sentences:  Sheet metal feature recognition library extracts features from a sheet metal perspective.Various features identified through this library include walls, bends, holes, cutouts, flanged holes, flanged cutouts, notches, open hems, closed hems, teardrop hems, rolled hems (curls), jog flanges, edge flanges, contour flanges, stamps such as louver, lance, bridge, dimple, beads, embosses and ribs.Though such commercial systems can identify a variety of features listed above, further research can be driven to identify feature types that are not identified by such commercial systems.