New nanobots that ‘fly’ through the body could perform tiny surgeries

6 Nov 2019

From left: Laura Heyderman and Tian-Yun Huang look at a model of the origami bird, while Jizhai Cui observes the real nanorobot under a microscope. Image: PSI/Mahir Dzambegovic

Researchers have developed nanobots that could perform small operations in the body and move around by flapping their wings.

The Japanese art of origami has inspired many robotic designs, but researchers from the Paul Scherrer Institute (PSI) and ETH Zurich have revealed new bird-like nanobots that could make a big difference to healthcare.

Writing in Nature, the researchers said these micromachines – measuring just a few nanometres across – can perform a number of different actions. The design is similar to an origami bird but, unlike a paper structure, this robot moves thanks to nanomagnets controlled by magnetic fields.

When it wants to move, the nanobot flaps its wings or bends its neck and retracts its head. Crucial to this movement are nanomagnets that can be programmed to assume a particular magnetic orientation. If these magnets are located in flexible components, the forces acting on them cause the components to move.

A matter of milliseconds

Crucially, the nanomagnets can be programmed again and again, allowing the robot to take on a number of movements. In doing so, these nanobots could be programmed to perform small operations in the human body. To construct it, the researchers fabricated arrays of cobalt magnets on thin sheets of silicon nitride.

“The movements performed by the microrobot take place within milliseconds,” said Laura Heyderman of ETH Zurich.

“But programming of the nanomagnets only takes a few nanoseconds. This makes it possible to program the different movements one after the other. This means that the tiny microbird can first flap its wings, then slip to the side and afterwards flap again. If needed, the bird could also hover in between.”

Explaining its potential in healthcare, Heyderman’s colleague, Bradley Nelson, said: “It is conceivable that, in the future, an autonomous micromachine will navigate through human blood vessels and perform biomedical tasks such as killing cancer cells.”

Other potential applications, the researchers said, include flexible microelectronics or microlenses that change their optical properties.

Colm Gorey was a senior journalist with Silicon Republic