Structural Damage Detection of Spacecraft Equipment Based on Data Driven Modelling and Nonlinear Output Frequency Response Function

Damage detection of the spacecraft equipment is required in vibration test to avoid the costly spacecraft equipment worsening of damage. The current method is to compare the change of the natural frequencies, which may be failure because linear feature is usually not sensitive to some damage. The objective of this study is to develop a novel structural damage detection method of spacecraft equipment to address the current method problem. To achieve this goal, use regularization FROLS (Forward Regression Orthogonal Least Squares) algorithm to identify the NARX (Nonlinear Autoregressive with Exogenous Input) model of the spacecraft equipment. After that, use the theory of NOFRF (Nonlinear Output Frequency Response Function) under harmonic input to obtain the NOFRFs, which can be used to detect the damage of spacecraft equipment in vibration test. Finally, an experimental study is carried out to conduct damage detection for a cantilever plate structure to demonstrate the effectiveness of the proposed method in engineering.