Real-time monitoring of tool fracture in turning using sensor fusion

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.