Roll response of semisubmersibles with non-linear restoring moment characteristics

This paper investigates the dynamics of a semisubmersible model with an inflectional restoring moment. Insight into the system's behaviour is given by an approximate analytical solution and time domain numerical solutions. Poincare mapping techniques are used which show regions of chaotic motions in response to harmonic excitation. Results are presented and discussed within the physical applications of the model.