In an experiment that reminds the film saga TransformersPrinceton University Engineers They created a type of material that can expand, adopt new forms, move and follow electromagnetic orders such as a robot with a remote controlalthough it lacks engine or internal gears.
“A material can be transformed into a robot, and controls an external magnetic field,” said researcher Glaucio Paulino, leader of the study published in Nature. Paulino’s team was inspired by Origami’s art to create A structure that blurs the boundaries between robotics and materials. The invention is a metamaterial, a material designed to present new and unusual properties that depend on its physical structure and not on its chemical composition.
In this case, Paulino’s team built his metamaterial using a combination of simple plastics and Magnetic compounds made. Then, through a magnetic field, they modified the structure of the metamaterial, causing its expansion, movement and deformation in different directions, all remotely and without touching it.
“The electromagnetic fields transport power and signal simultaneously. Each behavior is very simple, but when combining them, the behavior can be very complex -adds Minjie Chen, co -author of the study -. This research has exceeded the limits of electronics of power by demonstrating that the torque can be transmitted remotely, instantaneously and remotely accurate to activate complex robotic movements. ”
The result is a modular set of numerous reconfigurable unit cells that are mirror images. This duplication, called chirality, Allows complex behaviors: such as contortions, turns, contractions and even shrink with a simple touch.
“The current work has achieved extremely versatile mechanical metamaterials by controlling the assembly and the chiral state of the modules -says the study -. versatility and potential functionality of the modular and chiral metamaterials of Origami are really impressive ”.
To see what this metabot was capable, which “would boost soft robotics, aerospace engineering, energy absorption and spontaneous thermoregulation” (according to the authors), it was used A laser lithography machine to create a 100 microns metabot prototype (a little faster than human hair). Thanks to him it was discovered that similar robots could one day manage medications to specific parts of the body or help surgeons to repair damaged bones or tissues.
Cen’s team also used the metamaterial to create a thermoregulator that works by alternating between a black surface that absorbs light and a reflective. In an experiment they exposed the metamaterial to intense sunlight and managed to adjust the surface temperature of 27 degrees Celsius at 70 ° C and vice versa. Another possible use lies in antennae applications, lenses and devices that process wavelengths of light.
The key to this metamaterial is geometry. The authors built plastic tubes with support struts arranged so that the tubes are twisted when compressed and compressed when twisting. In Origami, these tubes are called Kresling patterns. The researchers created the basic components of their design by connecting two kresling tubes, which are Specular images, on the base to form a long cylinder. As a result, one end of the cylinder folds when turning in one direction and the other when turning in the opposite direction.
This simple pattern of repetitive tubes It allows to move each section of the tube independently by means of accurately designed magnetic fields. The magnetic field makes the Kresling tubes twist, collapse or open, creating complex behaviors.
Paulino explained that a consequence of the chirality (the specular sections) is that the material can challenge the typical rules of action and reaction of physical objects. “Normally, if I turn a rubber beam in a schedule and then in an antihoran a metabot that collapses when turning in a schedule. The device is reopened by rotating it in an anti -Horary sense, which is normal behavior. However, if it turns in the opposite direction (in an anti -horo direction and then in a schedule), the same device collapses and then collapses even more ”.
This asymmetric behavior simulates a phenomenon called hysteresis, in which The response of a system to a stimulus depends on the change history within the system. These systems, present in engineering, physics and economy, are difficult to model mathematically.