Scientists have modeled a little robot on one of nature's hardiest insects: the cockroach. The robot has actually been around for a while, but now it has received an upgrade – a streamlined shell, perfect for helping the bot scrabble through obstacles.
Streamlined engineering is something that can be found both in nature and technology. For example, dolphins are specially shaped to help them glide through ocean waters and airplanes are designed to slice through the air to decrease air resistance. This is known as terradynamic streamlining.
These examples may seem rather majestic in comparison to the discoid cockroach, Blaberus discoidalis, but even this tiny insect has a streamlined shell that helps it move around. One might expect that the cockroach, being so small, would be stumped by the most seemingly innocuous objects: grass, shrubs, dry leaves. But few animals trump this cockroach's use of body shape to traverse obstacles.
The roach uses its natural 'parkour skillz', side-rolling to get around barriers it comes across. It is this rotating motion that the team from the University of California, Berkeley, wanted to replicate in their cockroach-inspired robot.
Lead author of the study Chen Li, said: "The majority of robotics studies have been solving the problem of obstacles by avoiding them, which largely depends on using sensors to map out the environment and algorithms that plan a path to go around obstacles. However, when the terrain becomes densely cluttered, especially as gaps between obstacles become comparable or even smaller than robot size, this approach starts to run into problems as a clear path cannot be mapped."
Terradynamic streamlining inspired from cockroaches. Chen Li/University of California, Berkeley
The video first demonstrates how a cockroach rolls its body to the side to navigate a densely cluttered, grass-like obstacle. The next section of the video shows the original robot. As you can see, it's pretty useless at navigating beam obstacles. The team could have added sensors to help the VelociRoACH bot, but a much simpler solution was to design it an oval exoskeleton, seen in the third section of the video.
As described in Bioinspiration & Biomimetics, the team tested three different shell shapes on real cockroaches: an oval cone shape, a flat oval and a flat rectangle. The less rounded the shell, the harder it became for the cockroach to effectively roll onto its side to move through obstacles. The same result is shown in the video: The robot with a rectangular frame finds it near impossible to zoom through the fake grass.
Here, VelociRoAch uses the same tilting technique that the cockroach uses every day. While the technique might not be beautiful, it is effective, and as you can see, the upgraded robo-roach plows through the obstacle course intact, ready to crawl into your nightmares.