High-precision multi-scale data fusion method for micro-nano CMM and white light interferometer

Evaluating precision machining quality of multi-scale surfaces requires micro-nano instruments combined measurement and point cloud data fusion. Addressing the challenges of registration and fusion difficulties for the micro-nano coordinate measuring machine (micro-nano CMM) and the white light interferometer (WLI) measurement data, a multi-scale data fusion method based on calibrator-aided registration and feature separation method is proposed. The designed triangular frustum calibrator provides reference points and unifies the coordinate systems. Then the WLI measurement point cloud data was separated to form and micro-morphology datasets. The CMM data reconstruction was referred to the form dataset of WLI, and obtained the fusion form dataset. Finally, mapped the micro-morphology dataset onto the fusion form dataset will get the fusion surface dataset. Experimental results show that the RMS and Mean error of the fusion results are less than 1 μm, and this method has higher registration accuracy and fusion quality than ICP and WLSDF methods. Furthermore, the proposed method preserves more detailed micro-morphology, and the data fusion strategy can be used for point cloud registration and data fusion of different micro-nano scale measuring instruments.