Biological collective systems can achieve scalable and adaptive group behaviors, optimizing to complex and dynamic environments through local sensing and interactions. For example, consider how light/load sensitive cells in can control and optimize entire plant growth for sunlight or for difficult terrains. Can we program multi-agent systems, like modular robots, to adapt to dynamic conditions like living systems using only decentralized interactions?

We can! Our group developed a bio-inspired control framework for Distributed Homeostasis -- a type of task in which agents must use distributed sensing to solve collective tasks and to cope with changing environments. We show how one can exploit the locality of this formulation to design nearest-neighbor agent control, based on simple sensing, actuation and local communication. This task space can be formulated more generally as distributed constraint-maintenance on a networked multi-agent system, and this formulation allows us to prove many important theoretical guarantees such as correctness and scalability.

It allows us to capture various multi-agent scenarios and many application areas. As part of this project we built many different types of modular robots, from self-adapting tables and walkways based on chain-style modular robots, to linkage-based deformable robots that move through rolling and locomotion waves. This work also started the Wyss Project on Programmable Active Soft Orthotics to design rehabilitation orthotics for kids (with cerebral palsy) or stroke patients to help promote normal gait development, by adapting and compensating for neuromuscular disorders. We developed several prototypes, and this work is now being led by Conor Walh's lab.

Awards: Chih-han Yu received the runner-up prize for the 2010 Victor Lesser Distinguished Dissertation Award for his PhD Thesis at AAMAS 2011.

Movies: SSR ModularRobots Youtube Channel, Check out videos of these cool robots!