Ultra-thin multimodal soft robots can explore narrow spaces for inspection and maintenance

Researchers from the University of Nottingham’s Rolls-Royce University Technology Centre (UTC) in Manufacturing and Embedded Technology have developed ultra-thin soft robots designed to explore tight spaces in challenging built environments. The research is published in the journal Nature Communications.

These advanced robots, with multimodal locomotion capabilities, are set to transform the way industries such as power plants, bridges and aircraft engines perform inspections and maintenance.

The innovative robots, known as Thin Soft Robots (TS-Robots), are just 1.7 mm thick, allowing them to access and navigate confined spaces, such as gaps just a few millimeters wide under doors or inside complex machinery.

TS robots feature a unique sandwich structure driven by dielectric elastomers, allowing them to crawl, climb, swim, and transition from solid to liquid domains. This adaptability makes them ideal for complex environments that include multiple obstacles on diverse terrains.

Dr Xin Dong, the project’s principal investigator who initiated the idea, said: “Our TS-Robots are designed to address the scientific challenges of multimodal locomotion in soft robotics, especially when they encounter obstacles such as narrow spaces, trenches, walls and liquids along their navigation paths.

“Unlike conventional robots, which face significant limitations in these environments, our technology offers a potential breakthrough for exploring difficult and complex terrain.”

Thin Soft robots notably exhibit exceptional performance in terms of force output and speed, achieving forces of up to 41 times their weight and speeds of 1.16 times their body length per second.

This exceptional capability allows them to collaborate with multiple TS-Robots or even other robots, such as drones, thus improving their functionality in tasks such as inspecting harsh environments or delivering goods.

Preliminary tests have already demonstrated the potential of Thin Soft Robots in real-world applications, including the inspection of electrical generators in advanced hybrid power systems. In this application, the robots were able to navigate the narrow air gap between the rotor and stator of a generator, a feat that traditional tools and robots cannot achieve.

“Starting from a ‘crazy’ idea conceived three years ago, I am pleased that we have not only proven an entirely new concept of soft robots, but also successfully found their application in real life,” said Dr Xi Wang, UTC Rolls-Royce researcher in manufacturing and wing technology.

Professor Dragos Axinte, Director of Manufacturing and Embedded Technologies at UTC Rolls-Royce, added: “The next generation of clean energy systems presents new challenges for inspection and maintenance. We are excited to see these flexible, slim robots offer the opportunity to address these challenges and contribute to the net-zero future.”

With these promising results, the research team plans to further optimize the robot design and explore new applications in sectors such as aerospace and energy maintenance and nuclear decommissioning.