Researchers created a small swimming robot that can heal itself. This development could be used to make hardier devices for environmental and industrial clean-up.
Tiny robots are typically made of brittle polymers or soft hydrogels that crack or tear easily. The team wanted to design swimmers that could heal themselves in motion without human help or external triggers.
Source: ACS Nano Letters
The team’s swimmers were 2 cm long, about the width of a finger, and are shaped like a fish. The bottom layer is conductive with an upper strip of aligned, strongly magnetic microparticles. Platinum was added to the tail. Platinum reacts to hydrogen peroxide fuel to create propelling oxygen bubbles. These tiny robots can swim through fluids and carry out useful functions, like cleaning up an environment, delivering drugs and performing surgery.
To test the robot, the team placed it in a petri dish filled with a weak hydrogen peroxide solution. The robot moved around the dish while researchers cut it with a blade. The tail kept traveling until it approached the body and reformed the fish shape with strong magnetic interaction. The researchers found that the robots could heal themselves when cut into three pieces or when a magnetic strip was placed in different configurations. It was a versatile, fast and simple self-healing strategy.
Most of the experiments with these robots were done in the lab, but the team has plans to release the robots into harsh environments where the robots would naturally become damaged. This research is an important step toward on-the-fly repair for small-scale swimmers and robots.
This research was published in ACS Nano Letters.
