Mechanical Properties Of The Vibration Isolation And Mitigation Device And Analysis Of The Controlled Structure

Loading platform is the working supporter of special equipment, and its bearing capacity sometimes can reach generally greater than normal. The working environment is very complex, the excitation has the characteristics of wide frequency range (0～500Hz), the vibration of the loading platform is very complex, and multi-direction vibration happen at the same time. All the disadvantages will influenced the accuracy and useful life of the special equipment. Therefore, the vibration control requirement need a better performance in wide frequency range and high stability. How to make the loading platform meet the requirement of vibration isolation and mitigation (VIM), is a challenge to the performance of the VIM device, application of high-energy-dissipation materials and design of structure. So many problems call for urgent solution.This paper was aimed at the new type VIM device used for the loading platform, including mechanic property analysis of the VIM device, the analysis of mathematical model and the dynamic response analysis of the VIM system of loading platform. Then the research work was carried out according to aspects above based on the recent progress domestic and abroad.1. According to the working characteristic of the loading platform, a new type VIM device was proposed. The device is composited with the technology of visco-elastic damper, viscous liquid damper and air spring. This device has good vertical VIM performance. At the same time, this device can be used for the loading platform because of its good mechanical stability.2. The experimental data of the vertical properties of the VIM device was analyzed in this paper. The experimental results reveal that both excitation frequencies and displacement amplitudes have remarkable effect on the mechanics parameters of the VIM device. Additionally, the shear storage modulus, loss modulus and loss factor increase with the increasing frequencies and decrease with the increasing displacement amplitudes, while the single loop energy dissipation increases with displacement amplitudes.3. The commonly used mathematical models of the viscoelastic material were reviewed. In order to determine the mechanics of the VIM device preferably, a mathematical model that considered the contribution of the visco-elastic material, viscous liquid and air spring, was proposed in this paper. Then it was compared with the test results.4. The suitable parameters of the VIM device were chose based on the mathematical model of the VIM device. The dynamic model of the loading platform with the VIM device was established, and the dynamic response analysis of the loading platform under multi-shock was completed in MATLAB. The results show that the dynamic response of the excitation can be effectively reduced.