An elastomer foam could lead to a change of heartAn elastomer foam could lead to a change of heart

A lightweight, highly stretchable elastomer foam with connected pores through which fluids can be pumped has been developed by researchers at Cornell University (Ithaca, NY). Using additive manufacturing (aka 3D printing) techniques, they have fabricated a machine that pumps like a human heart. The material also has potential applications in prosthetics and soft robotics.

The carbon fiber-silicone material is a "lot like a memory-foam mattress in the way it feels," explains Rob Shepherd, Assistant Professor of mechanical and aerospace engineering in a video interview posted on the university website. "We pattern it using additive manufacturing to make a machine that pumps like a human heart. We can make [the artificial heart] easily and quickly, and can even tailor it to individuals," says Shepherd.

When air or liquid is pumped through the pores of the device, the material can stretch by more than 600% beyond its initial length, says Shepherd. "And we don't have to use a lot of pressure to get the fluid to move through the pores," he adds, noting that this material was chosen because of its "potential to get FDA approval."

The researchers use a 3D printer to fabricate the mold into which the the material is cast using a "low-cost process for multiple design iterations," says Shepherd.

Although the regulatory pathway is long and arduous and it will be many years before this technology finds its way into medical applications, Cornell researchers say that they are pretty far along in making a prosthetic hand using this material and process. They are also working closely with medical practitioners, says Shepherd, "who are familiar with turning these devices into useful medical parts."

Shepherd is the senior author of a paper published in the journal Advanced Materials, which explores the effect of porosity on the actuator. "But now we would like to make the foam actuators faster and with higher strength, so we can apply more force. We are also focusing on biocompatibility," says Shepherd.