Stability and Nonlinear Dynamics of Variable Speed Milling

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

Chatter, the self-excited relative vibration between workpiece and cutting tool, is a common problem in the machining process. Its adverse effects include noise, poor surface finish, reduced dimensional accuracy, and shortened machine tool life. The onset of chatter limits material-removal rates and productivity. The purpose of this project is to clarify the mechanism of suppression of chatter through continuous modulation of spindle speed. The project addresses this issue using a combination of analytical, numerical, and experimental efforts, bridging the gap from the one-degree-of-freedom turning model to realistic models for high-speed milling processes. The unifying theme in the work is a study of the nonlinear delay differential equations that govern the tool motion. It is planned to transfer to industry innovative theory and simulations developed in the project, allowing improved design and greater performance of various material removal processes. The project will develop web-based simulators to be used in senior undergraduate and graduate courses and to provide industrial designers with a predictive tool to avoid unwanted machine behavior. These graphical tools will enhance understanding of the effect of noise and fluctuating time delay on real engineering problems. The project provides an excellent environment for student education through research at the interface of applied mathematics and engineering.