Photoresponsive Valves for Soft Robotic Actuation

In the growing field of soft robotics, researchers are continuously exploring new ways to make robots move. A promising approach involves incorporating materials that react to stimuli like pH, temperature, light, and magnetic field into soft robots to achieve better control and manipulation [1]. Among these intelligent materials, light-responsive hydrogels have garnered significant attention [2]. One example is the copolymerization of PNIPAM with spiropyran, a photoresponsive molecule that transitions to a hydrophobic state upon illumination, leading to the shrinkage of the hydrogel [3]. This light-triggered response has the potential to enable non-invasive, cost-effective, and remotely controlled actuation. In the medical field, hydrogels that respond to light could be used to develop advanced drug delivery systems and novel actuation strategies for soft endoluminal robots, enhancing safety and efficacy in navigating the human body. While light-responsive hydrogels have been used to create microvalves for microfluidic devices [4], their translation to the macroscale remains largely unexplored. Here, we present a novel method for designing and fabricating photoresponsive valves embedded within soft channels for controlling soft robotic actuators. The characterization of the photoresponsive valves’ response time was investigated and showed promising results