Researchers at North Carolina State University have designed a “brainless” soft robot that can independently navigate through complex environments using a concept called physical intelligence. The new development comes at a time where the field of robotics is expanding rapidly, and is proving to be a critical jump in the soft robotics field.
The concept of the ‘brainless’ robot is not new. The researchers had previously built a soft robot model that could turn and move on its own. However, there was one caveat: the robot was not able to spontaneously change direction, it needed to physically encounter the obstacle in order to change its movement. In the newest version, the robot can turn and move on its own.
How does it do this? The main contributors are physical intelligence and the temperature of the robot’s environment.
Physical intelligence refers to objects, like a soft robot, whose behavior is determined by its structural design and the materials it is made of. Due to the unique build and asymmetrical design of the robot, the machine can move without being directed by a computer or human intervention. This is due to the new asymmetrical design, something that the older robot models did not have. One half of the robot exerts more force onto the ground than the other, which allows it to move in arcs, travels through complex obstacle courses, and avoid getting stuck between multiple objects. “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” says Professor Yin, an associate professor of mechanical and aerospace engineering at NC State University. The addition of the asymmetrical design in the new robot as compared to the symmetric design in the older model is what researchers found to be the reason that the robot could now move more independently through various mazes.
While researchers did alter the structure and design of the robot, the soft robots are still made with the same material as the older robot models. Liquid crystal elastomers, a polymer having elastic properties similar to rubber, are made from long molecular chains, linked in a way that makes them flexible but with some of the properties of liquid crystals. When the robot is placed on a surface that is at least 131 degrees Fahrenheit, the elastomers of the robot contract, causing a rolling movement. Researchers found that, the warmer the surface, the faster the robot moved.
“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,” says Yao Zhao, first author of the paper and a postdoctoral researcher at NC State. “So, while it still changes directions when it does come into contact with an object—allowing it to navigate a maze—it cannot get stuck between parallel objects. Instead, its ability to move in arcs allows it to essentially wiggle its way free.”
In a community that largely focuses on robots becoming smarter and more human-like, this ‘brainless’ robot brings a new perspective to the field of robotics, opening up discussions on the idea that brains in robots are, perhaps, optional.
For now, the ‘brainless’ soft robot is currently in discussion on how it can help promote more green energy. “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,” Yin says.
