Video: See how the foam heart pumps liquid

A heart of foam could replace your own. Researchers inspired by soft robots have built a pumping artificial heart that could one day replace the real deal.

Recent years have seen the development of soft robots that mimic snakes and tentacles. They are made from flexible plastic and powered by compressed air that makes the bots flex and move.

But the network of tubes required to deliver air limits most of these bots to simple, flat shapes, says Robert Shepherd of Cornell University in Ithaca, New York. That’s why his team build their robots out of a solid, porous plastic foam, which naturally has an interconnected network of tubes to let air flow – just as our muscles are permeated by blood vessels. A solid coating of plastic seals everything inside like a skin.


The team tested the material with a few simple bending and extending devices that move when filled with air, then constructed a simple model of the human heart. It only has two chambers – as opposed to our four – but powering the heart with air makes it flex and pump water between them. But the foam heart doesn’t visibly beat on the outside because the plastic skin means all the expansion happens internally.

“It shows the three-dimensional complexity we can get from our process, but also we believe it has the potential, after further development, to be a viable replacement for a heart,” says Shepherd. Existing artificial hearts have multiple moving parts, which increases the chance of failure, but this new device is just a single piece of material.

Journal reference: Advanced Materials DOI: 10.1002/adma.201503464