Smart Cutting Tool Integrated With Optical Fiber Sensors for Cutting Force Measurement in Turning

Real-time cutting force measurement is significantly important to monitor tool condition and machining process. Although commercial dynamometers are available for a range of machining applications, there is a lack of multipoint and low-cost measuring methods suitable for detecting cutting forces in harsh machining environments. In this paper, a smart cutting tool integrated with optical fiber sensors is first presented for cutting force measurements in turning. Fiber Bragg grating (FBG) sensors are employed to acquire cutting force information on cutting tools. Compared with the electrical and piezoelectric sensors, the proposed smart cutting tool has unique advantages such as electromagnetic interference immunity, explosion proof, ability to measure multiple cutting forces in the same and simplified data acquisition device with along-distance signal transmission, and enabling it to work in harsh machining environments. In addition, the proposed smart tool brings little effect on the structure and characteristics of machine tools due to FBGs' small size and light weight. This paper investigates the operating principle of the sensory cutting tool theoretically and validates it using finite-element simulations. A prototype of the proposed device was developed and tested. Static calibration, dynamic identification experiment, and comparative cutting tests were conducted to evaluate its performances. The experimental results have shown that the cutting forces acquired by the developed smart tool are in good agreements with the results obtained by the reference commercial dynamometer. The proposed smart cutting tool has the potential to provide a new solution to the real-time measurement and monitoring of multipoint cutting forces in turning processes.