An approach to identify and select optimal temperature-sensitive measuring points for thermal error compensation modeling in CNC machines: A case study using cantilever beam

Abstract

In the Present machine tool industry, CNC machine tools are capable of meeting the demands like high productivity, high precision and reliability. But, accuracy of the machine tools is greatly affected by three types of errors, 1) geometric error, 2) thermal error and 3) cutting force induced error. Among these errors thermal error contributes more than 70% of total error. Thermal error management on machine tool is done through two approaches; they are 1) Thermal error reduction approach and 2) Thermal error compensation approach. This work deals with only thermal error compensation approach. Identification of thermal sensitive region on machine tool is the most challenging task of thermal error compensation. Thermal imaging is an experimental method which is currently being used to identify thermal sensitive region on machine tool. But this method is associated with more time, human efforts and high cost. Hence, in this work, two numerical methods such as thermal error sensitive method and thermal modal analysis method were used identify the thermal sensitive region. Here, cantilever beam was considered as a case study to illustrate the selection of thermal sensitive points.