Highly efficient uncertainty analysis of an integrated vibration-isolating metastructure based on global sensitivity

Spacecraft actuators like control moment gyroscopes can generate micro-vibrations, which directly affect the imaging quality of space optical instruments and even the lifespan of key components of a spacecraft. Eventually, the key performance of the spacecraft can be affected. Although the integrated metastructure exhibits excellent vibration isolation ability, the manufacturing uncertainty on the complex geometry can affect the overall vibration isolation performance. In this paper, an efficient uncertainty analysis method based on global sensitivity was proposed, which can accurately quantify the vibration isolation performance deviation caused by the manufacturing uncertainty. First, an efficient global sensitivity analysis method was proposed by combining high-order sparse point interval Chebyshev polynomial expansion with variance-based Sobol, s sensitivity index. Comparing with the traditional Monte Carlo sensitivity analysis methods, this method improves computational efficiency by three orders of magnitude. Second, by ignoring the interval variables with smaller global sensitivity indices, the efficiency of the uncertainty analysis for complex metastructure s can be further enhanced. Finally, experimental validations were carried out. The results indicate that the proposed uncertainty analysis method based on global sensitivity can provide useful and efficient guidance for the design and manufacturing of vibration-isolating metastructures. © 2024 Chinese Vibration Engineering Society. All rights reserved.