This study aims to calibrate the posture of a robot-type machine tool comprising parallel and serial links using a kinematics error model and verify the machining performance based on the measurement results of a machined workpiece calibrated with kinematics parameters. A robot-type machine tool (XMINI, Exechon Enterprises LLC) is used in this study. Typically, the performance required of a robot-type machine tool is not only dimensional accuracy but also the contour accuracy of the machined workpiece. Therefore, in this study, we first construct a forward kinematics model of a robot-type machine tool and identify the kinematics parameters used in it via spatial positioning experiments using a coordinate measuring machine. Based on the parameter identification results, we calibrate this robot-type machine tool and evaluate its machining performance in terms of the dimensional accuracy and contour accuracy of the machined workpiece.

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