Vibration suppression of flexible structures continues to be a subject of considerable interest due to the increasing demands of high precision space applications. Large phased array antennas, for example, which are used for space-based radar system to track and identify moving objects, require high dimensional stability. The Air Force is interested is exploiting tension mechanics in maintaining dimensional stability of large array structures. To this end, this research investigates the problem of vibration suppression in a thin plate using in-plane tensile forces acting on the boundary. Earlier work has shown that the vibration of a cantilever beam can be effectively suppressed by end-forces and this work investigates the extension of the control strategy to the plate problem. Two scenarios are considered: one where the end-forces are uniformly distributed, and the other where the end-forces are applied at discrete locations using a web-of-cables structure. For the problem with uniformly distributed end-forces, both the Rayleigh-Ritz method and the finite element method are used to obtain the state space model of the system in modal coordinates. Simulations are then used to show the efficacy of the control strategy in reducing vibration. The plate with web-of-cables structure is modeled using the finite element method alone. The effect of the web-of-cables structure on in-plane stress distribution in the plate is determined and the pre-stress information is used to obtain the out-of-plane vibration model. The control method requires the tension in the corner cables of the web-of-cable structure to be switched and the efficacy of the control method is investigated for different switching algorithms. Numerical simulations for these different algorithms show that the control method is effective in suppressing the vibration of all modes except the first mode. This is due to the fact that change in the corner tensions is not effective in producing a significant change in the fundamental frequency. To suppress the vibration of the first mode, future work will have to focus on redesign of the web-of-cables structure relative to the plate dimensions.
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