Cutting Deflection Control of Thin-walled Part Based on Real-time Force Signal Detection and Processing

Machining accuracy of thin-walled parts which have low-rigidity is greatly influenced by cutting deflection in flank milling. In this paper, workpiece deflection during machining is controlled based on real-time cutting force signal processing and control strategy of on-line feedrate optimization. The model of workpiece deflection is established to obtain the numerical relationship among cutting force, feedrate, and deflection, which is usually used to get optimized cutting force by setting the allowable value of workpiece deflection. To implement on-line deflection control, a real-time control strategy of feedrate optimization based on nonlinear root-finding algorithm of Brent-Dekker and corresponding optimization principles is developed and integrated into open modular architecture CNC system which has the function of real-time force signal sampling and processing. Experimental results show that workpiece deflection is effectively controlled by the proposed strategies.