Structural swinging motion and its control subject to point source input

![CDATA[Aiming at the practical problem of swinging motion control of hook and similar suspended structure, the innovative Tuned Rotary Inertia Damper (abbreviated as TRID) control system for pendular vibration suppressing, which is based on passive tuning and absorbing control principle, has been proposed recently by structural control group in Harbin Institute of Technology. As an extension to this problem, parameter optimization and impact of control efficiencies subject to point source excitations, e.g. barge ships subject to ocean wave excitations, are carried out in this paper. Firstly, equation of motion for the suspended structure under arbitrary motion excitation is established based on Lagrangian principle, and the theory of TRID control system is analyzed. Secondly, numerical simulation of TRID control for two types of suspended structural motions, planar pendular vibration and spatial cone motion, is conducted, respectively. Then, optimal parameters and impact factors are summarized. Lastly, the abnormal phenomenon of TRID control for structural response in the resonant zone is studied. The combined TRID-TMD control system for suppressing the ideal cone motion mode is proposed to overcome the limitations of single TRID control system, and the effectiveness and feasibility are validated through numerical analysis. The research result of this paper establishes a partial theoretical foundation for anti-swaying of hook structures of large-scale heavy-lifting and pipeline-paving barge ships, subjected to ocean wave excitations.]]