Intelligent Recognition of End Milling Conditions Based on Cutting Force Model (Development of Monitoring Method without Any Databases)

Abstract

An intelligent method is proposed to recognize various end milling conditions by comparing simulated and measured cutting forces. Static stiffness of the mechanical structure is identified by utilizing the measured cutting forces, and it is shown that the static deformation of the structure can be taken into account for accurate calculation of uncut chip thickness in the end milling process. A cutting force equation is developed with considering cutting edge roundness, i.e. tool wear, and a milling force model is constructed. Various parameters in the model are identified so that the simulated forces fit best with the measured forces. Edge force component, tool setting angle, specific cutting force resistance, etc. are identified or recognized as the model parameters, which contain rich information about the end milling process. End milling experiments are carried out at various stages of tool wear, and the results show that the proposed index for the tool wear, i.e. the identified edge force component divided by the specific cutting force resistance, has good correlation with the measured tool wear. It is expected that the end milling conditions such as the tool wear, the static stiffness of the structure, the tool setting angle and the specific cutting force resistance can be recognized intelligently without any data bases by the present method.