Force Prediction Model for Five-axis Flat End Milling of Sculptured Surface

Abstract

Milling force is an important basis for optimizing process parameters, designing machine tools, cutters and fixtures. An analytical algorithm of in-cut cutting edge based on space constraint method is proposed for five-axis flat end milling of sculptured surface, and the prediction model of milling force is established considering cutter runout. Based on the idea of differential discretization, the sculptured surface can be assumed as a series of tiny inclined plane. The arbitrary relation between cutter geometry, feed direction and workpiece is defined by parameterization taking the five-axis flat end milling of inclined plane as the object of study. The conditions of cutting edge element involved in cutting are proposed, and the entire in-cut cutting edge is obtained by searching along the edge curve. Combined with the classical micro-unit milling force model, force prediction model for five-axis flat end milling of inclined plane can be established, then the force prediction for five-axis flat end milling of sculptured surface can be realized. Moreover, the transition matrix of milling force from cutter coordinate system to workpiece coordinate system can be derived. The simulation results show that the spatial constraint method is simpler and more versatile than the cutter workpiece engagement limitation method. The experiment results show that the predicted force is in good agreement with measured force in both trend and amplitude, which proves the validity of the milling force prediction model.