Identification of A Novel Kinematic Model of Articulated Arm Coordinate Measuring Machines with Angular Positioning Deviation “Error Map” of Rotary Axes   Ryuichi Saito, Soichi Ibaraki       Abstract   Articulated Arm Coordinate Measuring Machines (AACMM) have been increasingly used in the manufacturing industry in recent years because of its portability and flexibility in measurement. However, the measurement accuracy of AACMMs is often significantly worse than conventional CMMs. To improve the measurement accuracy of AACMM, the modelbased compensation has been studied. The Denavit–Hartenberg (D-H) model, which is widely used in robotics field, only contains position and orientation errors of the rotary axis average lines. In this study, we propose a new kinematic model of AACMM with the angular positioning deviation “error map” of rotary axes. The angular positioning deviation is modelled as a function of the rotary axis angular position. A method to identify the angular positioning deviation of rotary axes is also proposed by constraining the stylus position at various locations over the workspace. A machine tool, with a magnetic sphere socket installed on its spindle, is used to position the stylus sphere at the prescribed locations.   Keywords: Articulated Arm Coordinate Measuring Machines, Kinematic Calibration, Measurement Accuracy, Error correction         >> Back to Home