Abstract: Fragmentation method is applied to create model of complicated parametric surface and in consequence，surface feature is analyzed.On the basis of the geometrically universal characteristic of torus end-mill tool，the precision error of the track is analyzed and the tool path generation algorithm on occasion of iso-scallop is given.Then the fair of the pieces is processed.According to this algorithm，tool-pose changes along with the curvature of machining surface，which leads to the improvement of machining quality as well as the prevention of interference between workpiece and tool.

Key words: fragmentary modeling, torus end-mill, surface feature, tool pose, tool path

摘要： 采用曲面分片思想建立复杂参数曲面模型并进行了曲面特征分析。在曲面片域内基于环形铣刀几何特征的一般性，进行了精度误差分析，建立了等波高刀具路径规划策略，使刀具姿态随工件曲面的曲率而变化，并完成曲面片间的光顺整合。基于该分片算法，可有效改善复杂曲面的加工质量并能积极预防刀具与工件的干涉。

关键词: 分片建模, 环形刀, 曲面特征, 刀具姿态, 刀具路径