Abstract: In order to faciliate the integration of a CAD / CAM system,the feature definition and infonnation construction are analysed and expressed by hierarehical structure.The feature face is a constructive unit for forining feature,and the feature relationship is established using feature attached face。During parametric modeling,the feature shape and locating can be modified by dimension driving,and the relationship between features is described by local coordinate frame. As necessary implementation,feature information is organised through objectoriented techniques, which is also discussed finally.

Key words: computer aided manufacturing, systems integration, parameterization, design