Controllable Hierarchical Mechanical Metamaterials Guided by the Hinge Design

In this work, we use computer simulations (Molecular Dynamics) to analyse the behaviour of a specific auxetic hierarchical mechanical metamaterial composed of square-like elements. We show that, depending on the design of hinges connecting structural elements, the system can exhibit a controllable behaviour where different hierarchical levels can deform to the desired extent. We also show that the use of different hinges within the same structure can enhance the control over its deformation and mechanical properties, whose results can be applied to other mechanical metamaterials. In addition, we analyse the effect of the size of the system as well as the variation in the stiffness of its hinges on the range of the exhibited auxetic behaviour (negative Poisson's ratio). Finally, it is discussed that the concept presented in this work can be used amongst others in the design of highly efficient protective devices capable of adjusting their response to a specific application.

Automated summary

This study uses computer simulations to analyze the behavior and control of a specific anisotropic hierarchical mechanical metamaterial, showing that different hinge designs can achieve controllable deformation and enhance mechanical properties. The effects of system size and hinge stiffness variation on exhibited anisotropic behavior were also discussed. The concept presented could be applied in the design of highly efficient protective devices for specific applications.