Multifunctional robotic electrofluid for soft fluidic actuation

Like the vital role that multifunctional biological fluids play in living organisms, leveraging fluid multifunctionality offers a promising approach to enhance system capabilities without overcomplicating the hardware. However, creating a multifunctional fluid for soft fluidic systems remains a persistent challenge. Here, we report a multifunctional electrofluid that integrates actuation, sensing, self-healing, damage detection, and triboelectricity powering for the various function requirements of soft fluidic systems. We demonstrate that actuation, sensing, and damage detection can be achieved by activating electrons in the working fluid, and the system enables underwater self-healing through the incorporation of water-reactive self-healing agents into the working fluid. In addition, we achieve the fluid flow by transporting the electrons gathered by the triboelectric nanogenerator into the fluid, thereby making the system become a triboelectricity-powered machine. The fluid module developed based on electrofluids is self-contained and plug-and-play, providing good convenience for rapid construction of soft fluidic systems. We validate the effectiveness of the electronic fluids through soft robotic fish, soft octobot, and wearable devices, demonstrating that the proposed fluid enables multiple functions of the system without added weight or volume. As such, the proposed electrofluid provides a promising platform to achieve high integration and lightweight of multifunctional soft fluidic actuation by expanding the functionalities of the fluid itself.