Scientists have created a shape-shifting humanoid robot

Scientists have revolutionized robotics: A shape-shifting robot can switch between liquid and metallic states to navigate complex environments without sacrificing durability. Because they can be both soft and tough, tiny sea cucumber-inspired robots can overcome the limitations of robots that are only one or the other, and thus have greater potential for use in areas such as electronics assembly and even application in medicine.

The researchers forced the robots to overcome obstacle courses, lift or deliver objects to a human stomach model, and even liquefy to exit the cage before returning to their original humanoid form.

“Giving robots the ability to switch between liquid and solid states gives them more functionality,” says engineer Chengfeng Pan of the Chinese University of Hong Kong in China.

From precision repair work to targeted drug delivery, there are many potential applications for tiny robots that can navigate places too small or confusing for humans to operate with typical vehicles. But hard materials aren’t the best for navigating tight spaces or tight corners; softer, more flexible robots are flimsy and more difficult to control.

To find a compromise, a research team led by Pan and colleague Qinyuan Wang of Sun Yat-sen University in China took inspiration from nature. Animals like sea cucumbers can change the stiffness of their tissues to increase load capacity and limit physical damage, while octopuses can change the stiffness of their arms for camouflage, object manipulation and movement.

To make a robot that could do something like this, the researchers needed a non-toxic material that could easily switch between soft and hard states at room temperature. They turned to gallium, a soft metal with a melting point of 29.76 degrees Celsius (85.57 degrees Fahrenheit) at standard pressure—just a few degrees below the average human body temperature. You can melt gallium simply by holding it in your hand.

The researchers embedded a gallium matrix with magnetic particles, creating what they call a “solid-liquid magneto-active phase transition machine.”

“Magnetic particles play two roles here,” says mechanical engineer Carmel Majidi of Carnegie Mellon University, one of the team’s senior authors on the paper.

“First, they sensitize the material to a changing magnetic field, so you can heat the material inductively and cause a phase change. But the magnetic particles also give the robots mobility and the ability to move in response to changing magnetic fields.”

After the researchers tested whether the solid-to-liquid transition was reversible (and it was), they put their little robot through a series of tests. Robots can jump over small ditches, climb over obstacles, and even separate to perform collaborative tasks by moving objects before they recombine and resolidify.

There was even a small version of the humanoid, shaped like a Lego figure, that melted to break out of a tiny prison cell, leaked through the bars, and was reshaped on the other side in a scene from Terminator 2.

The team then explored practical applications. They created a model of the human stomach and had the robot swallow and remove a small object inside (for example, consider a useful way to retrieve swallowed batteries), and then do the reverse, delivering the object the team had hoped for. can deliver drugs

To repair circuits, robots can go to the circuits and melt over the circuits to act as a conductor and solder; and even act as a fastener, seeping into threaded screw slots and solidifying to act as a screw without someone having to lock it in place. For real applications, the phase transition machine needs certain settings. For example, since the human body’s melting point is higher than pure gallium, a robot designed for biomedical purposes could have a gallium-based alloy matrix that would raise its melting point while maintaining functionality.

Researchers say this has not yet been studied in detail.

“Future work should continue to explore how these robots can be used in a biomedical context,” says Majidi. “What we’re showing is just a one-off demonstration, a proof of concept, but much more research will be required to understand how this could actually be used to deliver drugs or remove foreign bodies.” Source