度任务,根据几何特性建立基准约束能力评价方法,利用基准的几何类型和位置关系类型评价基准的约束自由度能力。根据基准之间的位置关系建立基准的组合和基准替换方法,解决基准定位能力不足和基准约束冲突问题,在定位能力评价和定位问题解决过程中确定基准的定位点数量和布局。利用UG NX 7.5开发平台和VC＋＋语言,编制基于三维实体模型的夹具定位方案自动规划原型软件,并通过实例进行了验证。

英文摘要：

To improve the quality of workpiece machining,the automated planning approach for fixture location oriented to finishing process was studied.According to th eprocess requirements and the workpiece geometrical features,the evaluation criterion of location datum was determined.Process requirements of workpiece was converted to the constrained Degrees Of Freedom（DOF）of design datum,the evaluation method of datum constraint ability was established,and the capability of constraint DOF of workpiece datum was evaluated according to the geometrical types and the types of position relationship.The combination and the replacement method of datum were constructed based on position relationship between datum.Thus the datum conflicts and the incapability of the datum locating were solved.The location quantity and the layout of the datum locating points were determined during the process of the locating ability evaluation and the locating problem resolution.The automated location planning prototype software of fixture for 3Dsolid model was developed by UG NX7.5development platform and VC＋＋Language,and it was proved to be effective by examples.