Reconstruction of propeller deformation based on FBG sensor network

Abstract

Real-time prediction of the deformed propeller has important implications in engineering applications. While, the traditional contact measurement method cannot satisfy the on-line measurement of propeller deformation, because the weight and arrangement of the strain gage used will make it difficult to measure propeller deformation. In this paper, the FBG sensing technology was applied to detect propeller deformation, which was constructed based on discrete input strain measures in the structure. To avoid the inaccuracy and complexity of contact measurement of propeller deformation, this paper proposed a strain-deformation reconstruction method (inverse finite element method based), where a linear discretization-inverse finite element deformation reconstruction algorithm was developed based on the unique shape and structure of the propeller at the same time. In this paper, a propeller strain-deformation reconstruction experimental system based on the FBG sensor network is constructed, according to which a single propeller blade is loaded and the deformation is reconstructed. Meanwhile, the deformation of the blade is measured with a Hexagon Three-Coordinate Measuring Arm. From the study, the error between the reconstructed deformation and the measured deformation propeller is within 7% under the concentrated load of 50N, 100N and 150N, which clearly verifies the feasibility and accuracy of the strain-deformation reconstruction of the propeller.