You have just got to check out this cool watch application! Wristwatch components are to be used to capture energy from a beating heart to drive its own pacemaker. This is such an interesting story I thought it a must to tell you more about it! Current technology pacemakers are powered by tiny batteries. These last a little longer than 2 years and so require their batteries to be changed out every 2 years. This causes a requirement for an operation (albeit relatively common one) on an otherwise healthy or at least stable patient. Naturally any operation, especially one accessing the heart carries with it associated risks of infection and other serious issues.
There is an amazing new proposal to drive a pacemaker from components similar to those in a classic momentum spring winding style Swiss wrist watch. Swiss watchmakers have been involved in developing the prototype. Researchers at Bern Hospital University came up with the idea but didn’t have the technical capability to build a prototype. They were sensible and contacted Swiss watch makers, who jumped at the chance to collaborate with the university researchers.
The idea is simple and one wonders why nobody had thought of developing this idea before. This is often how great new inventions appear after you hear about them. The idea is that the mechanics for motion winding a classic Swiss watch would also be able to generate enough electricity from the vibration and motion of a heartbeat to generate the very small amount of electricity to power a pacemaker.
Once you have the power coming into the mechanical device in the form of shaking or motion from the heartbeat you probably want to store that in the battery so that you always maintain a minimum power supply for moments when insufficient power is generated from the heart.
Think about the amount of effort it takes to wind a good quality Swiss watch for example. You take the pin between your fingers and roll it gently for a few moments. That energy is stored in the watch spring and that energy is returned to the watch over 24 hours. Similarly I can see that the heart muscle requires a large amount of energy to contract but a relatively small amount of energy to signal to the heart.
Another Cool Watch Application
Another invention comes to mind, that is the invention powering radios in isolated locations in Africa. The clockwork radio.
This English invention allows people to wind a crank attached to an enlarged clockwork-like mechanism built into a radio. They wind it for several minutes (a relatively large amount of energy) which provides enough energy to a spring which stores it to play the radio for long period of time, up to several hours. This is possible because the electrical signals necessary to play the radio requires only a small amount of electricity. You can see some parallels here too. So a heartbeat from the heart muscle provides quite a large amount of mechanical energy whereas the actual neural signal to tell the heart muscle when to contract requires only a very small amount of electricity (explained more below).
Another example at an even smaller energy use end of the scale is a Wi-Fi speaker and smartphone. An extremely small amount of energy in the form of a Wi-Fi signal is required to transmit the information to the Wi-Fi speaker device. Incidentally see this link for more information on smart phones. In regard to the Wi-Fi speaker a relatively larger amount of energy is required to power the speakers and so all Wi-Fi speakers must carry their own power supply normally in the form of batteries or perhaps with a power supply cable of their own.
Similarly the heart muscle has its large energy supplies stored within it; within the muscles in the form of chemical energy which one feeds of course via the bloodstream which comes from the food one eats. The brain, analogous to the Wi-Fi signal, provides just a very small low energy signal to tell the heart to contract and when to do so. The pacemaker of course is normally required in a patient who has trouble regulating the signal to tell the heart when to beat.
Note that that this is only at the first prototype stage of the research.
How do you Fund such Research?
Who do we have to thank for the development of this idea? This cool watch application was developed and financially supported by the research funds of the Department of Cardiology, Bern University Hospital, Bern, Switzerland, the Swiss Heart Foundation, and the Department of Cardiology, Bürgerspital Solothurn, Solothurn, Switzerland.
So there you go that is how a small amount of energy recovered from the large energy relatively large energy mechanical energy coming from the heartbeat can be used to charge a battery and supply the relatively tiny signal needed to regulate the heart in the pacemaker. You can read more about this cool watch application by going to the Berne University Hospital article abstract here, which also names the experts involved.