Structural Behaviour of a Cantilever Beam Consisting of Three Inflatable Cylinders

摘要

Inflatable spanwise cylinders are considered for the wing structure of small remotely piloted vehicles. A single cylinder with internal diaphragms was tested to find major differences compared with unreinforced cylinders. Three cylinders with internal ribs were combined into a single structure and tested for bending, torsion and combined loadings. Differences between the behavior of this structure and the single cylinder were observed and theories were developed to account for these differences. An outer covering was added, and a distributed loading was used to simulate aerodynamic loads. It is found that the addition of ribs to the single cylinder slightly improves stiffness compared with cylinders without ribs. The three cylinder structure behaves as expected and the theories developed to predict its structural behavior agree reasonably well with experimental results. The distributed loading does not produce any significant twist on the structure, which behaves as if it were subjected to bending only. The three cylinder structure is found to be a viable aerodynamic load bearing structure.