Engineers at the Korea Advanced Institute of Science and Technology (KAIST) have developed a multifunctional soft material capable of detecting nearby objects and grasping them through light-induced reconfiguration. Known as the Ionograsper, this innovation integrates sensory and mechanical functions into a single polymer, effectively eliminating the need for discrete sensors and actuators that traditionally complicate soft robotic architectures.
The research, published in the journal Advanced Materials on September 29, 2026, details how the team synthesized a material that responds to both electrical fields and ultraviolet light. By combining azobenzene with a hygroscopic polymer, the researchers created a network that facilitates ion mobility, allowing the material to detect charged objects through internal ion redistribution without requiring external power for sensing.
When an electrically charged object approaches, the resulting electric field shifts the positive and negative ions within the polymer matrix. This internal movement generates an electrical signal that serves as a proximity sensor, providing the robot with environmental awareness. The system operates autonomously, detecting movement without the application of a separate sensing voltage.
Actuation is achieved through exposure to ultraviolet light, which triggers a molecular shape change in the azobenzene component. This process induces moisture loss on the irradiated side of the material, causing it to bend toward the light source to grasp a target. The material exhibits a unique structural memory, retaining its deformed grasping shape for over 10 minutes after the light source is removed.
The mechanism behind this shape retention involves the formation of nanoscale pores on the surface during irradiation, which allow moisture to re-enter the material once the light is extinguished. This rehydration process causes the polymer to bend in the opposite direction, slowly relaxing the structure back to its original state. This inherent structural reconfiguration allows for sustained grasping without continuous energy input.
Professor Hong Chul Moon, who led the team from the Department of Chemical and Biomolecular Engineering at KAIST, emphasized that the design significantly reduces the wiring and component density typically required for soft robotics. By merging the roles of skin and muscle, the Ionograsper streamlines the physical complexity of robotic hands. The study was co-authored by Professor Yong Min Kim of Jeonbuk National University, who served as the first author.
The current iteration of the Ionograsper functions as a proof-of-concept for integrated physical intelligence. While the material successfully demonstrates proximity sensing and bidirectional actuation, the researchers acknowledge that further development is required to optimize performance for practical applications. Future iterations will focus on increasing the sensing range and actuation speed while improving the material’s load-bearing capacity and durability under repeated use.
The research team is also exploring methods to broaden the spectral response of the material beyond ultraviolet light. Shifting the sensitivity toward visible or near-infrared light would enhance the utility of the Ionograsper in diverse operational environments. These improvements are essential for transitioning the technology from laboratory testing to real-world integration in soft robotic systems.
The broader objective involves incorporating the material into advanced physical AI architectures. By pairing the Ionograsper with sophisticated control algorithms, the researchers aim to create robots that possess both the tactile sensitivity and the mechanical dexterity required for complex tasks. This development represents a shift toward material-level intelligence, where the physical properties of the robot contribute directly to its functional capabilities.
The path to commercial or industrial deployment remains contingent on overcoming existing limitations in response time and durability. As the team refines the polymer chemistry, the focus will remain on balancing the sensitivity of the ion-redistribution mechanism with the structural integrity of the grasping action. These milestones will determine the viability of the Ionograsper as a foundational component for the next generation of autonomous soft robotics.