Design and analysis of a strain gauge based eight-shaped elliptical ring dynamometer for milling force measurement

This study describes the design, analysis, and development of a strain gauge-based dynamometer for measuring the cutting force during the milling process. The objective is to increase the deformation of the ring with an applied load so that it can be measured more easily. Based on the analysis and test results, the eight-shaped (ES) rings with an elliptical hole were finalized. It was shown that the ring has a higher deformation of 0.02822 mm for a normal load and 0.2136 mm for a tangential load. Also, the induced von Mises stress is 39.63 MPa for axial and 194.8 MPa for tangential load, each of which is less than half of the yield strength. Hence, for the finalized design the metallic ring was fabricated, and sensors were bonded. Then, the calibration and metrological characterization was performed. Overall, the designed dynamometer is found as suitable for measuring the cutting force in the milling process.