  Robotic materials are multi-robot systems formulated to leverage the
low-order computation and actuation of the constituents to manipulate the
high-order behavior of the entire material. We study the behaviors of ensembles
composed of smart active particles, smarticles. Smarticles are small, low cost
robots equipped with basic actuation and sensing abilities that are
individually incapable of rotating or displacing. We demonstrate that a
"supersmarticle", composed of many smarticles constrained within a bounding
membrane, can harness the internal collisions of the robotic material among the
constituents and the membrane to achieve diffusive locomotion. The emergent
diffusion can be directed by modulating the robotic material properties in
response to a light source, analogous to biological phototaxis. The light
source introduces asymmetries within the robotic material, resulting in
modified populations of interaction modes and dynamics which ultimately result
in supersmarticle biased locomotion. We present experimental methods and
results for the robotic material which moves with a directed displacement in
response to a light source.
