Nonlinear deformation of thin-walled structures for deployable and morphing applications

这个博士项目关注薄壁结构的非线性变形，可展开和变形的应用。以前的研究已经确定了两个值得注意的元素;所谓的“带弹簧”和波纹板。两者在日常生活中都很常见，分别作为卷尺和屋顶元件。如果它们做得足够薄，它们可以弹性弯曲并以局部方式变形;如果预加应力（通过塑性加工），它们在变形状态下可以是双稳态、三稳态甚至中性稳定的。本项目旨在探索带状弹簧和波纹板的通用版本。第一方面提出制造"带环"-代替直的，带弯曲以形成环，导致开放的环形形状。Seffen的初步有限元分析已经确定，带环以与带弹簧相同的方式弯曲，但形成两个折痕，然后可以围绕环移动，从而实现一种零刚度旋转动作。然后，该项目将考虑如何将带环作为重复的平面单元互连，以形成具有局部纹理和孔的板。据推测，相互作用的单位将提供不寻常的和新颖的，大变形的板整体。该项目将结合联合收割机的实验，制造，计算研究和数学分析。该项目属于结构工程研究领域的福尔斯。

This PhD project concerns the nonlinear deformation of thin-walled structures for deployable and morphing applications. Previous research has identified two notable elements; so-called "tape-springs" and corrugated sheets. Both are familiar in everyday life, as tape-measures and as roofing elements, respectively. If they are made to be sufficiently thin, they can buckle elastically and deform in a localised manner; and if pre-stressed (by means of plastic working), they can be bistable, tristable or even neutrally stable in their deformed states. This project aims to explore generalised versions of tape-springs and corrugated sheets. The first aspect proposes to make a "tape-ring" - instead of being straight, the tape curves around to form a ring, resulting in an open toroidal shape. Preliminary finite element analysis by Seffen has established that a tape-ring buckles in the same way as a tape-spring but forms two creases, which can then travel around the ring, enabling a type of zero-stiffness spinning action. The project will then consider how to interconnect tape-rings as repeating planar units, in order to form a plate with local texture and holes. It is surmised that the interacting units will proffer unusual and novel, large deformations of the plate overall. The project will combine experiments, manufacturing, computational study and mathematical analysis. This project falls within the Structural Engineering research area.