Abstract
NC commands are generated by CAM systems to realize high speed and high accuracy machining. At the time, the feed rate in most of NC data may be set to be constant in machining any workpiece shapes. In addition, NC data do not necessarily reflect the workpiece shape correctly due to the variation in the coordinate point values calculated by CAM systems. It causes the reduction in the machined surface quality. The shape recognition in the tool feed direction on the basis of NC data has already been devised. Thus, the study enables 3-D shape recognition to be identified from NC data in the pick feed direction as well as those in the feed direction. After the identification, the feed rate can be controlled according to the identified shape information. The system developed in the study can detect the distinguishing points from the coordinate information in NC data. Then, the points are arranged to generate the smooth tool motion and to control the feed rate for the identified workpiece shape. From experimental result, it is confirmed that the machined surface quality is successfully improved and the machining time is also reduced.
