Active Foam: Connecting Structure, Dynamics and Control

By inflating and deflating voxels within a polydisperse 2-D air-liquid foam, we demonstrate a system where we perturb soft materials in a radially-symmetric manner. These cyclic perturbations can be coordinated spatially and temporally to encode ("write") mechanical properties into the material. In addition to experiments, we will discuss a new simulation method used to test distributed local control strategies to achieve global behavior. We can estimate where regions of topological rearrangements occur by connecting microstructural mechanics with the dynamics of slowly oscillating sources and sinks in the material. We address the significant complexity that arises from polydispersity and initial topological disorder. The goal of this work is to understand fundamental principles of confluent tissues and develop functional synthetic analogs.