Emergent functional dynamics of link-bots.

Synthetic active collectives, made of nonliving individuals that cooperatively change group shape and dynamics, hold promise for practical applications and understanding of their natural analogs. We investigate how simple steric interaction constraints between active individuals produce a versatile and functional system using the link-bot: a V-shape-based, single-stranded chain composed of active bots whose dynamics are defined by geometric linking constraints. A variety of emergent properties arises from this active polymer-like system, including locomotion, navigation, transportation, and competitive or cooperative interactions. By adjusting a few link parameters, we show how link-bots can perform diverse tasks, including traversing or obstructing narrow spaces, passing by or enclosing objects, and propelling loads in different directions. Overall, the reconfigurability of link-bots indicates their potential in developing programmable soft robotic systems with simple components and materials at any scale.