A team of engineers at the University of New South Wales in Sydney, Australia, has developed a tiny, flexible robotic arm that's designed to 3D print material directly on the surface of organs inside a living person's body. "Our flexible 3D bioprinter means biomaterials can be directly delivered into the target tissue or organs with a minimally invasive approach," he added. "This system offers the potential for the precise reconstruction of three-dimensional wounds inside the body, such as gastric wall injuries or damage and disease inside the colon." It's not the first in-vivo 3D printer ever to be created. In 2020, for instance, a group of Chinese researchers developed a microrobot that can be used to patch stomach ulcers. https://futurism.com/neoscope/scientists-3d-print-inside-human-body