Flat-end tool orientation based on rotation-minimizing frame

Abstract

Well-designed tool orientation is crucial for the quality execution of five-axis machining with flat-end tools. Tool orientation can be specified in terms of tool inclination and tool tilt angles. For a given surface path, these aspects need to be specified for each cutter contact point along the path, because poor tool orientation choice can cause large axial acceleration of the machine tool, leading to inferior quality of the machined surface. The rotation-minimizing frame aims to reduce unnecessary frame rotation during movement. This concept has been adopted to develop tool orientation methods that allow variation in the inclination angle, the tilt angle, and both the inclination and tilt angles. The intention is to reduce unnecessary rotation of the tool frame as the tool follows a specified path. Evaluation was conducted in the context of five-axis flat-end tool machining. Based on these methods, tool orientation was planned along surface paths of a torus, sphere, and dome. Changes in tool orientation were always smooth. From the perspective of reducing tool orientation changes and axial acceleration, it was demonstrated that simultaneous variation of the inclination and tilt angles based on rotation minimization provided the best results.

Keywords

Five-axis machining / Tool orientation / Rotation-minimizing frame / Numerical control

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