The robot can have a gentle hand!

One of the biggest problems with robots today is that their hands—the scientific name is the “gripper”—are too clumsy, often need to be changed according to different tasks, and it is difficult to be as delicate as a human hand.
Researchers at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland are working to change the above situation and are developing a soft, flexible electrostatic adsorption fixture that can pick up objects 1,000 times the weight and Gently pick up an egg or a piece of paper.

"We have developed a new type of robotic grip that can grab objects of almost any shape," said Herbert Shea of ​​the SpacePlus Laboratory at EPFL. "And it can capture not only fragile and fragile objects, but Can also lift heavy objects."

EPFL says the soft, flexible fixture combines a stretchable rubber electrode with electro-adhesion—an electrostatic force—technique: "It is expected to change robotics forever;" The project's personnel also include EPFL's Ph.D. candidate Jun Shintake.


Robotic fixtures using electrostatic adsorption technology can pick up eggs "softly" (Source: EPFL)

Dario Floreano of the EPFL's Laboratory of Intelligent Systems said: "We have integrated two previously studied functions - soft electrodes and electrostatic adsorption technology into a single device;" Shea envisions this fixture It can be used as a laboratory robot or companion robot. It can also be used in prosthetic or food industry production lines, even picking up debris in space.

The key element of this type of fixture is the electrostatic adsorption force, which allows the robot to firmly grasp the item with a soft "finger" without causing damage to the item due to too much force; this clip has two pairs of "finger" It's like using a thumb to hold something with another finger, and you can work with more than one finger—each finger is paired with a relative thumb.

The principle of electrostatic adsorption is to apply a voltage on the rubber finger of the fixture embedded with the conductive strip, so that the finger bends inward and adsorbs to the picked object like the human muscle; because the fingers are soft, they can be made It is attracted to the shape of an object to which static electricity is attached. Compared to the past, soft fixtures must know in advance the weight, shape and fragility of the items being grabbed.


The newly developed robotic fixture is like picking up a strawberry with a thumb and another opposite finger (Source: EPFL)

Each finger of the fixture has a five-layer structure, including a pre-stretched elastomer sandwiched between two layers of electrodes like a sandwich, and two outer layers of different thicknesses for the fingers to be energized. When stretching outwards when two layers of electrodes are energized, the two fingers grasp the middle item and are electrostatically clamped.