The human hand is remarkably good at handling objects, from picking up a tiny needle to twisting a bottle cap.
Engineers have spent years trying to reproduce these abilities in robots, often by building complicated mechanical hands with joints, fingers and controls that resemble human anatomy.
Now, researchers have taken a very different approach. Instead of copying the shape and structure of the human hand, they created a much simpler robot that focuses on reproducing what a hand can actually do.
Called the BioflexBot, the new device can pinch, grasp, hook and rotate objects using a coiled spring, a flexible outer shell and a basic system powered by compressed air.
Despite its simple construction, it can perform some movements beyond the physical abilities of a human hand.
The research was published in Advanced Science.
Most robotic hands rely on numerous motors, joints, sensors and control systems. This can make them expensive and difficult to operate. The BioflexBot, in contrast, requires only two pneumatic inputs to produce a surprisingly wide range of movements.
Researchers tested the robot on several tasks designed to demonstrate basic hand functions.
For delicate pinching, the BioflexBot successfully handled an acupuncture needle. It was also able to operate a pipette to move liquid, showing that it could perform precise tasks that may be useful in laboratories or health care.
The robot also demonstrated impressive twisting ability. In experiments, it could rotate a bottle cap nearly four times farther than a human hand. It successfully hooked and lifted objects such as goggles and a toolbox.
Its grasping ability was even more unusual. The BioflexBot could securely hold objects of very different sizes, including objects nearly 13 times larger than those handled by comparable robotic systems.
One of its biggest advantages is its ability to change length. The robot can extend and contract about 3.5 times as much as a human hand. This extra reach could allow it to retrieve objects from confined spaces or work in areas that are difficult or dangerous for people to access.
The researchers demonstrated several possible real-world uses. The BioflexBot was used to inspect blades inside an aircraft engine, perform everyday tasks while attached to a humanoid robot and carry out parts of a chemistry experiment.
Its abilities come from what the researchers describe as structural and physical intelligence. Rather than relying on complicated electronic controls to manage every movement, the robot’s physical design naturally allows it to bend and adapt to different objects.
The researchers say this approach could provide high levels of flexibility and dexterity at a very low cost.
Future work will focus on turning the current prototype into a fully automated robotic system.
The BioflexBot also demonstrates a broader idea for robotics: machines do not necessarily need to look like humans to perform human tasks.
By copying function rather than anatomy, engineers may be able to build simpler, cheaper and sometimes even more capable robots.
