Inspection on Buckling Mode of Crossed-Rib Reinforced Composite Laminates Panel by Fringe Projection Profilometry

Digital fringe projection profilometry (FPP) is suitable to inspect surface profile of object, with some apparent advantages of non-contact, full-field measurement, simple apparatus, high precision, and real-time profile automation. Four phase-shifted sinusoidal fringe patterns are circularly projected onto the surface of a composite laminates panel reinforced with crossed ribs. Phase shifting method is applied to inspect the surface profile variations during compression. The profile results reveal that different local buckling modes appear at different crossed ribs, where the wave villages locate at the middle and the wave peaks occur at the composite panel ends. From the details of the deflection analysis, it can be seen that the local buckling modes couple with the whole bending of the composite panel. The local buckling modes vary with the applied load and the experimental results are helpful to understand its failure mechanism.