Soft robots are known for their ability to bend, stretch, and adapt to their surroundings. However, most of them still need rigid electronic components for control and timing, which limits their flexibility.
Researchers at Georgia Tech are changing that with a groundbreaking invention: self-regulating soft electromagnetic oscillators.
These unique soft actuators can move and perform tasks using only a battery—no bulky microcontrollers, pumps, or logic circuits are required.
This innovation was led by Noah Kohls, Ph.D. ME 2024, and assistant professor Ellen Yi Chen Mazumdar from the George W.
Woodruff School of Mechanical Engineering. Their study was recently published on the cover of Advanced Materials Technologies.
Kohls explained that the goal was to create a fully self-contained soft system capable of realistic tasks without relying on heavy electronic components.
By embedding control directly into the structure of the robot, the team managed to reduce the need for rigid electronics. This breakthrough allows the soft robots to move with greater fluidity and flexibility, opening the door to many new applications.
The inspiration for this technology came from nature, specifically the way earthworms move through peristaltic motion. Earthworms contract and relax their muscles in waves to push their bodies forward. Drawing from this concept, the team developed soft linear and rotary actuators that can perform complex movements.
These actuators are made from silicone structures combined with custom-compliant magnets and liquid metal conductors. Despite their softness, these components are powerful enough to drive a small robotic car, run a fan, pump liquids, and even move underwater—all while remaining flexible and easy to reshape.
What sets these soft electromagnetic oscillators apart is their ability to produce rhythmic motion without the need for traditional control systems.
Much like a clock regulates time, these oscillators create steady, timed movements that allow the robots to crawl, hop, or swim with just a low-voltage power source of 5 to 20 volts.
They can also achieve movement frequencies of 20 to 40 hertz, which is faster than many existing soft actuators. This makes them ideal for navigating tight or unpredictable spaces, such as inside the human body.
Kohls shared that his fascination with robotics began during his undergraduate studies, where he built a custom robot for his family’s plant nursery. The robot was designed to help plant more than 10,000 cuttings each spring, reducing the physical workload.
That project inspired him to explore how robotics could simplify everyday tasks and improve lives. With the development of these self-regulating soft oscillators, Kohls and his team are bringing that vision to life, one flexible robot at a time.
