A machining test to evaluate thermal influence on the kinematics of a five-axis machine tool

Abstract

The thermal deformation of a machine tool, typically caused by environmental temperature variations or the heat generated by a rotating spindle, often changes the position and orientation errors of the rotary axis average lines. By applying kinematic modeling of a five-axis machine tool, this paper shows that they can be estimated from the finished geometry of any test piece, provided that the test piece contains the features that are sufficiently sensitive to them. Based on the kinematic analysis of their influence, a new machining test is proposed to evaluate the thermal influence on the position and orientation errors of the rotary axis average lines. By inversely solving the five-axis kinematic model, this paper shows that the position and orientation errors of the rotary axis average lines can be analytically identified by the finished test piece geometry. An experimental case study demonstrates that the position and orientation errors of the rotary axis average lines, which change due to the thermal influence, can be observed from the finished test piece geometry.