Growing and evolving soft robots with a face-encoding tetrahedral grammar

In this work we describe how the morphology of mobile soft robots can be evolved using a grammatical encoding operating on tetrahedral meshes. Actuation of the soft bodies is achieved by uniformly cycling tetrahedral stiffness. Evolved morphologies exhibit functional differentiation across body regions, and the grammatically derived phenotypes exhibit stable fitness across a range of their ontogenic trajectory, suggesting scalability.