Feature attraction

The increasE in CAM programming tools incorporating automatic feature recognition may well signal a shift in the route to increased productivity.

There is only so much that can be achieved using increased spindle speeds/feeds, pallet shuttles and 5-axis machining cells as manual programming ties up resources and holds up workflow.

Automatic feature recognition — the pinnacle of 25 years' research — has been arrived at through steady developments in 'knowledge-based machining' technology.

Feature recognition really started when traditional 'process-based' CAM systems began to reduce the number of individual manual-based operations needed to generate a toolpath by grouping operations, such as defining boundaries in standard processes. These processes could be remembered by the system and repeated in future operations, making it easier to program similar toolpaths next time round.

The vast majority of CAM developers exploring the possibilities of automatic CAM have based their developments on a system first proposed by Lyc Kyprianou at Cambridge University in 1980. Kyprianou devised a system to algorithmically extract higher level entities such as manufacturing features from lower level elements, such as surfaces and edges, of a CAD model. When he first proposed the method it aimed to encode parts for group technology (GT).