On-Line Monitoring of the Dimensional Error in Turning of a Slender Shaft

Abstract

Bending deformation is easy to occur when turning a long slender workpiece due to its low stiffness, which seriously affects the machining dimensional accuracy. Currently, the dimension of the part is generally measured off-line after the completion of the operation. The purpose of this paper is to explore an on-line monitoring method for the dimensional error of slender shaft in turning processes. First the deformation of the whole workpiece in the process of machining is analyzed. The deformation correlation at the measuring point and that at the cutting point is deduced. Then an on-line monitoring approach to radial dimension is proposed using a single fixed displacement sensor and Wavelet Transform. Finally, the reliability of the monitoring method is verified by machining experiments. The experimental results show that the presented on-line monitoring model enables to predict the dimensional error of the machined workpiece effectively.