'Cockroach' and 'inspiration' are two words that don't often go together.
But a new cockroach-inspired design for small robots could help boost the bugs' reputation. Among the potential uses for such robo-roaches are monitoring the environment and even aiding in search and rescue operations.
In a study published in the journal Bioinspiration & Biomimetics, researchers used high-speed cameras to study how cockroaches traversed an obstacle course composed of narrowly-spaced, grass-like vertical beams. They found that the cockroaches' round outer shell was critical to their ability to move through such obstacles, so they equipped the robots with a cockroach-like shell of their own. This design allowed the robots are able to scuttle their way through densely cluttered obstacles, a feat that few other robots are capable of.
"This is a terrestrial analogy of the streamlined shapes that reduce drag on birds, fish, airplanes and submarines as they move in fluids," lead study author Chen Li of the University of California, Berkeley told Tech Times. "We call this 'terradynamic' streamlining."
In robotics, the standard approach to navigating through obstacles is simply to avoid them. A combination of sensors and algorithms help many current robots successfully get around obstacles. But in a disaster area, for example, this strategy may not be feasible.
"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," Li said.
Without its shell, the rectangular, six-legged robot pictured below was terrible at traversing the dense, grass-like obstacles that the researchers set up. Most of the time, it ended up getting stuck.
But when the researchers placed a round, roach-like shell atop the rectangular robot, it performed much better.
"Using our animal inspiration, we added a thin, rounded exoskeletal shell to our robot," said Li. "This enabled the robot to roll--rather than turn left or right--and fit its thin body through gaps to traverse densely cluttered obstacles by rolling its body like the animal does to fit through the gaps."
Instead of relying on sensory feedback, the cockroach-inspired robots instead traverse the obstacles by way of mechanical feedback. When one of these shelled robots encounters a cluster of dense obstacles, the shape of shell helps to re-orient the robot.
Relying on mechanical rather than sensory feedback means that the robots can be built with minimal sensors and controls. The researchers hope to find similarly simple 'terradynamic' solutions for navigating other obstacles by exploring different types of terrain and animal shapes.
