Less than one verminThe robot can walk, bend, turn, turn and jump.
Northwestern University engineers have developed the smallest remotely controlled walking robot ever – and it comes in the form of an adorable, tiny crab.
Just half a millimeter wide, the tiny crabs can bend, twist, slither, walk, spin and even jump. The researchers also developed millimeter-sized robots that resemble inchworms, crickets, and beetles. While the research is exploratory at this time, the researchers believe their technology could bring the field closer to the realization of microscopic robots that can perform Realistic missions inside confined space.
The Research has been published in the journal Science Robotics. Last September, same team Introducing a Winged Circuit it’s the smallest man-made flying structure ever (published on the cover of Nature).
Smaller than a flea, the tiny robot crab sits next to the eye of a sewing needle. Image credit: Northwestern University
“Robots are an exciting area of research and the development of microrobots is an exciting topic for academic exploration,” said John A. Rogers, who directed the experimental work. “You can imagine microrobots as agents that repair or assemble small structures or machines in industry or as surgical assistants to unclog blocked arteries, stop internal bleeding or remove cancerous tumors – all in minimally invasive procedures.”
“Our technology allows for multiple modes of movement to be controlled and it is possible to walk at an average speed of half your body length per second,” added. Yonggang Huang, who led the theoretical work. “This is a huge challenge to achieve on such a small scale for terrestrial robots.”
A pioneer in bioelectronics, Rogers is the Louis Simpson and Kimberly Querrey Professor of Materials Science and Engineering, Biomedical Engineering, and Neurosurgery at Northwestern’s McCormick School of Engineering and Feinberg School of Medicine and director of Querrey Simpson Institute of Bioelectronics (QSIB). Huang is the Jan and Marcia Achenbach Professor of Mechanical Engineering and Civil and Environmental Engineering at McCormick and a key member of the QSIB.
Smaller than fleas, crabs are not powered by complex hardware, hydraulics, or electricity. Instead, its strength lies in the body’s resilience. To build the robot, the researchers used a shape-memory alloy material that can transform into its “remembered” shape when heated. In this case, the researchers used a scanning laser beam to rapidly heat up the robot at various targeted locations on its body. A thin layer of elastic glass returns the corresponding part of the structure to its deformed shape on cooling.
As the robot changes from one stage to another – deforming into a memorized shape and back again – it creates motion. The laser is not only remotely controlled to activate the robot, but the scanning direction of the laser also determines the direction of the robot. For example, scanning from left to right will make the robot move from right to left.
“Because these structures are so small, the cooling rate is very fast,” explains Rogers. “In fact, reducing the size of these robots allows them to run faster.”
To create such a small creature, Rogers and Huang turned to a technique they introduced eight years ago – a pop-up assembly method inspired by a child’s pop-up book.
First, the team fabricated a precursor to the walking crab structure in a flat, flat geometry. They then bonded these precursors to a slightly stretched rubber sole. When the stretchy substrate is released, a controlled displacement process occurs that causes the crab to “pop” into precisely defined three-dimensional forms.
With this manufacturing method, the Northwestern team is able to develop robots of various shapes and sizes. So why a peekytoe crab? We can thank Rogers’ students and Huang for that.
“With these assembly techniques and material concepts, we can build a walking robot of almost any size or 3D shape,” says Rogers. “But the students got excited and enjoyed the sideways movement of the little crabs. It’s a creative whim. “
Source: WOMENorthwestern university
