Imagine a future where doctors deploy thousands of microscopic robots to clear blocked arteries or deliver precise treatments. Researchers at Hanyang University have taken a major step toward this possibility by developing microrobots that can self-organize into swarms, tackle obstacles, and even transport heavy loads. In a groundbreaking study published in the journal Device, scientists demonstrated how these robots, each smaller than a grain of salt, can work together like an army of ants to solve complex problems.
Each of these miniature robots, measuring just 600 micrometers tall (about half a millimeter), is made using a process similar to ice cube molding, allowing researchers to create hundreds of these tiny robots cost-effectively. The robots are embedded with magnetic particles called neodymium-iron-boron (NdFeB), enabling them to respond to external magnetic fields and interact with one another. This allows them to form various shapes and structures to adapt to different challenges.
When exposed to a rotating magnetic field, the robots self-organize into three main formations: end-to-end like a train, overlapping like roof shingles, or face-to-face like magnets on a refrigerator. Unlike previous swarm robotics that used spherical robots connecting point-to-point, these cube-shaped robots create much stronger connections by allowing full faces to touch, mimicking how magnets form stronger bonds when their surfaces align.
One of the most impressive demonstrations involved a swarm of 1,000 robots that created a floating raft on the surface of water. This “robot raft” then successfully transported a pill that weighed 2,000 times more than the individual robots. The behavior of these robots mirrors the actions of fire ants, which create living rafts to survive floods—proving that engineers can often find inspiration for innovation in nature.
On land, the swarms demonstrated even more remarkable feats. Eight robots joined together to climb walls that were five times their height. In another experiment, the robots worked as a collective to clear blocked tubes, simulating how these robots might one day be used to clear clogged arteries in the human body. The robots even demonstrated the ability to transport objects up to 350 times their own weight, showcasing their strength and adaptability.
Beyond their ability to clear obstacles and transport objects, these robots also show a unique sensitivity toward living creatures. Researchers successfully used the robot swarms to guide ants and pill bugs along predetermined paths without causing any harm. Additionally, the robots created a feeding control system for larger organisms, like superworms, by controlling access to food in a strategic manner.
The key to controlling these robot swarms lies in the manipulation of magnetic fields. By rotating the magnetic fields around the robots, researchers can make them spin, move in circles, or change direction. The strength of the magnetic field allows the robots to switch between different movement styles, providing versatility in how they navigate various environments.
While these magnetic microrobots are a breakthrough, they still require external magnetic control and cannot autonomously navigate complex environments, like the narrow and confined spaces of human arteries. According to Jeong Jae Wie, a study author from Hanyang University, future research will focus on improving the autonomy of these microrobot swarms, enabling real-time feedback control of their motions and trajectories.
The potential applications for these tiny robots are vast. From medical procedures, such as clearing blocked arteries, to more advanced uses in environmental cleanup or even microscale manufacturing, these swarming robots could reshape numerous industries. As researchers continue to enhance their capabilities, it’s not hard to imagine a future where these robots become an essential tool in medicine, improving the precision and efficiency of treatments while reducing risks for patients.
The future of robotics is tiny, magnetic, and highly coordinated—marking the dawn of a new age in swarm technology.
By Impact Lab