Tool geometry and motion design in CNC machining with offset control

Abstract

Abstract CNC machining is the main subtractive manufacturing technique. Although it has been used for decades, it is far from perfect and still causes many problems due to complex geometric calculations. Our goal is to achieve high surface quality and to reduce the need for time-consuming finishing processes such as grinding and polishing. Our research is based on a complete geometrical analysis of the machining process and the identification of the curve by a linear-quadratic contact between the tool and the target surface. From a geometrical point of view, we succeeded in establishing a new smooth transition between the results of classical surface coverage theory and the oscillating rings on curved surfaces and the "double" oscillating rings on tangential surfaces. Unlike previous machining methods for curve matching, curve matching on curved surfaces is achieved by solving locally optimal tool position and motion planning by a single optimization.