These cockroach-like robots could be used for everything from monitoring fields to search and rescue missions.
Inspired by discoid cockroaches, researchers at UC Berkeley have created a robot that can use its body shape to slip through tight spaces using natural parkour moves. Equipped with the insect’s characteristic rounded shell, the running robot can successfully complete a grass-like obstacle course, without the need for additional sensors or motors.
The Berkeley team, led by postdoctoral researcher Chen Li, hopes that the robot will one day inspire the design of future terrestrial robots that can be used in any number of applications, ranging from search and rescue operations to monitoring the environment. While many terrestrial robots have been developed with the ability to avoid obstacles in the past, very few have ever actually traversed them.
“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,” Li explains. “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.”
Whereas many robots are able to work on flat surfaces with a few obstacles, in nature, cockroaches and other small animals often have to navigate environments cluttered with shrubs, leaf litter, tree trunks and fungi. So for their study, the researchers employed high-speed cameras to film the movement of the discoid cockroaches through an artificial course comprised of tall, grass-like beams with limited spacing. The cockroaches were fitted with three different artificial shells to observe how their movement was affected by various body shapes, including an oval cone, a flat oval and a flat rectangle.
When the cockroaches were left unmodified, the researchers discovered that, although they sometimes pushed through or climbed over the fake grass, they most frequently used a fast and effective natural parkour moves to slip by the obstacles. In these situations, the robotic insects rolled their body so that their thin sides could slide through the gaps and their legs could push off the beams to help them maneuver.
They found that with a flat oval and rectangular bodies, the robot could not often traverse the beams and frequently collided with the objects in its way, often becoming stuck. Conversely, when fitted with the cockroach-esque rounded shell, the six-legged were able to successfully get through the course using a similar roll maneuver to the cockroaches. This adaptive behavior came about with no change to the robot programming, showing that the behavior came from the shell alone.
Looking ahead, the researchers hope to follow up this discovery by searching for other shapes in nature that could enhance the robots’ ability to advance through difficult terrain.
“There may be other shapes besides the thin, rounded one that are good for other purposes, such as climbing up and over obstacles of other types. Our next steps will be to study a diversity of terrain and animal shapes to discover more terradynamic shapes, and even morphing shapes. These new concepts will enable terrestrial robots to go through various cluttered environments with minimal sensors and simple controls,” Li adds.
The first results of the robot’s performance were shared in IOP Publishing’s journal Bioinspiration & Biomimetics.