Research On Micro-vibration Isolation Methods For Spacecraft Onboard Equipments Based On Metamaterials

Spacecraft onboard equipments are mainly divided into precision equipments(such as space cameras,inertial navigation equipments,etc)and disturbance source equipments(such as thermal control equipments,etc).The disturbance source equipments are one of the main sources of the micro-vibration while orbiting,and the micro-vibration will seriously affect the performance of other precision equipments.Therefore,it is necessary to study the micro-vibration isolation of the spacecraft onboard equipments.Due to the band gap characteristic of metamaterials,the propagation of elastic wave on metamaterials can be attenuated during some designed range of frequency.And it can be applicated in the micro-vibration isolation for spacecraft onboard equipments,which has not been studied before.For this reason,the research on micro-vibration isolation methods based on metamaterials for spacecraft onboard equipments is carried out.Two micro-vibration isolators based on matemeterials are proposed,analysed and then verified by simulation.The main research work are summarized as follows:The vibration isolation demands of spacecraft onboard precision equipments and disturbance source equipments are analyzed respectively.The design requirments of the micro-vibration isolation device are put forward.And according to the support structures of the spacecraft onboard equipments,the configuration design of isolators are proposed.The bar of micro-vibration isolation truss is made of one-dimensional bipropellant rod-shaped phononic crystals.The band gap characteristics of the phononic crystals are studied,as well as the dynamic characteristics of the truss bar.Then comparing the dynamic characteristics and band gap characteristics,the isolator desing method based on band gap characteristics is proposed.Therefore,a model of micro-vibration isolation truss is established,and the simulation is carried out.The results show that the isolator has obvious attenuation effect on micro-vibration of 600-860 Hz and 905-1445 Hz,and its isolation performance is closely related to the band gap characteristics of one-dimensional bipropellant rod-shaped phononic crystals,verifying the correctness of method and device for micro-vibration isolation base on matematerials.The board of micro-vibration isolation framework is made of two-dimensional squre-lattice phononic crystals with cylindrical scatters.The band gap characteristics of the phononic crystals are studied,as well as the dynamic characteristics of the board.Then comparing the dynamic characteristics and band gap characteristics,the isolator desing method based on band gap characteristics is proposed.Therefore,a model of micro-vibration isolation board is established,and the simulation is carried out.The results show that the propagation of micro-vibration among the range of 1.44-3.16 kHz and 4.72-6.13 kHz is suppressed.Similarly,its isolation performance is associated with both complete band gaps and directional ones of XY mode and Z mode.These verify the correctness of method and device for micro-vibration isolation.