Data-driven compensation method for on-machine measurement errors of freeform surfaces
摘要
The on-machine measurement (OMM) system is subject to various error sources, making it challenging to identify and compensate for them. Existing error compensation methods necessitate extensive calibration experiments and the development of complex error identification and compensation techniques, making it difficult to ensure measurement accuracy for complex structures like curved surfaces. Therefore, this paper proposes a measurement data-driven method for OMM error compensation. The method is designed for a specific surface with complex geometry, and firstly, probe error compensation is realized by the method of standard sphere calibration, which compensates the probe error to a certain extent. Then, the surface is measured by coordinate measuring machine (CMM) and OMM system respectively. The error identification and compensation of the measurement results of specific geometrical structures are realized by designing a convolutional neural network (CNN). Simulation and experimental results demonstrate that the proposed method effectively enhances the compensation of measurement errors for specific geometries.