A living organism is capable of self-healing, but it is not so easy to impart such qualities to a robot. ACS Nano Letters magazine reports.
Living tissue can heal itself of many injuries, but it is extremely difficult to impart similar powers to artificial systems such as robots. Now the engineers have succeeded. They developed small floating robots that heal themselves on the fly after being broken into two or three pieces using magnets. The researchers say that someday this strategy could be used to create more reliable devices for cleaning the environment.
Small robots can “float” in liquids and perform useful functions. It’s not just about cleaning up the environment, but also about delivering drugs and performing operations. While most of the experiments were done in a laboratory, these tiny machines will eventually be released into real, harsh environments where they can get damaged. Swimming robots are often made from brittle polymers or soft hydrogels. Such materials crack or tear easily.
The engineers created a fish-shaped swimmer with a conductive bottom layer that was 2 cm long (the approximate width of a human finger). The design provides for a rigid hydrophobic middle layer, and on top of the robots are covered with a layer of highly magnetized microparticles. The team added platinum to the robot’s tail. The metal reacts with hydrogen peroxide fuel to form oxygen bubbles. They set the robot in motion. When the scientists placed the swimmer in a petri dish filled with a weak solution of hydrogen peroxide, he moved along its edge. The researchers then cut the swimmer with a blade, but his tail continued to move until it approached the rest of the body. Self-healing occurred due to a strong magnetic interaction. The same thing happened when the swimmer was cut into three or more pieces.