Reviewed by Lexie CornerFeb 25 2025
Ebru Demir, a researcher, has received an NSF CAREER Award to study the movement of groups of AI-driven microswimmers in biological fluids, with potential applications in fertility treatments, medication delivery, and other areas.
Smart artificial microswimmers are small robots that mimic the behavior of bacteria or human sperm. They could be used in fertility treatments, minimally invasive surgery, and targeted drug delivery.
A single microswimmer cannot perform these tasks alone. Multiple swimmers will be needed, but it remains unclear how these groups will navigate the complex chemical and mechanical environment of bodily fluids.
We know that whenever a swimmer has a neighbor, it swims differently. Birds fly in a V formation because it’s more efficient and it saves them energy. But for a group of microswimmers, we don’t know what the best formation looks like.
Ebru Demir, Assistant Professor, Mechanical Engineering and Mechanics, P.C. Rossin College of Engineering and Applied Science, Lehigh University
Demir's research on developing Smart Artificial Microswimmers (SAMs) by combining artificial microswimmers with machine learning was recently funded by the National Science Foundation's Faculty Early Career Development (CAREER) Program. Her project aims to uncover the fundamental physics governing the movement of robotic swimmers in complex fluid environments by integrating AI into centimeter-scale swimmers and comparing their behavior with simulation predictions.
The NSF CAREER award is granted annually to junior faculty members across the United States who demonstrate excellence in research, teaching, and the integration of both. The award provides approximately $500,000 in funding over five years.
Demir plans to integrate microcontrollers running reinforcement learning algorithms into 3D-printed autonomous robots, ranging from 10 to 20 cm (4 to 8 inches) in size, to study their movements in both Newtonian and non-Newtonian fluids. Since blood and other bodily fluids have non-Newtonian properties, the viscosity of these fluids changes depending on the stress applied by the swimming body. To validate her simulation results, Demir will create fluids with similar characteristics for experimental use.
These swimmers will each contain an AI brain that will give them decision-making capabilities, so they can determine for themselves how to swim better alone, and how to swim better with three or five or 10 companions. It will also be interesting to see if their behavior changes if they are allowed to cooperate and share information.
Ebru Demir, Assistant Professor, Mechanical Engineering and Mechanics, P.C. Rossin College of Engineering and Applied Science, Lehigh University
For example, Demir explains that a swimmer might approach its partner and mistakenly believe it is moving faster than it actually is, causing it to get closer. Suddenly, it slows down and decides to return to the distance where it was moving most efficiently.
“As the SAMs swim, they are constantly interacting with the environment, running that algorithm, and recalculating where they are in that formation and how fast or how efficiently they are moving. The goal is to find the best strategy for the cluster to swim together in a manner that’s both fast and efficient,” said Demir.
The ultimate goal is to introduce artificial swimmers, either micron-sized or centimeter-sized for use in larger vessels like those in the gastrointestinal tract, into the body. These swimmers could travel through veins to deliver specific chemotherapy medications or break up blood clots without the need for blood thinning. They might also assist in fertility treatments by guiding otherwise healthy, high-quality sperm.
“In those cases, the sperm has good genetics, but maybe its tail is compromised, and so the swimmers could push the sperm toward the egg. And that has been demonstrated by other researchers to work in a lab environment,” said Demir.
Demir says receiving the CAREER award and gaining recognition from her peers has been rewarding. However, what truly motivates her is the belief that her time in the lab could lead to solutions for life-changing problems.
As cliche as it sounds, I want to use engineering to help humanity.
Ebru Demir, Assistant Professor, Mechanical Engineering and Mechanics, P.C. Rossin College of Engineering and Applied Science, Lehigh University