Design and selection of aluminum foam for impact damper of legged lunar lander

In order to find the appropriate cushion material which can absorb impact of legged Lander on its landing stage, some experiments were carried out to study the quasi-static and dynamic cushion properties of three kinds of aluminum honeycombs and four kinds of aluminum foams. After analyzing stress/energy-strain curves and cushion properties from the experiments, four kinds of characterization methods on cushion materials were put forward. These methods can evaluate the cushion properties comprehensively, and can be used to guide the design of legged Lander's impact damper. After analyzing and summarizing the cushion properties of tested aluminum honeycomb and aluminum foam with these methods, the coarsehole aluminum foam, with the nominal crushed strength of 0.140.15MPa, is proved to have the optimal cushion properties of all seven kinds of samples. The process of designing aluminum foam for impact damper of legged lunar Lander was put forward. Then, the impact damper for trussed lunar landing gear with four primary legs of HIT was designed with the coarse-hole aluminum foam, with the nominal crushed strength of 0.140.15MPa.