Cockroaches are one of the most polarizing insects on earth. On one hand, many people consider them to be disgusting, disease-carrying bugs that crawl in the shadows and feast on garbage, but others view them as nature's great survival experts that can even survive deadly nuclear radiation. However, a group of researchers at the University of California - Berkeley, have used cockroaches as their inspiration for a new type of micro-robot that could revolutionize the way we search for survivors after natural disasters and other tragic events. At first glance, the robot looks like a small scrap of paper lying on the floor, but upon closer inspection, one can see that the robot is much more than just thin paper, and actually features two very small “feet” that are attached to a larger flat body. Exiting one end of the robot is a pair of very thin wires that leads to a waveform generator.
(Image Courtesy: UC Berkeley)
The robots are made of a thin layer of polyvinylidene fluoride, a piezoelectric material that is then encapsulated in an elastic polymer material. A small plastic leg is affixed to the underside at the front. When an AC current is applied to the piezoelectric material, the whole robot recoils slightly and then flexes back to its original shape. When this is done at high frequency, the robot scurries forward in a very cockroach-like manner. This inchworm type motion is quite efficient, and is able to propel the little robot forward, up hills, and even through pipes and tunnels.
What makes these robots so special is their simple design that features no mechanical parts. This means they can be made very small and very thin, and thanks to their elastic polymer frame, they even recover well from essentially being crushed flat by a human foot. In fact, the small robot pictured above is able to withstand over 60-kilograms despite weighing less than 65-milligrams. That’s about one million times its own weight. They are even able to carry something small like a peanut that weighs 500-milligrams which is five times its own weight.
“Most of the robots at this particular small scale are very fragile. If you step on them, you pretty much destroy the robot,” said Liwei Lin, a professor of mechanical engineering at UC Berkeley and senior author of a new study that describes the robot. “We found that if we put weight on our robot, it still more or less functions.”
(Video Courtesy: UC Berkeley YouTube)
If that was not impressive enough, these little electronic cockroaches are able to run almost 20 of their body lengths per second, rivaling the speed of its fastest organic cockroach counterparts. UC Berkeley says that their researchers are now working on attaching a battery pack, and sensors to the robots which would allow them to access the small spaces between walls, under crawl spaces, and even through debris and rubble after natural disasters such as earthquakes and tornadoes.
That’s where the real benefit of these robots will come in handy. Imagine emergency response teams deploying hundreds of these little robotic cockroaches to search for survivors, detect gas leaks, or even to aide rescuers with surveying structural damage of large building collapses to determine if it's safe to enter them or not. Fire departments could even employ an army of these robotic bugs to survey the remains of structure fires for hot-spots that could cause flare-ups once emergency crews leave the scene.
Even more importantly, thousands of small robots like this could one day help clean up past nuclear accident sites or even work together to seal off reactors that might meltdown in the future. At the moment, these robots can carry five or six times their own weight, but as research continues, it’s not a stretch to think that future iterations may be able to carry twenty-five to fifty times its own weight. This would allow each robot to carry a tiny amount of concrete into a damaged reactor, and over several days, a robotic cockroach army could seal off the entire reactor trapping deadly radiation and allowing humans or larger robots to finish the job.
If you would like to read more about these small robots, and the research surrounding them, you can read the full study in the journal Science Robotics.
Co-authors of the paper include Justin K. Yim, Zhichun Shao, Mingjing Qi, Junwen Zhong, Zihao Luo, Ronald S. Fearing and Robert J. Full of UC Berkeley, Xiaojun Yan of Beihang University and Jiaming Liang, Min Zhang and Xiaohao Wang of Tsinghua University. This work is supported in part by the Berkeley Sensor and Actuator Center, an Industry-University Cooperation Research Center.
Source: Berkeley News