The breakthrough lies less in the robotic hand than in the printable material from which it was made.
DAEJEON, SOUTH KOREA
Korean researchers have developed an elastic material that allows a 3D-printed robotic gripper to hold fragile objects such as eggs without damaging them while remaining strong enough to lift a one-kilogram water bottle. The study was conducted by teams from KAIST, the Korea Institute of Science and Technology and Seoul National University of Science and Technology.
The researchers addressed a persistent problem in additive manufacturing. Materials soft enough for flexible robots are frequently difficult to print, while resins that cure reliably can become too rigid or tear when stretched. The team used machine-learning models to examine relationships among viscosity, curing time, tensile strength and elasticity across different chemical formulations.
The resulting resin balances printability with extreme flexibility. Test samples stretched to more than six times their original length and recovered without tearing easily. The material also endured repeated cycles of tension and compression, suggesting it could remain functional after continual deformation rather than succeeding in only a single laboratory demonstration.
Researchers printed pneumatic actuators that bend when filled with pressurised air, creating movement similar to flexible fingers. Three actuators were combined into a soft gripper capable of handling eggs, glass bottles, an egg carton and a computer mouse. The same device lifted a full water bottle weighing one kilogram.
The prototype should not be confused with a complete humanlike robotic hand. It does not reproduce the independent joints, tactile perception or complex manipulation abilities of human fingers. Its achievement is demonstrating how one adaptable structure can distribute pressure across objects with different shapes and degrees of fragility.
The research, published in Nature Communications, could support future development of warehouse grippers, wearable devices, rehabilitation equipment and customised medical products. Those applications remain prospective and will require testing for durability, manufacturing cost, biocompatibility and performance outside controlled conditions. The broader advance is a method through which artificial intelligence can reduce experimental trial and error when designing specialised printable materials.
Hechos que no se doblan. / Facts that do not bend.