Tool deflection is a major cause for shape deviations in milling. Therefore, an approach is presented to compensate tool deflection based on the drive signals of a milling center. First, a real-time capable model is implemented to reconstruct static process forces by using the drive signals of a machine tool. To calculate the actual deflection, the forces are combined with a stiffness model of the tool. Finally, a controller is designed to minimize shape deviation of the workpiece. Based on experimental milling investigations it is shown that tool deflection can be significantly reduced.
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