Mechanical and Civil Engineering Seminar

Materials, structures and systems that are capable of shape adaptation exhibit multifunctionality capitalizing on their ability to adopt different geometrical configurations. Biological system are masters in exploiting adaptation to operate in unstructured environment fulfilling dissimilar functions. Recently, the idea of rendering engineering systems adaptable and multifunctional has resulted in a diversity of research fields, such as soft robotics, adaptive structures and programmable metamaterials. The multifunctionality and adaptability stems from the intimate relationship between property, form and function in which any variation in one results in changes in the other. An interesting avenue for exploiting this relationship utilizes large deflections arising from elastic instabilities. In which the careful design of such nonlinear systems enables the possibility for programming functionality into systems. Indeed, systems exhibiting geometrical multi-stability, the switching between the available stable configurations from compliance, naturally show fast adaptability of shape and stiffness which may be triggered by active control or passive response to environmental changes. The arrangement of hierarchical multi-stable elements into compliant structures is an exciting methodology for creating architectured material systems and structures with inherent multifunctional behaviour.

This seminar will present examples in which hierarchical structures exhibiting multistability result in programmable structures. Two classes of systems will be presented: 1) bioinspired self-shaping structures that can significantly alter their shape and properties; and 2) Nonlinear metamaterials exhibiting unconventional dynamical properties.