Development of the piezoelectric dynamometer for brittle material drilling

When processing deep and small holes in optical glass with a diamond core drill, the cutting force is minimal and very variable. It is challenging to measure the cutting force because of the high cutting frequency and small value of the cutting operation. In this study, a piezoelectric three-component dynamometer with excellent axial sensitivity is developed based on the measuring properties of quartz wafers and characteristics of cutting forces during processing. The dynamometer's four sensors are positioned vertically, which could increase the dynamometer's axial sensitivity. The dynamometer's calibration studies were conducted in both static and dynamic modes. The output consists of the dynamometer was verified using a multi-point loading experiment. According to the experimental findings, the dynamometer's linearity error and repeatability error are both less than 0.5%. Less than 1.6% and 2.9%, respectively, are found in the output error and crosstalk of multi-point loading experiment. The frequency of nature is higher than 1500 Hz. An experiment measuring cutting force was completed lastly. The findings of the experiment confirm the viability of the dynamometer by demonstrating that it performs well and can identify changes in cutting force caused by two distinct cutting tools when operating under various conditions.