This paper introduced the freeform feature modeling in HUST-CAID,defined classification and parameters combining with the HUST-CAID system(computer aided industry design system developed by Harbin University of Science and Technology),creating a freeform feature by this classification and parameterization.

Numeric and curve parameters for freeform surface feature models

Then,on the basis of the framework,this paper researched a validity maintenance for the freeform feature with attachment,which could keep the validity of freeform feature with attachment.

Research on parameterization of freeform feature model

Research on tool path generating technique for free surface with STEP-NC;

An algorithm based on bicubic B-spline surface interpolation for free surface design;

Non-linear error in the NC machining of free surface and setting of the tool s step;

Method of efficient continuous plastic forming for freeform surface part;

Research on the interference areas determination algorithm of freeform surface in NC machining;

A new method for reconstruction of freeform surface;