UT Austin researchers achieve complex human hand 3D print with single material
New 3D printing technique enables production of hand that mimics the nuanced “feel” of human flesh and bone
Researchers at the University of Texas at Austin have developed a 3D printing method that can create complex replicas – like human hands – with varying hardness, from a single material, and using inexpensive hardware.
The novel 3D printing technique, named CRAFT (Crystallinity Regulation in Additive Fabrication of Thermoplastics) can help to improve medical training and protective gear, and enables the production of objects on a pixel-by-pixel basis.
As part of its testing, the team successfully fabricated a model of a human hand that mimics mechanical characteristics such as skin, bones, ligaments, and tendons. It was printed using low-cost, commercially-available standard digital light processing (DLP) printer, and with a single feedstock.
The DLP printer enabled the transformation of cyclooctene, a liquid resin, into solid plastic, and achieved complexity through the variation of the intensity of light projected onto the resin. Traditional 3D printing techniques usually require different “inks” to achieve varying textures of finish.
“We can control molecular-level order in three-dimensional space, and in doing so, completely change the mechanical and optical properties of a material,” said Zak Page, a UT associate professor of chemistry. “And we can do that all from a really simple, inexpensive feedstock by just changing the light intensity. It’s the simplicity at the heart of it that’s really exciting.”
Through the application of high-intensity light CRAFT can produce rigid, bone-like structures and lower intensities can define flexible areas that more resemble flesh. For this reason, CRAFT’s application in medical training has exciting potential, and offers a more cost-effective, less ethically complex, and less resource dependent option than the traditional route: human cadavers.
Traditional 3D printed models used for similar purposes often fail to replicate lifelike surgical scenarios because multi-material prints do not bond as well and fail under stress.
