A robot inspired by the shape and movement of a cockroach has been built to traverse densely cluttered environments without the need for additional sensors or motors.
Researchers at the University of California have discovered that when the robot was fitted with a rounded shell similar to that of a discoid cockroach, it could perform a roll manoeuvre inspired by the movement of the insect to get through gaps between grass-like vertical beams.
Previous terrestrial robotic studies have just focused on getting robots to avoid obstacles, but the researchers hope the results of this study could eventually be used in search and rescue operations as well as for monitoring the environment.
Chen Li, lead author of the study 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.”
The study involved high-speed cameras observing cockroaches moving through obstacles usually found in their natural environment, such as blades of grass, shrubs and leaf litter. The cockroaches were then fitted with three types of artificial shell – one similar to their own shell, a flat oval and a flat rectangle – and were again studied traversing the obstacles.
The results showed the cockroaches moved slower and were less able to successfully roll their bodies so they could fit between the obstacles than when they were unmodified. The researchers then fitted a cockroach-inspired rounded shell to their rectangular six-legged robot and found that with the shell fitted, it could move more easily through hurdles without any need to change its programming.
Li said: “We showed that our robot can traverse grass-like beam obstacles at high probability, without adding any sensory feedback or changes in motor control, thanks to the thin, rounded shell that allows the robot body to roll to reduce terrain resistance. This is a terrestrial analogy of the streamlined shapes that reduce drag on birds, fish, airplanes and submarines as they move in fluids. We call this ‘terradynamic’ streamlining.”
The researchers are now planning to test other shapes and other scenarios to discover if they assisted terrestrial robots can climb through or over obstacles in other environments.
You can read more about the developments in robotic technology in the latest issue of E&T magazine.