Multifunctional Fluidic Units for Emergent, Responsive Robotic Behaviors

Fluidic circuits have shown significant promise in enabling complex functionality in soft robots with a minimal number of input signals. However, implementing complex behaviors typically involves numerous specialized components, resulting in intricate and nonversatile circuits. To address this challenge, a multifunctional fluidic unit designed to operate flexibly as a valve, sensor, or actuator is introduced. This unit provides an extensive design space that allows precise tuning to achieve the desired functionality. In particular, one configuration integrates all three functions simultaneously, resulting in a self-sensing oscillating actuator. By assembling multiple units—each customized for specific roles—complex robotic behaviors can be realized. The versatility and effectiveness of this modular approach are demonstrated by creating several robotic systems, including a controlled shaker, a multimodal hopper, and a crawler capable of sensing environmental boundaries. Furthermore, when these units are mechanically coupled via a shared body, it exhibit emergent passive behaviors, such as self-synchronization—a behavior that is elucidated with a Kuramoto model of networks of oscillators. This study highlights the potential of multifunctionality as a powerful and efficient strategy for realizing embodied intelligence in fluidic robotic systems.