Date of Award


Document Type

Thesis (Ph.D.)


Department of Computer Science

First Advisor

Scot Drysdale


Current automated machining systems are composed of a number of components to aid in bringing a surface from design to physical completion. Numerically controlled (NC) milling machines are used to cut parts out of stock. Programming these machines to cut a desired surface is still largely a matter of experienced human participation. Therefore, the need exists to verify that tool programs produce the desired part.

We present recent developments in the verification of NC tool programs. Many of these methods rely on approximating the stock material as vectors whose lengths reflect the amount of uncut material at any point. This allows simulation of 3-axis machining to be carried out efficiently, because the intersection process is simple to compute. Some machines are capable of 5-axis tool movements which are more versatile, but verification of these programs is difficult due to the complexity of the tool motion.

We show several techniques by which it is possible to determine the intersection of 5-axis tool movements and guarantee the accuracy of the results. These techniques can be integrated into current NC machining verification systems to allow checking of 5-axis programs. We then evaluate the relative performance of implementations on test data and real world data.


Originally posted in the Dartmouth College Computer Science Technical Report Series, number PCS-TR93-191.