Robot Assisted Machining of Thin-Walled Structures

Abstract

This paper proposes and studies the use of industrial robot manipulators to act as an active steady rest in machining thin-walled workpieces to prevent machining chatter instability. Feedback control is applied to the robotic steady rest in contrast to the other more popular active control method where the cutting tool is controlled. The entire dynamic system model is characterized by delay differential equations with time varying interactions between the tool side and work side dynamics. Semi-discretization, finite element modeling, and model reduction are applied to obtain a lower order plant model for the feedback control design. Control design and simulation results on turning of thin-walled tubes are presented to demonstrate the effectiveness of the proposed modeling and control approach for the robotic active steady rest.