Intelligent design and experimental verification of functionally graded vibration-isolation and load-bearing structure

The installation of complex precision vibration isolation devices in spacecraft is frequently precluded by space and weight constraints. In this paper, a simple and reliable functional gradient beam vibration-isolation and load-bearing structure device is proposed for the vibration isolation requirements of micro-vibration sources such as spacecraft chillers, and a material-structure-function intelligent design study is carried out and experimentally verified. By introducing the vibration isolation mechanism of functionally graded materials and auxiliary mass to regulate the dynamic response of structures, an integrated vibration-isolation and load-bearing scheme of axial functional gradient (AFG) beams is proposed. The discrete dynamic equations of the system are established based on Timoshenko theory and the Chebyshev spectral element method. The influence of material gradient and auxiliary mass on the anti-resonance frequency is investigated theoretically to explore the regulating mechanism of the force transmissibility of the AFG beam vibration isolator. The integrated intelligent design of the AFG beam isolator, which encompasses material, structure, and function, is completed by utilizing a physical information neural network. In light of the discontinuous distribution of material volume fraction resulting from process limitations inherent to the actual sintering preparation of AFG beams, a high-consistency discrete stepped AFG beam was prepared through pressure infiltration technology. The theoretical and experimental evidence demonstrated that the discrete stepped AFG beam can be an effective alternative to the ideal continuous AFG beam in structural vibration control. The vibration experiment corroborates the viability of the vibration isolation principle, the veracity of the theoretical model, and the efficacy of the design outcomes. The vibration isolator achieves a vibration attenuation of over 98% while maintaining a load-bearing stiffness of <sc>195 kN/m.</sc>