9301115 Jerard This research increases the current knowledge base in the field of numerically controlled (NC) machining of sculptured surfaces. This knowledge is important for any industry using five- axis NC sculptured surface machining. Two industrial collaborators are included in the project. Previous research has developed fast and robust algorithms for simulation and verification of sculptured surface NC machining programs. The simulation method uses a technique for discretization of parametrically defined surfaces into a Surface Point Set (SPS). The simulation method has been used as a basis for generation and automatic correction of three axis NC programs. This research is focused on methods for five axis tool positioning and geometric modeling of five axis path swept envelopes. This research specifically explores the following questions: (1) What are the best algorithms for subdivision of sculptured surfaces into a discrete representation to be used for NC tool path generation? (2) What is the time/accuracy trade-off in using points versus polygons as a surface representation for NC tool path generation? (3) Can our non-isoparametric tool path planning algorithm developed for three axis machining be extended to the five axis case?