Force Sensors Suitability Evaluation for Strong Gripping Force Beyond 50 kN

This article evaluates the suitability of force-sensing mechanisms for measuring strong gripping forces beyond 50 kN in computer numerical control (CNC) lathe machines. Using finite element analysis (FEA), the effects of gripping force on chuck jaws were examined, revealing significant stress and deformation, particularly on the front surface. Based on this analysis, strain gauge load cells and piezoresistive sensors were selected for further evaluation. Experimental results showed that while both sensors could measure high forces, strain gauge load cells outperformed piezoresistive sensors, maintaining accuracy and reliability even under high mechanical stress. A sensor-integrated jaw system was developed, providing real-time force measurements under machining conditions. Future work aims to incorporate a real-time motor torque control system based on sensor feedback, enhancing the safety and precision of CNC operations by preventing insufficient gripping forces and workpiece damage.