Newswise — Read this aloud and your inner ear, by itself, will be carrying out at least the equivalent of a billion floating-point operations per second, about the workload of a typical game console. But what's truly amazing is the ear's efficiency. Consuming about 50 watts, that game console throws off enough heat to bake a cookie, whereas the inner ear uses just 14 millionths of a watt and could run for 15 years on one AA battery. If engineers could borrow nature's tricks, maybe they could build faster, better and smaller devices that don't literally burn holes in our pockets, writes Rahul Sarpeshkar in the May 2006 issue of IEEE Spectrum magazine.
The idea, called neuromorphic engineering, has been around for 20 years, and the likely first application is bionics--the use of devices implanted into the nervous system to help the deaf, blind, paralyzed, and others. There are two reasons for this choice: the biological inspiration crosses over to the application, and the premium on energy efficiency is particularly important.
Sarpeshkar's laboratory has constructed a bionic ear that consumes a mere twentieth of the power today's devices do. That makes the bionic ear small enough and energy-efficient enough to be fully implanted in a patient's head together with a two-gram battery needing a wireless recharge only every two weeks. As the best batteries currently available can be recharged about 1000 times, this device is the first to permit 30-year operation without surgery to replace the battery, according to Sarpeshkar, an associate professor of electrical engineering at Massachusetts Institute of Technology.
RSS