3D Printed Robotic Hand Marks The Dawn of Human-Like Robotic Movement

A collaborative effort between ETH Zurich and Inkbit has led to the 3D printing of a robotic hand, which remarkably simulates human anatomy with bones, ligaments, and tendons. This innovation signals a new time where the stiffness and mechanical nature of robots are transformed into movements that closely mirror the fluidity and agility of the human body.

Bridging the Gap: Overcoming Robotic Limitations

Traditionally, robots, despite their advanced capabilities, have been hindered by their mechanical construction, lacking the natural movement of organic bodies. ETH Zurich’s professor of robotics, Robert Katzschmann, highlights this limitation, pointing out that robots’ artificial links and joints, made from materials like carbon fiber and metal tubes, restrict their flexibility.

This recent advancement is set to transform the robotics field. The team, employing an innovative 3D printing technique known as vision-controlled jetting (VCJ), successfully produced a robotic hand. This hand remarkably replicates the intricate internal structure found in a human hand. “Our robotic hand can be printed in one go, no assembly is needed,” Katzschmann explains, underscoring the efficiency and innovation of this approach.


Vision-Controlled Jetting: A Game-Changer in Robotics


The VCJ method is an iconic departure from conventional 3D printing methods, which typically use fast-curing polyacrylates. These materials, while durable, do not offer the flexibility or softness required for more human-like movement. VCJ, on the other hand, uses soft, slow-curing thiolene polymers, known for their excellent elastic properties and rapid return to original states after bending.

MIT professor Wojciech Matusik, a co-author of the study, describes the VCJ process: “A feedback mechanism compensates for irregularities when printing the next layer by calculating any necessary adjustments to the amount of material to be printed in real time and with pinpoint accuracy.”


The Human-Like Robotic Hand: A Marvel of Engineering


The team’s achievement is best exemplified by the robotic hand itself. It consists of 19 tendon-like structures, touch pads, and pressure sensors, enabling it to sense touch, grasp objects, and even halt finger movements upon contact. This design was informed by MRI data of a real human hand, ensuring its anatomical accuracy.


Beyond the Hand: Diverse Applications


The potential of VCJ extends beyond just the robotic hand. The team also successfully printed a robotic heart, a six-legged robot, and a metamaterial capable of absorbing vibrations. Katzschmann envisions a future where VCJ can produce scalable hybrid soft-rigid robots, surpassing the current limitations faced by both hard and soft robots.


Revolutionising the Robotics Industry


This technology carries far-reaching effects. It not only simplifies the manufacturing process by enabling the printing of a robot’s entire structure in a single session, but it also paves the way for new opportunities in terms of adaptability and practical use. “VCJ will eventually replace all contact-based inkjet printing methods,” Katzschmann predicts, highlighting the method’s potential to impact robotics, medical implants, and various other industries.

This is a new era for robotics. Soft robots, constructed from pliable materials, bring distinct benefits. They reduce the likelihood of causing harm when interacting with humans and are more adept at handling delicate objects. The ETH Zurich-Inkbit collaboration has proven that with the right technology, these soft robots can be produced more efficiently and effectively, unlocking new inventions beyond robotics.