When Amin Karami and Daniel Inman, aerospace engineering researchers at the University of Michigan, began to work with materials which generate power from physical stress, they weren’t looking for a medical breakthrough. They were, in an endeavor more directly appropriate to their profession, looking to design a light unmanned aircraft which could be powered by the vibrations of its own wings. But as they looked at the properties of certain power-generating piezoelectric materials, they determined that they might also have an application for powering pacemakers using the human heart’s own vibrations. If their research proves successful, this could eradicate the need for costly, stressful pacemaker battery replacement surgeries which must typically be conducted every five to ten years.
Standard Pacemaker, Image © flickr user Steve Winton
The research for a heart-powered pacemaker is still in its early stages, but the scientists describe the device as harvesting the heart’s vibrations through a hundredth-of-an-inch thin slice of piezoelectric ceramic material, which would “briefly expand” in response to the heartbeat. The material then converts this stress into voltage. In addition to the precisely carved ceramic plate, the researchers added magnets “whose additional force field can drastically boost the electric signal that results from the vibrations.”
U of M reports that the device could “could generate 10 microwatts of power, which is about eight times the amount a pacemaker needs to operate.” Additionally, the piezoelectric materials would remain responsive between a range of 7 to 700 beats per minute, continuing to function even if the heart is under severe stress.
Lead Image © flickr user Eric Schmuttenmaer