The demand for tailor made light weight structures in aerospace, defence and automotive sectors have been met by composite materials and are being extensively used.This is due to high strength and stiffness to weight ratio, lower cost of manufacturing of the composite structures.The composite structures used are anisotropic and are characterized by bending-stretching coupling.Often these structures are subjected to severe environmental conditions which necessitate study of their behaviour in the nonlinear domain.Solar panels and aircraft wing panels made of angle ply and cross ply laminates undergo nonlinear vibration due to large amplitude motions.The restoring force function in this case has been found to be a cubic polynomial yielding a Duffing type equation or has a combination of quadratic and cubic terms.Chaotic vibrations of composite plates subjected to harmonic excitation have also been analysed [1].