Analysis Of Vibration Transmission Characteristics And Vibration Isolation Of Typical Satellite Connection Structure

During the normal orbit of the satellite,disturbance sources such as flywheels and driving mechanisms continuously transmit vibration energy to the star body and its connected equipment,causing the star to shake and reduce the working performance of the payload.The research and suppression of micro-vibration has become a topic that needs attention in the development of high-precision aerospace equipment.In order to study the propagation law of vibration energy in the spacecraft and its suppression methods,this paper uses wave theory to study the vibration propagation law in the coupling plate based on several typical thin plate connection methods that constitute a complex spacecraft,and isolates the vibration-damping mass.The technology is applied to the vibration suppression of the connecting plate.First of all,this article is based on the typical semi-infinite-length plate connection structure,considering the connection nodes that are not completely rigid,and uses the wave theory to establish a dynamic model of the connection structure.Through simulation examples,the vibration energy transfer characteristics in the connection structure and the influence of the stiffness and damping of the connection nodes on the transmission of vibration waves are analyzed.Studies have found that bending waves carry most of the energy in the structure,which is the main wave type that causes structural vibration;the energy carried by high-frequency vibration in the coupling structure is more transmitted downstream through the connection structure;when the stiffness of the connection node is low There is an impedance matching frequency at which the amplitude of the flexural wave impedance matches the amplitude of the connection stiffness impedance,and the flexural wave transmission efficiency drops rapidly.Secondly,a traveling wave dynamics model is established for two vertically connected finite-length coupled thin plates.In this model,the plate boundary is considered as an elastic support,and the connecting line of the two plates also has a certain degree of rigidity and structural damping.Given the specific initial conditions of the model,the influence of the boundary conditions,the stiffness of the connection between the two plates and the excitation type on the transmission of vibration waves in the plate is analyzed.The study found that high-frequency vibration is sensitive to boundary conditions,and small differences in boundary conditions will cause huge changes in the structural response;when multiple excitation sources in a plate structure are mixed,the contribution of each excitation to the plate vibration displacement is different,unit torque and unit When the forces are acting simultaneously,the moment of force plays a leading role in the vibration of the structure.Then,based on the analysis of the vibration transmission characteristics in the finitelength coupled plate structure considering the connection stiffness,the application of the vibration-damping mass vibration isolation technology in the vertical connection plate is studied.The analysis found that the vibration isolation effect of the vibration-damping mass is limited;changing the layout and cross-sectional shape of the mass can improve the vibration isolation effect,but it is not very obvious.In order to improve the vibration isolation effect,the active control of power flow is combined with the vibration-damping mass vibration isolation technology and its vibration isolation effect is analyzed.Finally,in view of the problem of vibration suppression in the satellite frame structure,the application of multi-stage vibration isolation and combined damping layer composite vibration isolation method is studied.The study found that the combined vibration damping method of vibration damping mass + local damping has better vibration suppression effect than the method of independent vibration damping mass and overall damping.