Robots are becoming increasingly capable of performing complex tasks, from handling delicate objects to navigating challenging environments. However, developing robots that can interact safely and effectively with their surroundings requires more than advanced sensors and artificial intelligence. The materials used to build them are equally important. Recent developments in robotics highlight how polyurethane (PU), particularly thermoplastic polyurethane (TPU), is contributing to innovations in robotic hands, artificial skin and bio-inspired machines.
One example comes from the University of California, Irvine, where researchers have developed a 3D-printed robotic hand combining rigid finger segments with flexible TPU joints. This combination provides structural stability while allowing the fingers to adapt when interacting with objects. During testing, the hand successfully manipulated delicate items, including an egg and a raspberry, demonstrating how flexible materials can support more precise and adaptable robotic movements.
Similar benefits are being explored in agriculture. Researchers at West Virginia University have developed a soft robotic gripper designed to handle delicate fruit such as strawberries and avocados. Its fingers, made from silicone and polyurethane, allow it to grasp produce gently, while integrated sensors provide information about characteristics such as size, shape and ripeness. The technology could contribute to agricultural automation by enabling robots to handle delicate produce with greater care.
Polyurethane is also being investigated in technologies intended to give robots a sense of touch. Researchers at the University of Science and Technology of China have developed flexible electronic skin capable of detecting pressure, force direction and temperature changes. The technology incorporates a polyurethane film that serves as a flexible substrate and protective layer, contributing to durability and resistance to wear. Such developments could support future humanoid robots in detecting and responding to physical contact.
Beyond robotic hands and sensing technologies, TPU is also helping researchers explore new forms of movement. In Portugal, researchers at the Instituto Superior de Engenharia de Lisboa have designed a 3D-printed robotic fish inspired by natural swimming movements. Its flexible TPU structure and tail are designed to mimic the movement of real fish, demonstrating how adaptable materials can support bio-inspired robotics.
Meanwhile, a study published in Nature Communications demonstrated a four-legged robot manufactured using TPU materials with different levels of hardness. By combining flexible joints with more rigid structural components, researchers developed a robot capable of navigating different terrains, including sand, soil and rocky surfaces.
Together, these developments highlight the versatility of polyurethane in robotics. From flexible joints and soft gripping surfaces to artificial skin and bio-inspired structures, polyurethane-based materials offer opportunities to improve how robots move, sense and interact with their surroundings.
While many of these technologies remain at the research stage, they demonstrate how polyurethane could contribute to the development of increasingly adaptable, resilient and capable robotic systems.
