The thin, flexible pump can make the robot soft even softer

Soft-body robots move by selectively inflated or deflated pneumatic “muscles”. And although the muscles themselves may be soft and slightly flaccid, they are often connected to hard, fiddly pumps. However, a new pump is both small and versatile.

Developed by scientists at the University of Bristol, a 5-gram pneumatic electric pump is the size and shape of a credit card. Not only is it thin and bendable, it’s also cheap and easy to manufacture.

The test device is in the form of a flat bag, one side with an air tube attached. Clamped inside that bag is an air bag and a small amount of dielectric fluid. When an electric current is applied to the electrode plates on either side of the pocket (and thus on both sides of the liquid), a process known as dielectrophoretic liquid locking occurs.

As part of this process, two electrode plates compress the bag by being attracted to each other – they start on one side of the bag and move toward the other. This action causes the air in the bag to be squeezed out, passing through the tube and into an attached pneumatic mechanism, thereby expanding it. When the current is interrupted, the bag “decompresses” and opens, drawing air back from the contracting muscle.

By varying the voltage applied to the electrodes, you can control the intensity and extent of the movements triggered by the muscle.

It is hoped that once the technology is further developed, it could be used not only in robots but also in clothing to help physically difficult wearers move their arms or legs. .

An article on research led by Professor Jonathan Rossiter, has been recently published in the journal Robotics. The electric pneumatic pump is shown in the video below.

Source: University of Bristol