A kinetostatic conceptual framework to design deformable mechanical metamaterials

"Mechanical metamaterials have been gaining much interest in the field of material design for their unique attributes such as light weight, high strength, enhanced energy absorption, high impact, and fracture resistance. The behavior of such materials is governed by their structural geometry rather than their chemical composition. Metamaterials generally have two or more levels of hierarchy with a global topology combined with geometric intricacy at constitutive unit cells. The design of mechanical metamaterials is usually limited to structures that bear loads with little deformation. Furthermore, the design methodologies in literature are dominated by numerical approaches that are computationally expensive with limited user insights of the obtained solutions. In such a context, this thesis presents a novel alternative framework for the design of mechanical metamaterials in planar and spatial domains, and also for the design of planar mechanical metamaterials that undergo a prescribed deformation behavior. Such deformable metamaterials are deemed useful in shape morphing of airfoils, compliant mechanisms, wearable medical devices, stretchable electronics, and soft robotics. Design of deformable mechanical metamaterials is challenging because it requires considering the topology and deformations at different hierarchical levels, and there are no systematic design frameworks that preserve the intuition of the designer while delegating the tedious task of optimization to a computer. This thesis proposes a mechanics-based kinetostatic framework that enables visualizing forces flowing through the constituent structural members. The nature of load flow can be used to make design decisions to determine kinematically feasible deformable topologies using generalized guidelines. The design methods can be used to generate multiple viable solutions with relative ease using just a ""pen and paper"" for planar topologies and a customized ""virtual reality"" tool for complex spatial topologies. The kinetostatic methodology also enables qualitative classification of the entire design space, and these qualitative classes allow intuitive and computationally less intensive solutions for deformable mechanical metamaterials. The feasibility of this technique has been demonstrated through the design of several novel deformable mechanical metamaterials."

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Systems & Entrepreneurial Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2020

Author dc:creator

• Patiballa, Sree Kalyan

Contributors dc:contributor

• Krishnan, Girish
• Allison, James
• Wang, Pingfeng
• James, Kai

• Auxetics
• Mechanical Metamaterials
• Homogenization
• Poisson’s ratio
• Virtual Reality
• Compliant mechanisms
• Shape morphing mechanisms

Statement dc:rights

• Copyright 2020 Sree Kalyan Patiballa

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/107939

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/107939