Soft inflatable robots have emerged as a promising breakthrough for applications demanding safety and adaptability.
A research team jointly led by Professor Jiyun Kim (Department of New Material Engineering, UNIST) and Professor Jonbum Bae (Department of Mechanical Engineering, UNIST) has unveiled groundbreaking “soft valve” technology. This pioneering solution seamlessly integrates sensors and control valves while preserving complete softness.
Soft inflatable robots have emerged as a promising breakthrough for applications demanding safety and adaptability. However, integrating sensing and control systems without compromising their softness and capabilities has been a significant challenge.
Traditionally, soft robots coexisted with rigid electronic components for sensing purposes. This study introduces a novel approach, creating soft analogs of sensors and control valves that operate without electricity.
The resulting tube-shaped part performs dual functions: detecting external stimuli and precisely controlling motion solely using air pressure. By eliminating the need for electricity-dependent components, these all-soft valves enable safe operation in underwater environments and areas where sparks could pose risks. Additionally, each component is cost-effective at approximately 800 Won.
Professor Kim explained, “Previous soft robots had flexible bodies but relied on hard electronic parts for stimulus detection sensors and drive control units. Our study focuses on making both sensors and drive control parts using soft materials.”
The research team showcased various applications for this groundbreaking technology. They developed universal tongs capable of delicately handling fragile items like potato chips, preventing breakage caused by excessive force.
Moreover, they applied these all-soft components to create wearable elbow assist robots, reducing muscle strain from repetitive or strenuous arm movements. The elbow support automatically adjusts based on the arm’s angle, resulting in a 63% average decrease in exerted force.
The soft valve operates by utilizing airflow within a tube-shaped structure. When tension is applied, a helically wound thread inside compresses it, controlling air inflow and outflow. This accordion-like motion allows for precise and flexible movements without electrical power.
Furthermore, the research team demonstrated that by programming different structures or numbers of threads, they could accurately control airflow variations. This programmability allows customized adjustments, providing flexibility in response even under consistent external forces.
Professor Bae expressed excitement about this development, stating, “These newly developed components can be easily employed using material programming alone, eliminating electronic devices.”
This groundbreaking soft valve technology marks a significant leap toward fully soft, electronics-free robots capable of autonomous operation, enhancing safety and adaptability across various industries.
The project received support from organizations including Korea’s National Research Foundation (NRF), Korea Institute of Materials Science (KIMS), and Korea Evaluation Institute of Industrial Technology (KEIT).