Available student project - Motions of crystalline bar-joint frameworks

Research fields

  • Topological and Structural Science
  • Theoretical Physics
An elastically-isotropic rigid framework

Project details

Crystalline frameworks (nets) are a standard model of three-dimensional periodic structure in materials. To first order, the allowed motions of framework structures can be modelled as perfectly stiff beams joined at freely-pivoting junctions. Recent work by Power et al, has shown that the low-energy (soft) deformation modes of such a crystalline framework are characterized by a matrix function and its points of rank degeneracy. The associated geometric flex spectrum helps us determine the possible existence of surface modes: a mechanical analogue of topological insulator materials. 
 
This project will compute the first-order geometric flexes of a suite of crystalline frameworks in the EPINET and RCSR databases.  We will look for signatures of different categories of motions such as rigidity, one-degree-of-freedom structures, auxetic deformations, and surface modes. 

Required background

This project involves advanced applied mathematics (e.g. linear algebra, tangent spaces) and requires computations and coding in a high-level scripting language such as python. 

Project suitability

This research project can be tailored to suit students of the following type(s)
  • 3rd year special project
  • PhB (2nd or 3rd year)
  • Honours project

Contact supervisor

Robins, Vanessa profile

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