CUHK engineers have invented a robot great for minimally invasive surgery and more. Its look is far from appealing, but it doesn’t have to be.

Nothing like your typical, stylish bot from sci-fi, this tiny, magnetically driven, shapeshifting robot was invented by a team comprising engineers from the Department of Mechanical and Automation Engineering. It represents a major improvement on existing robots of its type.

Robots like this had been around to allow non-invasive access to confined spaces and make tasks like minimally invasive surgery and targeted drug delivery possible. The problem with previously existing solutions, however, is that they either are not deformable enough to travel through highly confined spaces or must exist in a very specific solution to maintain its shape.

With this robot, the research team has hit the sweet spot. Made by adding neodymium particles coated with silica and borax into polyvinyl alcohol, it is both reconfigurable and adaptable. Tests have shown that it can move through channels as narrow as 1.5 mm wide and manoeuvre in different environments.

While neodymium is toxic in itself, the silica coating makes it safe to cells. This opens up such possibilities for biomedical application as retrieving button batteries swallowed by kids. Thanks to its ability to conduct electricity and perform such moves as curling and healing on its own upon being severed, it can also be used to repair circuits. And with an electrical resistance that changes according to the angle at which it bends, it can be attached to our body to monitor its motion.

The invention has been published in Advanced Functional Materials.