The idea of artificial muscles sounds like the future of medicine, with people getting new muscles built for them in a lab. But they may have applications beyond the human body. One you might not expect is absorbing shock and generating energy. That’s the idea behind a new project from engineers at the Fraunhofer Institute for Structural Durability and System Reliability LBF in Darmstadt. They’ve have developed a new elastic material that reacts to undesirable vibrations and dampens them more than previous technologies. The material uses electrical pulses to counter negative waves, like a muscle, which works better than the current method of using stretchy materials to passively absorb shock.
It works like this: alternating electrical current causes the material to rise or fall a few tenths of a centimeter upon command, several times a second. That oscillation can be timed to cancel out vibrations around the material. These materials could also produce power from that shock, say the researchers.
The uses for such materials could be wide. The researchers imagine using them in cars to reduce road noise from unwanted vibrations, but architects are also imagining using the materials in buildings. The ability to produce power would also be helpful in cities. "That would be of interest, for example, if you wanted to monitor inaccessible sites where there are vibrations but no power connections," said researcher Jan Hansmann in a press release. He cites an example: the temperature and vibration sensors that monitor bridges for their condition could harness the motion of the bridge itself to stay functioning without another power source.
Other materials that soak up energy from unlikely sources are in the research pipeline. Engineers at the University of Michigan are working on a heart-powered pacemaker to replace ones that require batteries (which have to be switched every 5 to 10 years). Their blueprint plans would create a new device that could generate 10 microwatts of power, which is about eight times the amount a pacemaker needs to operate. Elsewhere, engineers are using the motion of cars rumbling over a bridge to power sensors monitoring that bridge with electromagnetic harvesters. Researchers are also working on a harvester to suck up low-frequency vibrations from sources like humming machinery.