Abstract: A multi-roller and multi-sensor measurement solution based on the analysis on the intrinsic limitations of the single-roller method is proposed to measure the large diameters accurately.In the measurement system designed, the multiple rollers and data fusion technology are used to eliminate the sliding signals, as well as the separating and correcting the measurement errors aroused by the thermal-deformation and pressure deformation to improve the measurement accuracy of the system observably.In this paper, the measurement principle and system of the roller method are introduced and the measurement errors are analyzed.The experimental results show that the measurement accuracy of designed system exceeds 5 μm/m.

Key words: multi-roller method, large diameter, data fusion, error separating and correcting