Inkbit’s Vision Controlled Jetting (VCJ) 3D printing technology has been used to produce a robotic hand with bones, ligaments and tendons made of different polymers.

This robotic hand is a tendon-driven hand modelled from MRI data and was produced by researchers at ETH Zurich’s Soft Robotics Lab, alongside researchers at MIT, to demonstrate how VCJ technology could fabricate complex, multi-functional systems in a single print without the need to assemble subcomponents. The researchers also printed a pneumatically actuated walking manipulator, a pump mimicking a heart and novel metamaterial structures.

Inkbit’s technology is able to print intricate, multi-material parts in a wide range of mechanical properties thanks to a closed-loop feedback control operation that eliminates the need for mechanical planarizers and enables the processing of slow-cure chemistries. These slow-cure chemistries are said to be able to build the polymer chain more precisely and deliver more durable and robust properties. They also help to facilitate very good elastic properties, according to the researchers, which see the slow curing thiolene polymers return to their original state much faster after bending than polyacrylates.

“With Inkbit’s VJC technology and materials, for the first time, we were able to print something as complex as a robotic hand with bones, ligaments and tendons, mirroring a fully functioning human hand, and do so in one go,” commented Thomas Buchner, doctoral student at ETH Zurich. “Inkbit’s TEPU material has very good elastic properties and bounce back to their original state much faster after bending than polyacrylates, making it ideal for producing the robotic hand’s elastic ligaments.”

“Our VCJ technology is a qualitative change in the field of additive manufacturing,” added Davide Marini, CEO, Inkbit. “We are closing the gap between the elegantly sophisticated structures we admire in nature and our ability to replicate them synthetically. This isn’t just a step forward; it’s a leap into a new era of manufacturing.”

With VCJ, the researchers found that the technology enhances the resolution and functional capabilities of printed components, while also enabling the fabrication of intricate internal networks of channels and cavities to carry signals, power or fluids through the structure. These printing and materials capabilities have been underpinned by Inkbit’s AI-enabled 3D computer vision scanning system that captures the print geometry of each layer in real time.

“A feedback mechanism compensates for these irregularities when printing the next layer by calculating any necessary adjustments to the amount of material to be printed in a real time and with pinpoint accuracy,” offered Wojciech Matusik, a Professor at the Massachusetts Institute of Technology, who collaborated with Inkbit and ETH Zurich for this study.

A paper titled “Vision-Controlled Jetting for Composite Systems and Robotics” was published in Nature.