Conventional optimal control theories usually deal with optimal control force that involves only structural information. In order to control the excessive vibrations of offshore platforms more effectively, this paper presents a control strategy, which employs both information of the controlled system and external loading, namely feedforward-feedback (FF-FB) control strategy. FF-FB control strategy requires that the input signal be a process of white noise for obtaining the optimal control result. So, an analog filter is designed in this paper to approximately represent the random wave force by a process of white noise. In order to investigate the feasibility and effectiveness of the proposed method, a numerical example applied to an offshore platform is presented in this paper. The numerical results demonstrate that the proposed method offers advantage in performance over the control method employing only state feedback.

This content is only available via PDF.
You do not currently have access to this content.