November 28, 2015

Vibration Control of Massive Structure

Vibration Control of Massive Structure

Study of heat-driven vibration of spacecraft based on absolute coordinate


We studied the heat-driven vibration of spacecraft under the load of sun's heat radiation. For large circular antenna and spin stabilized spacecraft with hangar rod along axis, we applied absolute node coordinate method and natural coordinate method to heat-structural dynamics coupling analysis, and found out that orbiting spacecraft may suffer heat vibration under heat load. Besides, in order to depict cross section deformation of beam structure in motion, we introduced beam unit considering cross section distortion effect based on absolute node coordinate method.

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Z. X. Shen, P. Li, C. Liu, and G. K. Hu, A finite element beam model including cross-section distortion in the absolute nodal coordinate formulation, Nonlinear Dynamics,77, 1019-1033, 2014

Vibration control of flexible rope based on wave motion control


With the development of space engineering, many massive flexible structures have been used in space, such as mechanical arms of space station and solar panels. Flexible structures are massive and lightweight with low damping feature, thus in motion they will have severe residual vibration which may last long. This will have huge impact on flexible parts efficiency, and may cause failure.

Wave motion control is effective in flexible structures. Based on previous control method of homogeneous structure, we set double pendulum and distributed mass as our researching targets. And by applying reflection absorbing method, we introduced open loop control law of inhomogeneous structure, then validated this law through numerical simulation and experiment. Results showed that, comparing with no control condition, residual vibration amplitude is 10 times less.

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