Machining, Measurement, and Control Laboratory

A Long-term Control Scheme of Cutting Forces to Regulate Tool Life in End Milling Processes
Soichi Ibaraki, Takuya Shimizu

Numerous researches on cutting force control in end milling processes have been reported in the literature. There have been, however, very few practical applications actually employed in commercial products. The paper presents a simple, practically feasible and effective scheme to regulate the tool life through a long-term control of cutting force. Cutting force changes quickly occurring due to tool path geometry are suppressed using model-based feedrate scheduling. Cutting force is monitored only at tool path check points, set typically at intervals of several dozen meters. Since it does not require continuous full-time monitoring of cutting forces, a ``cheaper'' estimation scheme of cutting forces can be potentially employed. Feedback control focuses only on a long-term point-to-point regulation of cutting force, targeting tool life providing cutting for the given desired distance. The effectiveness of the present approach is experimentally investigated by an application example to contour-parallel cutting of hardened steel.