Geometric and force errors compensation in a 3-axis CNC milling machine (original) (raw)
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1MSc Researcher, Mechanical Department, Faculty of Engineering-Helwan, Helwan University, Cairo, Egypt 2Professor, Mechanical Department, Faculty of Engineering-Helwan, Helwan University, Cairo, Egypt 3Associate Professor, Mechanical Department, Faculty of Engineering-Helwan, Helwan University, Cairo, Egypt 4Associate Professor, Electrical Power and Machines Department, Faculty of Engineering-Helwan, Helwan University, Cairo, Egypt ----------------------------------------------------------------------***--------------------------------------------------------------------Abstract This paper proposes a systematic checking and compensation for positioning errors of turning CNC machine tools which is low cost and demands little time. The study aims to identify axes errors without the need to in-process sensing or laser measurements such as ball-bar or laser interferometer systems, the estimation of positional errors is based on an assessment of the target turning CNC Machine tool by che...
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The three-axis machine tools produce an inaccuracy at the tool tip which is caused by kinematics parameter deviation resulting mainly from manufacturing error and assembly error. Here, all linear axes are theoretically perpendicular (dot product, cos 90 o = 0) to each other and directed along the X, Y, Z coordinate, but in working machines, the axes are nearly perpendicular (cos 89.9 o 0) because of the reasons mentioned above. This kind of error can be taken into consideration only by the precise description of the actual kinematics of the machine tool. This paper attempts to develop a generalized error model for the effects of positioning errors of the components of the kinematic chain of a machine in the work space and the results obtained by this model have been verified experimentally. The mathematical model of the volumetric error, based on positioning error component, has been derived and the effect of error component on the volumetric accuracy at the cutting point has been...
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