Indirect Measurement of the Cutting Power Based on Spindle Motor Current

Enhancing energy efficiency of machine tools can significantly improve the environmental performance of machining systems, and acquisition of cutting power is the key to solve this problem. However, the approach that the cutting power is directly measured by the dynamometer can’t be utilized in real life application. In this paper, a cutting power estimation model, based on the inexpensive and non-invasive spindle motor total current and spindle idle current measurement, is proposed for the intermittent cylindrical turning operation. Novel signal processing strategies have been proposed for extracting useful features from the measured signals. Some experiments are performed on a CNC lathe HCK60 for the identification of the load meter constant and the analysis of the estimate error. As a result, it shows the effectiveness of the proposed method for estimation of cutting power, which can enhance the overall productivity of the machining process by optimally selected cutting parameters from the predicted model.