3D printing technology has taken another step with the creation of the first soft robotic handwith their bones, ligaments and tendonsthanks to the adaptation of this type of printers so that they can work with elastic plastics.

The discovery, published this Wednesday in the journal Nature, is a collaborative work of the Polytechnic University of Zurich (ETH) and the technology company Inkbit, a leading emerging company in 3D printing created by researchers from the Massachusetts Institute of Technology (MIT).

Until now, 3D printing was limited to the so-called fast-curing plastics (polymers)of great hardness, but now scientists have achieved the technological adaptation of these printers to slow-curing plastics, much more elastic, durable and robust.

Thanks to this adaptation, researchers They will be able to 3D print complex and more durable robots from various high-quality materials in one go.

This new technology can, therefore, now combine soft, elastic and rigid materials to create delicate structures and parts with all types of cavities at will, which will offer enormous possibilities for the development of soft robotics. This is the case of the achieved hand, which has bones, ligaments and tendons made of different polymers at once.

“With the fast-curing polymers that we have been using in 3D printing until now we would not have been able to make this hand, but thanks to the use of slow-curing polymers, which have great elastic properties and return to their original state much faster after bending than the others, we have made it possible,” said Thomas Buchner, professor of robotics at ETH Zurich.

The researcher has stressed that “robots made of elastic materials, like the developed hand, have multiple advantages on conventional robots made of metal, from having less risk of injury when working with humans to being more suitable for handling fragile goods.

To accommodate the use of slow-curing polymers, researchers have further developed 3D printing by adding a 3D laser scanner that immediately checks each printed layer for any surface irregularities. Instead of smoothing out uneven layers, the new technology simply takes the irregularities into account when printing the next layer.

“A feedback mechanism compensates for these irregularities when printing the next layer by calculating the necessary adjustments in the amount of material to be printed in real time and with millimeter precision,” said another of the authors, Wojciech Matusik, professor of Engineering. Electrical and Computer Science at MIT.

ETH Zurich has indicated in a statement that it will use the technology to design even more sophisticated structures and develop additional applicationswhile Inkbit will market it in new 3D printers.