Probabilistically-robust nonlinear control of offshore structures

Abstract

A controller design for offshore structures is discussed in this study. Stochastic simulation is considered for evaluation of the system's performance in the design stage. This way, nonlinear characteristics of the structural response and excitation are explicitly incorporated into the model assumed for the system. Model parameters that have some level of uncertainty are probabilistically described. In this context, the controller is designed for optimal reliability, quantified as the probability, based on the available information, that the performance will not exceed some acceptable bounds. This treatment leads to a robust-to-uncertainty design. The methodology is illustrated in an example involving the control of a Tension Leg Platform in a random sea environment. Multifold nonlinearities are taken into account for the evaluation of the platform's dynamic response and a probabilistic description is adopted for characterizing the random sea environment.

Files

Additional details