The sensor fusion method using both art acoustic emission (AE) sensor and a
built-in force sensor is introduced for online tool condition monitoring d
uring turning. The cutting force was measured by a built-in piezoelectric f
orce sensor which was inserted in the tool turret housing of an NC lathe. F
EM analysis was carried out to locate the most sensitive position for the s
ensor. A burst of AE signal was used as a triggering signal to inspect the
cutting force. A significant dr-op in cutting force indicated tool breakage
. The algorithm was implemented in a DSP board and the monitoring system wa
s installed on a CNC lathe in an FMS line for in-process tool-breakage dete
ction. The proposed system showed an excellent monitoring capability.