In a groundbreaking study, a team of researchers has pushed the boundaries of soft robot technology by creating a “brainless” soft robot capable of maneuvering through complex and dynamic environments without human or computer direction. Published in the journal Science Advances, the paper titled “Physically Intelligent Autonomous Soft Robotic Maze Escaper” presents the latest advancements in soft robot design. This innovative approach utilizes physical intelligence, where the behavior of the robot is governed by its structural design and the properties of the materials it is made of, rather than relying on external guidance.
The research team’s earlier work focused on developing a soft robot that could navigate a basic obstacle course by twisting and turning its way through. However, this initial design had limitations, as it relied on encountering obstacles to change direction. Consequently, the robot sometimes became trapped between parallel obstacles, unable to progress further.
Building upon their previous achievements, the researchers have now introduced a new soft robot that can overcome more intricate challenges. Unlike its predecessor, this robot is capable of independent turning, allowing it to navigate complex mazes effortlessly. The key to its success lies in physical intelligence rather than computer guidance.
The new soft robot, like its previous iteration, consists of ribbon-like liquid crystal elastomers. When placed on a surface heated to at least 55°C (131°F) – hotter than the ambient air – the portion of the ribbon in contact with the surface contracts, inducing rolling motion. The speed of the robot’s rolling depends on the temperature of the surface.
However, a major departure from the previous design is the asymmetrical structure of the new robot. One half of the robot resembles a twisted ribbon that extends in a straight line, while the other half takes the form of a tightly twisted ribbon that also spirals like a staircase. This asymmetry leads to an imbalance in the force exerted by each end of the robot on the ground.
The concept behind the new robot is elegantly simple: due to its asymmetrical design, it can turn without making contact with objects or obstacles in its environment. To illustrate this principle, consider the movement of a plastic cup with a wider mouth than base. When rolled across a table, it follows an arc instead of a straight line, thanks to its asymmetrical shape.
The asymmetrical soft robot operates on the same principle. While it does change direction upon contact with an object, allowing it to navigate mazes effectively, it never becomes trapped between parallel obstacles. Instead, its ability to move in arcs enables it to wriggle its way to freedom.
The researchers conducted extensive testing to assess the capabilities of the asymmetrical soft robot design. They evaluated its performance in navigating complex mazes, including mazes with moving walls, and assessed its ability to fit through spaces narrower than its body size. The experiments took place on both a metal surface and in sand, showcasing the adaptability and versatility of the robot.
The breakthrough is not only significant for soft robot design but also opens avenues for applications where these robots can harvest heat energy from their environment. This new leap forward in soft robot technology provides a foundation for further innovative approaches to designing robots that can operate autonomously and efficiently.
The development of a brainless soft robot capable of navigating complex mazes using physical intelligence represents a remarkable achievement in the field. By leveraging an asymmetrical design, this robot can overcome obstacles and adapt to its environment without external guidance. As research in soft robotics continues to progress, the potential for real-world applications and advancements in autonomous robot design becomes increasingly exciting.