Living tissue can heal itself from numerous accidents, but offering similar talents to artificial techniques, this kind of as robots, has been particularly demanding.

Now, scientists reporting in ACS’ Nano Letters have designed smaller, swimming robots that can magnetically heal on their own on-the-fly after breaking into two or three pieces. The approach could someday be employed to make hardier gadgets for an environmental or industrial clear up, the scientists say.

Scientists have designed smaller robots that can “swim” through fluids and carry out helpful functions, this kind of as cleansing up the ecosystem, delivering drugs and performing operation. While most experiments have been completed in the lab, ultimately these little machines would be produced into severe environments, where by they could come to be destroyed.

Swimming robots are frequently produced of brittle polymers or soft hydrogels, which can quickly crack or tear. Joseph Wang and colleagues needed to structure swimmers that could heal on their own while in motion, without aid from people or other external triggers.

Microscopic swimmer robot. Picture credit: ACS (a even now from YouTube movie)

The scientists produced swimmers that were being 2 cm extended (about the width of a human finger) in the form of a fish that contained a conductive bottom layer a rigid, hydrophobic center layer and an upper strip of aligned, strongly magnetic microparticles.

The workforce additional platinum to the tail, which reacted with hydrogen peroxide gas to sort oxygen bubbles that propelled the robot. When the scientists placed a swimmer in a petri dish crammed with a weak hydrogen peroxide alternative, it moved around the edge of the dish. Then, they lower the swimmer with a blade, and the tail held travelling around until eventually it approached the relaxation of the entire body, reforming the fish form through a potent magnetic conversation.

The robots could also heal on their own when lower into three pieces, or when the magnetic strip was placed in distinct configurations. The multipurpose, speedy and straightforward self-healing approach could be an critical move towards on-the-fly repair service for smaller-scale swimmers and robots, the scientists say.