In science fiction films, robots are typically formidable and unbreakable. A recent innovation by Chinese scientists -- a flexible robotic hand -- is changing this rigid perception.

In a captivating demonstration video, two quivering black silicone strips, resembling soft chopsticks, were manipulated with magnetic precision to gently clamp and transport a fragile dandelion puff with utmost care and delicacy.

This is the soft gripper (PMSG) crafted by a team from University of Science and Technology of China (USTC), which integrates a porous structure into a magnetic silicone elastomer.

With some modifications, this machine manipulator is versatile enough to be employed in a range of applications, from in-vitro fertilization to wildlife rescue, according to the researchers.

POROUS STRUCTURE

Rigid robotic metal "fingers," which are designed to be both strong and precise, tend to be overly forceful when trying to manipulate anything fragile. Handling soft living objects, however, demands a delicate balance of shape adaptability and gripping force -- qualities that are often at odds with each other.

In engineering, incorporating more magnetic particles can boost the gripper's clutching power, but this augmentation often leads to increased rigidity, which in turn hinders its ability of adapting to objects of different shapes.

The USTC team's novel approach, however, utilizes a pore-forming agent that, upon heating, decomposes to generate countless tiny pores. This method ensures a high concentration of magnetic particles and simultaneously bestow the gripper with exceptional softness.

The intricate internal pores effectively absorb the shock energy from rapid grasping motions, reducing the risk of damage to fragile objects, according to the results published in the journal Advanced Materials.

Additionally, the porous surface structure increases friction, which in turn improves the grip stability and reliability.

In the laboratory, this gripper successfully picked up a slippery live goldfish and a shell-less raw quail egg.

In a small magnetic field, this gripper's lifting ratio can reach 30, meaning it can lift objects that are 30 times heavier than itself, said Li Mujun, a professor from USTC and lead author of the paper.

"Considering its pinching method, this gripper's performance is impressive, though it doesn't quite match the gripping power of octopus-like wrapping techniques," Li told Xinhua.

MULTIPLE SCENARIOS

In the future, this soft robotic gripper is poised to enable medical researchers and clinicians to delicately and noninvasively handle fine cell samples.

The applications include the collection of oocytes, sperm and other reproductive cells, as well as tissues from human organs, spanning across multiple medical domains such as reproductive research, clinical procedures, drug screening, the development of genetic disease models and regenerative medicine, said Li.

The magnetic gripper's remote-operability is a significant benefit, especially when it comes to integrating with mobile platforms. Its integration with mobile robots, for example, enables the gentle and precise handling of chicks, showcasing a versatility in delicate tasks.

Its compatibility with drones allows for the efficient capture of small fish from bodies of water and the subsequent swift, secure transportation across extensive distances, said Li.

This capability positions the gripper as a potential tool for both field sampling in natural environments and for the rescue of small animals, he added.