The main hypothesis in this work is that structural instabilities, in single microbeams and assembled structures, can be tailored to build in computational capabilities into structural systems, thus mimicking advanced circuitry functionalities using only mechanical loading in structural elements. In this thesis, we demonstrate the possibilities of solving complicated fourth order partial differential equations using potential energy optimization in axially loaded beams. A similar concept to the minimum energy path in analog circuitry. The proposed approach relies on controlling the post-buckling instability of elastic Euler-Bernoulli beams subjected to gradually increasing loading. The focus in the first few chapters in this thesis, is to study novel methods to tailor and control the mechanical response of anisotropic bilaterally constrained beams with arbitrary cross-section geometries. In particular, theoretical models are developed, using the small deformation theory assumptions, and the static post- buckling behavior of the elastic beams is analyzed using the energy method. Non- prismatic and Functionally-Graded Materials (FGM) beams are studied with respect to several parameters and effects (i.e., beam shape configurations, materials, geometric properties). Effective control levels over the post-buckling behavior, of the bi-walled beams, were achieved. In addition, the manufacturing of the structural system was studied using 3D printing techniques. It was demonstrated that by tuning the beams' parameters (material and geometry), the snap-through transition events between post-buckling configurations (i.e., sudden energy release), can be configured to happen at specific times (during the loading stage), and that the generated energy output can be controlled. This principle is the main concept used to implement multifunctional capabilities in structural systems.
Read
