Volumetric error analysis and modelling of CNC internal and external cylindrical grinding machine tool

In order to improve grinding accuracy, it is necessary to analyze and study geometric and thermal errors of NC machine tools. Based on the method of coordinate transformation of multi-body system theory, the error matrix of cutting points is established in workpiece and tool kinematic chains. The coupling relationship between thermal error and geometric error is analyzed, and the comprehensive mathematical model of geometric error and thermal error of CNC internal and external grinder is deduced. The precise machining constraint equation of grinder is established, which lays a theoretical foundation for subsequent error compensation.