Piezoelectric active control for workpiece chatter reduction during milling

Abstract

Regenerative chatter is a form of unstable, self-excited vibration that occurs in machining operations such as milling and turning. In high speed milling of many aircraft components, regenerative chatter is the fundamental factor that limits metal removal rate and consequently productivity. Regenerative chatter is essentially a feedback process: the cutting chip thickness produces a force between the tool and workpiece, and the dynamics of these components results in a change in the cutting chip thickness. An exciting method of avoiding chatter is to actively control the workpiece or tool during cutting. On thin walled workpieces, such as those for aerospace structural components, this can be achieved using piezoelectric devices. A wide range of control regimes could be applicable, such as feed-forward actuation, active constrained layer damping, or active damping, using either non-collocated or collocated sensors and actuators. This study focuses on active damping with collocated sensors and actuators. In this article, an experimental study is described whereby workpiece chatter during milling is reduced by using active vibration control with piezoelectric sensors and actuators.