Phase Transition-Based Portable Pump for Modular and Reconfigurable Soft Robotic Devices

Fluidic elastomer actuators have emerged as one of the most promising candidates for modular and reconfigurable soft robotics devices, especially for wearable and healthcare applications, due to their inherent compliance, robustness, cost-effectiveness, and ease of fabrication. However, a significant challenge in the widespread adoption of fluid-driven soft robots is their reliance on bulky and heavy external pumps and compressors, which fundamentally limit their portability and versatility. To address this challenge, our research introduces an approach utilizing the liquid-vapor phase transition of a low-boiling point liquid to develop a portable pump, without using any rigid mechanical moving component. This low voltage-driven electrothermal pump employs the Peltier effect for rapid and reversible active heating and cooling, allowing for more efficient heat transfer compared to joule heating and natural passive cooling. A maximum output pressure of 43.2 kPa and a maximum flow of 72 ml/min is achieved using a battery. This pump stands out for its portability, versatility, and potential to function as a modular self-contained fluidic source for soft robots. It is poised to revolutionize various applications, including home-based wearable devices, thermally active clothing, and autonomous untethered soft robots.