Scientists have succeeded in creating a robot that can change form from solid to liquid and then turn solid again. The robot can perform various movements, from jumping, climbing, to melting itself to get out of the cage. His behavior at first glance reminds us of the T-1000 robot in the film franchise Terminator.
The shape and movement of the machine is controlled by a magnetic field, which is expected to contribute to the advancement of biomedical technology and engineering. The use of this robot in the future could be to deliver drugs directly to the location of the disease, facilitate the assembly of electrical circuits, or even become the beginning of the creation of a universal screw.
Soft robots have actually been around for a long time, but they still have weaknesses when compared to hard robots. This kind of robot is certainly not as strong and fast as a solid one. Soft robots are also not easy to control. But this time, an international team of scientists managed to overcome this shortcoming using a material made of metallic gallium embedded with tiny magnetic microparticles.
This material, known as a “magnetoactive phase transition material” (MPTM), uniquely combines the high mechanical strength, load capacity, and fast moving speed of the solid phase with the “excellent morphological adaptability (elongation, splitting, and coalescence) of liquid phase,” reads the study published in a journal Matter on Wednesday, January 25.
“The scientific community has been working on designing magnetically responsive robots and small-scale machines like this one for a long time,” said Carmel Majidi, head of the Soft Machines Lab at Carnegie Mellon University who is the senior author on the study. “Along with those efforts, my team has pioneered many techniques using liquid metals—such as gallium which has a very low melting point.”
“We tried to combine the two approaches, and who would have thought, something like this could be created,” he continued. “When we built this machine, our hope was that we could take advantage of gallium’s high electrical conductivity, as well as the metal’s ability to change shape. All of that is then combined with the magnetic response of the magnetic microparticle system.”
This robot has magnetic microparticles in its body, so it can react to magnetic fields. Majidi and colleagues at Sun Yat-sen University and Zhejiang University in China placed the robot in an alternating magnetic field so it could move until it melted when it heated up.
“From the basic principles of electromagnetism, we can know that metals will spontaneously be electrified when faced with an alternating magnetic field,” explained Majidi. “It’s the spontaneous electric current that heats the metal and causes it to melt.”
With this method, the MPTM robot created by the researchers can solder electrical circuits, turn into a universal screw, remove objects from the prosthetic stomach and overcome the obstacles presented to it.
Apart from delivering medicine, the MPTM robot also has the potential to help doctors remove dangerous objects from the human body. Its ability to change shape allows the robot to enter locations that are impossible for humans to reach.
