Piezoelectric sensors and actuators for milling tool stability lobes

In this article, the authors describe the use of piezoelectric sensors and actuators for the prediction of milling tool stability lobes, since existing methods for predicting tool stability have disadvantages which limit their practical use. An experimental approach is described whereby modal testing is performed using surface-mounted piezoelectric sensors and actuators to generate a prediction of tool instability due to regenerative chatter. The approach is first demonstrated by synthetic modal analysis based upon a finite element model of a cantilever beam. Laboratory tests are then performed on small milling tools, and it is shown that there is good agreement with alternative methods for predicting stability. It is concluded that the proposed technique may be more readily suited to automation, and is more appropriate for use on very small milling tools.