Improving free form surface machining performance by ball end milling model

Abstract

In CNC (computer numerical control) programs, cutting tool needs to move along a path described by a sequence of curves starting from the predefined Cutter Location (CL) points. In this article, cycle time is minimised and cutting forces are limited by a threshold for toolpath generation. In order to determine the cutting forces in each direction for all CL points a force map which overlapping with a uniform Cartesian mesh is constructed showing all possible cutting forces from each CL point to its neighbours. This map is obtained by pre-computation of force simulations in each direction. Force simulation of the newly developed paths and its experimental validation are obtained and compared. Moreover, forced-based feedrate scheduling strategy is utilised for the same free form surface to decrease cycle time. Feedrate is adjusted along toolpath to keep cutting forces at preset force value.