Herez(t)andz(t)are internal state vectors and theA`, B`, C` and D` are constant matrices.The
validation of the separate aerodynamic and hydrodynamic models is presented byCollu et al.[17].
BlusseauandPatel [18] found that the gyroscopic forces induced by the coupling between arotating
VAWT and moving platformaffect the overall system motions. The gyroscopic forcesshall be
represented by dampingcoefficients in pitch and roll. The gyroscopic moments in roll and pitch are given
by Equations 3and4,respectively: