Scientists have created a magnetically-manipulated slime robot that could reduce the invasiveness of some surgeries

Scientists at the Chinese University of Hong Kong have created a magnetic slime robot. It can carry out tasks like fixing broken circuits and picking up objects. They also think one day it could be put inside the human body to do things like finding items that have been swallowed by accident. 

The slime robot can move around controlled by magnets, surround things in the shape of a C or O and pick them up, and can even interconnect electrodes.  "The ultimate goal is to deploy it like a robot," Zhang told The Guardian. "We still consider it as fundamental research trying to understand its material properties."

The slime robot is made from a blend of polyvinyl alcohol (a polymer), borax, and neodymium magnet particles. The result is a non-Newtonian fluid that behaves like a liquid or solid depending on force and can be controlled using external magnets. There is no robotics inside the slime at present, but you can steer it like a robot and the "ultimate goal" is to use it like one, according to researcher and co-creator Li Zhang.  

While the team has no immediate plans to test it in a medical setting, the scientists envisage the slime could be useful in the digestive system, for example in reducing the harm from a small swallowed battery. "To avoid toxic electrolytes leaking out, we can maybe use this kind of slime robot to do an encapsulation, to form some kind of inert coating," Chang said.

Magnetic miniature soft-bodied robots allow non-invasive access to restricted spaces and provide ideal solutions for minimally invasive surgery, micromanipulation, and targeted drug delivery. However, the existing elastomer-based (silicone) and fluid-based (ferrofluid or liquid metal) magnetically actuated miniature soft robots have limitations. In the study, non-Newtonian fluid-based magnetically actuated slime robots with both the adaptability of elastomer-based robots and reconfigurable significant deformation capabilities of fluid-based robots are demonstrated. The robots can negotiate through narrow channels with a diameter of 1.5 mm and maneuver on multiple substrates in complex environments. The proposed slime robot implements various functions, including grasping solid objects, swallowing and transporting harmful things, human motion monitoring, and circuit switching and repair.