Date of Award
Master of Science (MS)
Oliver Jermaine Myers
Recently, multi-stable origami have drawn many attentions for their potential applications in multi-functional structures and material systems. Especially, origami folding is essentially a three-dimensional mechanism, which induces unorthodox properties that distinguish this mechanism from its traditional counterparts. This study proposes a multi-stable origami cellular structure that can exhibit mechanical diode behavior in compression. Furthermore, with a small variation in the unit cell of the proposed structure, a extension diode can be achieved. Such structures consist of many stacked Miura-ori sheets, and can be divided into unit cells that pose two different stable configurations. To understand and elucidate the underlying mechanisms, two adjacent unit cells were considered as the most fundamental constituents of the cellular structures that display the desired diode behavior. This study examines how folding can impose a kinematic constraint onto the deformation of these two dual cell chains via estimating the elastic potential energy landscapes of two dual assemblies. For the compression diode, this folding-induced constraint increase the energy barrier for compressing from a certain stable state to another, however, the same constraint does not increase the energy barrier of the opposite extension. Thus, one should apply a large force to compress the chain, but a small force to extend it. As a result, a compression mechanical diode is achieved. This constraint acts the opposite way in extension diode. Then, four prototypes were fabricated to experimentally validate the analytical results. The results of this study can open new avenues towards multi-functional structure and materials systems capable of motion rectifying, wave propagation control, and even mechanical computation.
Baharisangari, Nasim, "Exploiting the Asymmetric Energy Barrier in Multi-Stable Origami to Enable Mechanical Diode Behavior" (2020). All Theses. 3390.