A “brainless” robot that can navigate its way around complex mazes has been developed.
Researchers have shown the ability of the soft robot to navigate mazes with moving walls – and fit through spaces narrower than its body size.
They have tested the new robot design on both a metal surface and in sand with similar success.
Scientists say it rolls like a plastic cup, which is wider at the top than at its base.
The team at North Carolina State University previously created a soft robot that could navigate simple mazes without human or computer direction.
Now they have taken their work a major step forward by creating a “brainless” soft robot that can navigate more complex and dynamic environments.
Dr. Jie Yin said: “In our earlier work, we demonstrated that our soft robot was able to twist and turn its way through a very simple obstacle course,” says.
“However, it was unable to turn unless it encountered an obstacle.
“In practical terms, this meant that the robot could sometimes get stuck, bouncing back and forth between parallel obstacles.
“We’ve developed a new soft robot that is capable of turning on its own, allowing it to make its way through twisty mazes, even negotiating its way around moving obstacles.
“And it’s all done using physical intelligence, rather than being guided by a computer.”
He explained that “physical intelligence” refers to dynamic objects – such as soft robots – whose behavior is governed by their structural design and the materials they are made of, rather than being directed by a computer or human intervention.
As with the earlier version, the new soft robots are made of ribbon-like liquid crystal elastomers.
When the robots are placed on a surface that is at least 55 degrees Celsius (131 Fahrenheit), which is hotter than the ambient air, the portion of the ribbon touching the surface contracts, while the portion of the ribbon exposed to the air does not.
That induces a rolling motion; the warmer the surface, the faster the robot rolls.
While the previous version of the soft robot had a symmetrical design, the new robot has two distinct halves.
One half is shaped like a twisted ribbon that extends in a straight line, while the other is shaped like a more tightly twisted ribbon that also twists around itself like a spiral staircase.
The research team says that the asymmetrical design means that one end of the robot exerts more force on the ground than the other end.
Dr. Yin said: “Think of a plastic cup that has a mouth wider than its base.
“If you roll it across the table, it doesn’t roll in a straight line – it makes an arc as it travels across the table. That’s due to its asymmetrical shape.”
First author Dr. Yao Zhao, a postdoctoral researcher at NC State, said: “The concept behind our new robot is fairly simple: because of its asymmetrical design, it turns without having to come into contact with an object.
“So, while it still changes directions when it does come into contact with an object – allowing it to navigate mazes – it cannot get stuck between parallel objects.
“Instead, its ability to move in arcs allows it to essentially wiggle its way free.”
Dr. Yin added: “This work is another step forward in helping us develop innovative approaches to soft robot design – particularly for applications where soft robots would be able to harvest heat energy from their environment.”
The findings were published in the journal Science Advances.
Produced in association with SWNS Talker