Inspired by the Japanese art of paper folding, researchers have developed soft yet strong robotic grippers capable of delicate and heavy-duty tasks alike. From folding clothes to grasping superthin microfibers, lifting 16,000 times its weight yet gently turning book pages, the versatile device has numerous potential applications from prosthetics to surgery and deep sea exploration.

Recently various gripper designs emerged, including electricity-free flower-inspired ones. However, North Carolina State University engineers may have taken robotic gripping to a new level.

“Designing a single soft gripper able to handle ultrasoft, ultrathin and heavy objects is challenging due to the trade-off between strength, precision and softness,” said co-author Jie Yin. “Our origami-inspired design achieves an excellent balance of these characteristics.”

To be useful in diverse situations, an ideal gripper needs delicate and dexterous capabilities alongside raw power. The researchers realized these attributes relate more to gripper geometry than composition. To achieve their goal, they turned to origami.

In origami, 2D paper is folded and cut into 3D shapes. Adapting techniques from this art form lent the grippers unique advantages.

As Yin explained, “The power of robotic grippers is usually measured by the payload-to-weight ratio. Our grippers weigh 0.4 grams and can lift up to 6.4 kilograms. That's a payload-to-weight ratio of around 16,000. This is 2.5 times higher than the previous record of 6,400.”

Lead author Yao Hong said, “Combined with softness and precision, the high strength enables broad utility.”

Practically, the strength allows constructing grippers from biodegradable materials like tough plant leaves for limited time tasks involving food or biomaterials. Potential applications include handling sharp medical waste such as needles.

In trials, the researchers integrated their grippers with a prosthetic hand, successfully turning pages and picking grapes off vines. The results suggest precise delicate manipulation is an ideal focus for advancing robotic gripping further.

“This gripper allows tasks difficult for current prosthetics, like fastening certain zippers, picking up coins, etc.,” said co-author Helen Huang. “While not replacing all prosthetic hand functions, it can be a useful add-on. And origami grippers don't require replacing or modifying existing robotic prosthetic motors.”

According to the researchers, their novel grippers could have far wider uses still, from minimally invasive surgeries, handling ultrafine materials, to high pressure underwater gripping for deep sea exploration.

By emulating the art of paper folding, the engineers created grippers with a highly optimized balance of softness, precision and unprecedented power. Their origami-based approach could redefine the potential of robotic grasping.