This tiny beetle-inspired robot does what human hands can’t

YOKOHAMA, Japan — A new microrobot is poised to transform operations in confined spaces that are currently inaccessible to humans. Developed by researchers at Yokohama National University in Japan, this third-generation robot—nicknamed HB-3—improves upon its predecessors by eliminating the need for external power sources or control systems. It represents a significant leap forward in robotics technology designed for precision tasks in isolated environments.

The study, published in Advanced Intelligent Systems, explains the design of this innovative creation nicknamed HB-3 (Holonomic Beetle-3). It is a self-contained, wireless mini-robot that can operate with incredible precision in spaces too small or dangerous for humans to access. Until now, engineers had to compromise: robots were either untethered and autonomous, had high-precision movement, or were suitable for extreme environments—but never all three. HB-3 is the first to integrate these capabilities.

Nature-inspired design

Inspired by the locomotion of rhinoceros beetles, this tiny mechanical marvel takes inspiration from beetles while incorporating advanced sensors, actuators, and computer vision. About the size of a small coffee mug (90 × 116 × 104 mm) and weighing just 515 grams, HB-3 is compact enough to go where bulky conventional equipment cannot. Everything needed for independent operation, such as a camera, computer, battery, manipulator, and control circuits, is built into its small frame. This compact design represents a 97.9% reduction in total volume compared to earlier models.

“We’ve been able to push the boundaries of miniaturization to create a truly autonomous, untethered device that can operate in tight, hazardous spaces,” says Ohmi Fuchiwaki, associate professor with the Faculty of Engineering at Yokohama National University, in a statement. “The HB-3 can not only handle complex tasks but also do so with unmatched precision.”

The robot moves using special materials called piezoelectric actuators that respond to electrical signals by changing shape ever so slightly, sometimes by just billionths of a meter. These tiny movements, coordinated in a pattern similar to how beetles walk, allow HB-3 to move precisely in three dimensions.

Power management represents another significant achievement. The HB-3 carries its own lithium polymer battery, providing enough energy for autonomous operation within a 1600 × 1600 mm area per charge. This untethered operation removes the constraints of previous cable-dependent systems, allowing the robot to navigate freely within confined spaces.

A tiny ‘Inspector Gadget’

The autonomous capabilities of the HB-3 represent a significant advancement over manually controlled microrobots. Using its integrated camera and machine learning algorithms, the robot can identify target objects, calculate optimal paths, and perform pick-and-place operations without human intervention. This self-sufficiency makes it ideal for deployment in environments where remote control might be difficult or impossible.

In tests, HB-3 showed remarkable accuracy, positioning objects correctly 87% of the time, making it certainly capable of electronics assembly.

To be sure, researchers used HB-3 to assemble an electronic circuit in a confined space where human hands couldn’t reach. The robot successfully mounted various components, including resistors, LEDs, and transistors. However, the soldering process was performed manually. After reflow soldering, the circuit worked perfectly, with its LEDs blinking in sequence.

For another test, they modified HB-3 to place tiny droplets, just hundreds of micrometers across, in precise patterns. This demonstrates how the robot could assist in chemical and biological experiments requiring exact liquid handling.

HB-3 fills a growing need across many fields, from lab research to medical procedures to electronics manufacturing, for precise handling of small objects in places humans can’t easily reach. This includes sealed environments like vacuum chambers, clean rooms, and biohazard containment areas.

Like a tiny “Inspector Gadget” of sorts, the robot can be equipped with different tools as needed like tweezers, probes, soldering tips, and screwdrivers, making it versatile enough to handle tasks from the meter scale down to the nanometer.

A true robot-of-all-trades

While the current prototype completed autonomous pick-and-place operations in approximately 426 seconds—about 2.4 times longer than previous models due to computational limitations of the onboard Raspberry Pi—the researchers have identified clear paths for improving speed in future iterations through more powerful onboard processing or optimized detection algorithms. They’re also working on adding side-view cameras to improve depth perception and vertical positioning.

The practical uses for a tiny, precise, autonomous robot are nearly endless. It could repair sensitive equipment without extensive disassembly, handle hazardous materials in labs without exposing humans to risk, or perform delicate adjustments in places too small for human hands.

By combining miniaturization, autonomy, precision, and wireless operation in one package, HB-3 tackles multiple engineering challenges at once. The principles demonstrated in this tiny machine—autonomous operation, precise manipulation, and adaptability to confined spaces—could eventually reshape how we approach everything from microsurgery to satellite repair.

By drawing inspiration from one of nature’s most capable insects, these researchers have shown that sometimes the best way forward is to look at what’s already working in the natural world, just at a different scale. Just as beetles have evolved over millions of years to navigate complex terrain with agility, the HB-3 represents an evolutionary leap in robotic design—one that may scuttle into previously inaccessible spaces, performing precise tasks beyond human reach while carrying all the intelligence and power it needs within its beetle-inspired frame.