## Admission Requirements

BSc in Physics or similar

## Description

This course introduces and discusses the physical principles of mechanical metamaterials. Research on these metamaterials, whose properties depend on their geometric structure rather than their composition, has exploded in the last five years. Examples of such metamaterials include patterned elastic media and origami (folding) structures, leading to unusual negative response, programmable mechanics and shape morphing materials.

Using recent literature, we discuss these materials, as well as their underlying principles, which include (tensorial) elasticity and elastic instabilities, mechanisms, frustration and combinatorics: cool physics for new weird materials.

Each lecture deals with one or more recently studied mechanical metamaterial, and to understand their physics, the course introduces three more general topics:

- Introduction to linear elasticity

- Buckling and nonlinear instabilities

- Maxwell Counting, Floppy Modes and Self Stresses

After each lecture a set of exercises have to be made and one or two papers have to be read.

Each lecture a presentation is given by one of the students on these papers, followed by a general discussion in which active participation is required. The course is ended by a final short presentation on a student design for a metamaterial.

Specific topics that are covered:

- Introduction to elasticity, elastic constants, stress and strain, and auxetic metamaterials

- Elastic tensor, anisotropic elasticity, extremal and pentamode materials, mechanical cloak.

- Maxwell counting, floppy modes, and self stresses. Disordered metamaterials.

- Spontaneous symmetry breaking, Bending, buckling, holey sheet metamaterial

- Controlled symmetry breaking, nonlinear instabilities and programmable mechanical metamaterials

- Characteristic lengthscales

- Combinatorial design and metacubes

- Origami metamaterials, foldability

## Course objectives

Main learning objective of MSc course Mechanical Metamaterials: you are able to critically discuss the role of geometry in determining the effective properties of metamaterials.

Specifically, after this course, you are able to:

- Write down the elastic equations for complex and anisotropic materials and geometries.

- Perform scaling analysis for elastic constants etc.

- Analyze basic elastic instabilities.

- Analyze the degrees of freedom of complex hinged structures.

- Critically discuss the role of geometry in metamaterials

Moreover, you have acquired an overview of a very recent piece of literature.

## Soft skills

During this course you will be trained how to

- critically read research papers

- to present and discuss research work

- perform calculations on complex elastic structures

## Timetable

## Mode of instruction

Weekly lectures, exercises, paper reading and student presentations.

## Assessment method

Grading according to a weighted average of exercies and presentations

## Blackboard

Blackboard is used to distribute Course information

To have access to Blackboard you need a ULCN-account.Blackboard UL

## Reading list

not applicable

## Contact information:

Lecture

Prof.dr. Martin van Hecke