Design and development of strain gauge based milling tool dynamometer

Measurement of cutting forces during machining has been done widely since it influences the cutting tool performance, machined surface characteristics, machine design and tool design. A three component strain gauge based milling tool dynamometer has been designed and manufactured. Octagonal rings were used as spring elements. Strain gauges were bonded on octagonal rings to sense the deformation. Wheatstone bridges were made between strain gauges to measure the change in resistance due to deformation of rings during metal cutting. Since the output of bridges was very small, it was amplified and converted into digital signals. Calibration was done for all directions. Milling operation was carried out to test the dynamometer. It was noted that the developed dynamometer is reliable and accurate during metal cutting.