Scientists build 'grain of salt' sized robot that can travel through human body
- By Kumail Shah -
- Dec 15, 2025
A collaborative research project between the University of Pennsylvania and the University of Michigan has achieved a breakthrough in robotics. They built a sub-millimeter robot equipped with an onboard computer, motor, and sensors. This microrobot is a major leap forward despite being smaller than a grain of salt and not yet the nanomachines of science fiction.
Described in the journal Science Robotics, the device is praised by scientists as the first tiny robot capable of sensing, thinking, and acting autonomously.
Previously, microscopic robots depended on external control, restricting their ability to process information and respond to their environment. This new robot overcomes that limitation. Scientists believe it potentially paves the way for future medical applications like tissue repair or targeted drug delivery.
“Every living thing is basically a giant composite of 100-micron robots,” co-author Marc Miskin from the University of Pennsylvania told the Washington Post, highlighting the biological relevance of this scale.
Visually resembling a microchip encased in glass to protect against fluids, the robot is constructed from silicon, platinum, and titanium. The device is powered by solar cells. It propels itself by using electrodes to create a flow within the surrounding water particles. This essentially enables it to swim.
Though its onboard computer is considered slow by modern standards, it is capable of sensing and reacting to environmental changes, such as shifts in temperature.
“At this scale, the robot’s size and power budget are comparable to many unicellular microorganisms,” the team noted in the study.
Interestingly, the robot can communicate with human operators via a laptop. “We can send messages down to it telling it what we want it to do. It can send messages back up to us to tell us what it saw and what it was doing,” Miskin explained. Scientists are working diligently on these innovations.
Co-author David Blaauw predicts real-world deployment of these microrobots within a decade, though the technology is still in the experimental phase and not yet ready for human use. The research team’s immediate focus is on achieving the next breakthrough. They aim to enable these microrobots to communicate with one another.