Study on the Influence of Soil Parameters on the Cushioning Performance of Landing Airbags

To investigate the influence of soil parameters on the cushioning performance of landing airbags, a landing airbag cushioning dynamics model considering soil characteristics was established based on the control volume method and a crushable foam model. Experimental validation was conducted for both the airbag cushioning model and the soil impact model, respectively, with good consistency between simulated and experimental results. Based on the established model, the influence of soil on the cushioning performance of landing airbags was analyzed. The analysis results indicate that soil absorbs energy through compressive deformation during the cushioning process, thereby exhibiting a certain degree of cushioning performance. Softer soil absorbs more energy, and the payload is less prone to rebound. However, excessively soft soil causes the airbag to sink into the soil, hindering the venting of gas outward and resulting in hard landings for payloads. Therefore, three indicators—airbag peak pressure, payload maximum acceleration, and maximum drop height—are used to comprehensively evaluate the cushioning performance of airbags, and the influence laws of soil parameters are quantitatively researched. The research shows that the soil density, shear modulus, and yield parameters A1 and A2 significantly influence cushioning performance. Specifically, the shear modulus and yield parameter A1 exhibit logarithmic growth relationships with the three cushioning performance indicators, while the yield parameter A2 and soil density show linear growth relationships with the three cushioning performance indicators.