Analysis of a Celestial Icosahedron

Abstract

This paper presents the experimentation and finite-element analysis of a unique structure called a celestial icosahedron. The structure is being considered in a project related to lighter-than-air vehicles. The dimensions of the vehicle are adjusted to fit into an additive manufactured facility. A celestial is made up of nine rings symmetrically placed in a spherical arrangement. This is one of several structures that have been considered in the overall project. The uniqueness of this structure lies in its makeup; nine rings combined together through an additive manufactured (AM) facility. The structure was experimentally loaded in a MTS Systems Corporation machine under a concentrated compression load. A finite-element analysis was carried out, and the results compared with the experiment. The model considers the effect of anisotropic characteristics through the use of the rule of mixtures based on the presence of compression and tension moduli in specific portions of the load distribution yielding a generalized effective modulus. It was found, with the use of commercially available software, that the results of nonlinear analysis compared reasonably well with the experimental findings.