Impact performance of curved double arrow and stacked Miura-ori panels

The design methods for creating curved stacked structures of double arrow and Miura-ori are proposed and the impact performances of the two novel curved sandwich panels with double arrow and stacked Miura origami core are examined respectively for the first time. A specimen of curved double arrow panel is prepared and subjected to impact testing using a drop weight impact system and the test results are then used for validating the numerical models. Numerical simulations are conducted to examine the impact performance of the proposed curved double arrow and stacked Miura-ori sandwich panels for the first time. Additionally, existing curved honeycomb panels with the same core densities are analyzed for comparison. Various impacting scenarios, including different impact speeds, impactor shapes, and impactor dimensions are considered. Key performance indicators such as indentation depth, back plate deflection, energy absorption, deformation mode and impact force-displacement curves are utilized to assess the impact resistance of the three curved sandwich panels. The curved panel with stacked Miura-ori core exhibits superior performance across most impact scenarios, attributed to its relatively high crushing resistance and the constraining effects from adjacent unit cells. The double arrow curved panel demonstrates good performance against spherical projectiles at high impact velocities due to its long unit cell in the longitudinal direction, leading to a delayed rupture of the skin plates. Both curved double arrow and stacked Miura-ori panels show lower sensitivity to the variations in impact scenarios than curved honeycomb panel, indicating a promising impact-resistant application potential for structures with curved surfaces such as train and airplane.