Research

Our research is directed toward the design of advanced materials that exhibit unconventional mechanical responses. We harness the principles of geometry, symmetry, and the interactions of structural constituents to customize the collective properties of these materials.

In particular, we focus on engineered material systems, including auxetic materials, phononic crystals, and metamaterials, and take a mix of theoretical, numerical, and experimental approaches. We aim to leverage our fundamental understanding of these engineered materials to devise innovative solutions for advanced aerospace and mechanical systems.

Here are some of the exciting research directions we’re currently exploring:

1. Topological metamaterials

Metamaterials are artificial materials with properties not found in nature. Recently, there has been a tremendous effort in building a new class of materials with nontrivial topology. Usually, this property is calculated from the intrinsic dispersion of the system, and therefore, it is different from conventional material properties. At the physical level, topologically-nontrivial systems support robust energy localization on the boundaries of the material and have interesting directional properties.

We are interested in designing mechanical structures with nontrivial topology. The current efforts are towards understanding the role of topology in periodic, quasi-periodic, disordered, driven, lossy, and nonlinear systems.

(Top left) Design of a topological plate. (Bottom left) Demonstration of waveguiding across a channel between two topologically distinct plates. (Top right) Design of a Weyl structure. (Bottom right) Demonstration of robust waveguiding on its surface.
2. Nonlinear dynamics

Shock mitigation through a structure is often desired in various applications. Since the amount of energy in the system is large, the process generally involves nonlinear wave physics. Recently, there has been considerable interest in judicially designing nonlinear structures to control wave propagation in the medium. Not only material nonlinearities but also geometric nonlinearities can be harnessed to tune the dynamical properties of the system. The latter is especially relevant in the age of additive manufacturing by which complex geometries can be fabricated.

We are interested in exploring nonlinear wave phenomena in mechanical systems. In particular, we deal with lattice configurations so that we can invoke the effect of dispersion along with nonlinearity. The current efforts are to understand exotic wave mitigation/redirection properties of lattices. We also look at the fundamental physics of soliton formation and propagation of solitary waves in periodic and multi-stable lattices, for example, Origami lattices.

(Left) Woodpile crystal with the ability to tailor the impact due to the tunable nonlinear contact between constituents. (Right) A periodic lattice arrangement with the constituents being multistable.
3. Miscellaneous

Besides, we are also interested in exploring the following directions:

  • Fluid-metamaterial interaction
  • Active structures
  • Wave-based robotics
  • Machine learning for lattice structures