A team of US researchers has developed a soft robotic gripper that can pick up individual droplets of liquid as if they’re solids.
Soft robots – made from malleable materials – can manipulate things gently, meaning they can undertake tasks their hard counterparts and even people can’t manage.
These lightweight robotic grippers, described in a paper in Materials Horizons, are fitted with an artificial electronic muscle, allowing them to do delicate work with 100 times the strength of human muscle.
“A single gripper as large as my finger is one or two grams, including the artificial muscle embedded. And it’s inexpensive – just one or two dollars,” says co-first author Dr Jiefeng Sun, a postdoctoral fellow in the Department of Mechanical Engineering at Colorado State University, US.
The grippers are coated with a “superomniphobic” substance: a material that repels almost all other substances.
This means that it’s extremely difficult to get the grippers wet, so they can interact with almost any liquid as if it’s a flexible solid. Droplets won’t break up and disperse on the grippers’ surface.
According to the researchers, these grippers could be used to clean up toxic liquid spills. They could also be useful for handling potentially infectious substances, such as those found in hospitals.
In their paper, the researchers demonstrate that the grippers could manipulate blood, among other liquids.
Because they’re so small and cheap, the researchers suggest that the grippers could be disposed of once they’ve picked up the droplets they’re after.
“It’s a first, but it’s also a very unusual example of a high tech product that is not terribly expensive,” says co-author Dr Jianguo Zhao, an associate professor of mechanical engineering and director of the Adaptive Robotics Laboratory at Colorado State University.