Thermally Caused Location Errors of Rotary Axes of 5-Axis Machine Tools
Michael Gebhardt*, Alexander Schneeberger*, Sascha Weikert**,
Wolfgang Knapp*, and Konrad Wegener*
*Institute of Machine Tools and Manufacturing (IWF), ETH Zurich, CLA G6, Tannenstrasse 3, 8092 Zurich, Switzerland
**Inspire, Transfer Institute for Mechatronic Systems and Manufacturing Technology, Zurich, Switzerland
This paper presents the results of detailed thermal analysis of a 5-axis machine tool with focus on the rotary axes. The rotary axes are characterized regarding their position and orientation errors as a function of the underlying thermal load, contributing significantly to the overall accuracy. A physical model is presented, which allows the simulation of the thermal behavior of the rotary axes based on the power input to the drives of the rotary axes and the heat conduction in a swiveling rotary table unit and convection into environment. This enables an external online-compensation of thermal errors. The compensation model is verified and validated.
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