Machining, Measurement, and Control Laboratory

Monitoring and Adaptive Control of Cutting Forces Based on Spindle Motor and Servo Motor Currents in Machining Centers
Hidenori Saraie (Mori Seiki Co., Ltd.)
Masahiro Sakahira (Kyoto University)
S. Ibaraki (Kyoto University)
A. Matsubara (Kyoto University)
Y. Kakino (Kyoto University)
Makoto Fujishima (Mori Seiki Co., Ltd.)

For the intelligent manufacturing by a machining center, the authors have proposed an extension of fixed cycles to end milling processes in our previous works. For the enhancement of machining productivity, the extension of tool life, and the improvement of machining accuracies, we have proposed a scheme to optimize machining parameters within such a fixed cycle based on the regulation of cutting forces by using the initial machining database. In continuous machining, cutting forces gradually increase as the tool wear progresses. Therefore, it is crucial to perform a more reliable process control by continuously monitoring the cutting force. It is, however, unfavorable to install an additional sensor to monitor cutting forces from the viewpoint of the cost, reliability, and maintainability. To address this issue, this paper presents a scheme to estimate cut-ting forces by monitoring spindle and servo motor currents, along with a kinematic parameter defined by the geometrical interference between a tool and a workpiece.

Key words: End milling, Fixed Cycles, Cutting Force Control, Tool Wear, Monitoring of Cutting Forces, Adaptive Control.