Abstract— This paper presents a novel biologicallyinspired hierarchical approach to organizing and controlling modular robots. The purpose of our approach is to decompose the complexity of assembling and commanding a functional robot made of numerous simple modules (thousands to millions) by introducing a hierarchy of structure and control. The robots we describe incorporate anatomically-inspired parts such as muscles, bones and joints, and these parts in turn are assembled from modules. Each of those parts encapsulates one or more functions, e.g. a muscle can contract. Control of the robot can then be cast as a problem of controlling its anatomical parts rather than each discrete module. We show simulation results from experiments using gradient-based primitives to control parts of increasingly complex robots, including snake, crawler, cilia-surface, armjoint-muscle and grasping robots. We conclude that this approach is promising for future many-modules systems, but is currently imp...