Bending Deflection Estimation of the Beam-like Structure Based on Strain Measurements from a Fiber Bragg Grating Sensing Network

The beam-like structures are widely employed in civil, machinery, and aerospace engineering. However, the beam-like structure often suffers from undesired vibration problems due to the environmental incentives, which may influence the overall structural safety. Therefore, a real-time deformation monitoring system is critical to guarantee the safety of the beam-like structure under the condition of operating. This paper presents a novel deflection monitoring system that can be installed easily to any large-scale beam-like structures. The proposed system contains a sensing network, which is constructed of fiber Bragg grating (FBG). Such a network can monitor the quasi-distributed dynamic strain of the structure online, which has some merits such as anti-electromagnetic interference, small size, and multiplexed. An estimation algorithm for the beam-like structure based on those strain measurements is also presented in this work. The performance of the proposed sensing network and deflection estimation algorithm was validated by a cantilever beam test rig excited by impulsive excitations in the laboratory environment. The experimental results illustrate the suggested monitoring system can monitor the bending deformation of the beam-like structure successfully.