Micromechanically informed generalized continuum models can serve as an effective basis for discovering and conceiving exotic and viable metamaterials. Such an approach is in contrast to the current approach in which metamaterial discovery typically proceeds from a “trial and error” or “ad hoc” proposition of periodic microstructure often based upon prior experience or judgement. Here, we describe an effort in which a non-standard micro-polar (Cosserat) continuum model derived based upon the granular micromechanics approach (GMA) has been utilized to conceive metamaterials with mechanical chirality and auxetic response. In particular, we investigate a granular motif formed of an orthotropic arrangement of grains, in which grain-pair are linked with mechanisms directly suggested by the GMA based non-standard micro-polar model. In this short paper, we address two questions: one, we examine via classical Finite Element model if the conceived systems can be treated as granular materials; and two, using parametric study we investigate if the emergent macro behavior can be tuned by varying micro-characteristics.
