Daily Archives: February 3, 2023

3-D Printed Skin Improves Dexterity

The healthcare industry has always had a longstanding relationship with soft robotics. Soft robots are increasingly making their presence felt by assisting physicians in surgical procedures and turning major surgeries into minimally invasive procedures. With more physicians using soft robots that can feel and respond to stimuli, they can be substantially more precise, thereby posing a vastly lower risk of damaging sensitive organs and soft tissues with the wrong amounts of pressure.

Soft robots are more responsive to various stimuli, making them substantially more delicate and refined grippers for machines. They allow researchers to pick up delicate specimens deep underwater, or make complicated repairs outside the ISS. It is essential to have robots with dexterous and easy-to-control extremities. Their pressure-sensitive grippers can detect if they are holding a soft squid or a tiny metal part. They can adjust their grip accordingly, thereby preventing dangerous and time-consuming mistakes.

However, while emulating the sense of touch, researchers have had limited success with tactile-sensing technology, especially when fine-tuning dexterity. This is now changing with researchers from the University of Bristol creating the bionic sense of touch. Researchers from the Department of Engineering Maths are using 3-D printed papillae mesh on the under-surface of a compliant skin.

Scientists, in an empirical study, have made substantial comparisons of the performance of a bionic fingertip against neural recordings made of the sense of human touch. Not only have they published their findings in a Journal of the Royal Society Interface, they have also described the creation of an artificial biometric tactile sensor, which they call the TechTip. Their creation can behave dynamically just like human skin does, and provide sensory responses. In simple words, the artificial fingertip mimics human nerve signals.

The robotic hand has a 3-D printed tactile fingertip on its finger. A black flexible 3-D printed skin covers the white rigid back of the fingertip. The construction is similar to the dermal-epidermal interface of the skin and is backed by a mesh consisting of dermal papillae and intermediate biometric ridges. The dermal papillae comprise markers tipping the inner pins.

Scientists constructed the papillae on advanced 3-D printers with the capability of mixing hard and soft materials to emulate effects and textures similar to human biology.

The scientists claim their work uncovers the complex internal structure of the human skin and recreates the human sense of touch. For them, this represents an exciting development in the field of soft robotics. They have been able to 3-D print an artificial tactile skin that can lead to robots that are more dexterous. They can also significantly improve the performance of prosthetic hands, providing them with an in-built sense of touch.

According to scientists at the University of Bristol, a 3-D printed tactile fingertip can produce signals from its artificial nerves. These signals are similar to the recordings from real tactile neurons. They claim human tactile nerves transfer signals from numerous mechanoreceptors or nerve endings. These indicate the shape and pressure of contact. In their work, the scientists claim to have tested their 3-D printed artificial fingertip, and they found the same ridged profiles and a startlingly close match to the recorded neural data.