Researchers in South Korea have created swarms of minuscule, magnetically controlled robots that operate in tandem, mimicking the collective capabilities of ants to accomplish monumental tasks, including navigating and retrieving objects several times larger than themselves.
The research, published on Wednesday, December 18 by the Cell Press journal, suggests that microrobot swarms operating beneath a rotating magnetic field could be employed to tackle challenging tasks in harsh environments that individual robots would struggle to overcome, such as providing minimally invasive treatment for clogged arteries and precisely guiding organisms.
“‘The microrobot swarms’ unprecedented ability to seamlessly adapt to their surroundings and exercise autonomous control has left us astonished,’ remarks Dr. Jeong Jae Wie, a leading researcher at Hanyang University’s Division of Natural and Nano Engineering in Seoul, South Korea.”
Researchers investigated the efficacy of microrobot swarms comprising diverse configuration settings in executing a broad spectrum of tasks. Researchers found that densely packed swarms of micro-robots can collectively overcome obstacles five times their individual size by working together, with each robot successively surmounting barriers in a coordinated effort.
Researchers successfully assembled a massive swarm of 1,000 microrobots with exceptional packing density, forming a buoyant raft that floated on water and encircled a capsule weighing approximately 2,000 times more than each individual robot, thereby enabling the swarm to transport drugs through the liquid.
On solid ground, a robotic swarm successfully transported cargo weighing 350 times more than the average individual, while another micro-robot swarm demonstrated its ability to clear blockages resembling clogged blood vessels. By leveraging spinning and orbital dragging motions, Wie’s team successfully created a system capable of tracking the movements of small organisms through robotic swarms’ information transmission.
Researchers are increasingly fascinated by the potential for swarms of robots to collaborate and achieve common objectives, inspired by the remarkable social behavior of ants, who work together to traverse obstacles or form rafts to survive floods. As robotic systems operate in concert, they exhibit increased resilience to failure – even if individual components falter or fail to meet expectations, the collective continues functioning through programmed actions until a critical mass achieves success.
According to Wie, earlier research in swarm robotics has primarily focused on the collective behavior of spherical robots that aggregate through point-to-point contact. The investigators engineered a swarm consisting of cube-shaped micromachines, unified by a robust magnetic attraction.
Given the larger floor areas, a higher number of dice faces can potentially interact with each other.
Each microrobot measures 600 micrometers in height, comprising an epoxy-based physique reinforced with particles of ferromagnetic neodymium-iron-boron (NdFeB) that enables it to respond to magnetic fields and collaborate with other microrobots. The swarm of robots is able to self-assemble when powered by a magnetic field generated through the rotation of two coupled magnets. Researchers designed multiple robot configurations by manipulating the magnetic orientation of each robot across varying angles.
“When asked about their breakthrough, Wie explains, ‘We’ve successfully developed an economical mass manufacturing method that combines onsite reproduction molding with magnetization, ensuring consistent uniformity in both geometry and magnetization profiles to guarantee maximum efficiency.'”
“While the research’s findings show great potential, experts warn that autonomous systems need more freedom and independence before being ready for practical applications.”
“While magnetic microrobot swarms do have the potential to revolutionize medical procedures, they currently rely on exterior magnetic control and are limited in their ability to autonomously navigate complex or confined spaces, such as actual arteries.” Future studies will focus on increasing the autonomy of microrobot swarms by implementing real-time trajectory optimization and motion planning to enhance their decision-making capabilities.
