4 ms·
The example given in the article was a pacemaker. I'm guessing there _are_ applications where you don't need a lot of power, but you do want it over a long tim
by willvarfar 1y ago
The example given in the article was a pacemaker.
I'm guessing there _are_ applications where you don't need a lot of power, but you do want it over a long time and without needing to charge or replace batteries.
It's also easy to imagine places where, whilst power is available, there are manufacturing advantages in not needing to. For example it might make economic sense to have self-powered wirelessly-connected sensors on car bumpers just to avoid the manufacturing cost of wiring them all up?
- Am4TIfIsER0ppos 1y agoWireless sensors? I'm sure the engineers will see the ether works fine in a lab but as soon as you try it in the real world it vanishes.
- thebruce87m 1y agoWe already have wireless sensors in cars - tyre pressure monitors.
- crinkly 1y agoPacemakers need a hell of a lot of power for a short amount of time occasionally. To do that you need to store it in something which can be discharged quickly and is low impedance. Which is a capacitor. This thing generates so little power you couldn’t charge a capacitor up quickly enough or keep one charged with the leakage.
- burnt-resistor 1y agoYou're nothing thinking this through. It could trickle charge a capacitor or supercapacitor that has a very low self-discharge rate. There's a circuit called a Joule Thief that can extract usable power from very low voltage sources. There are other tricks to do voltage multiplication like using diodes and capacitors, but there are also micropower switching boost converters too.
- crinkly 1y agoYes I know this. I’m a qualified EE. Go do the numbers on a supercap with quoted leakage and a decent error margin.
- robin_reala 1y agoYou’re talking about an implantable defibrilator, not a pacemaker?
- crinkly 1y agoNo. The heart is relatively high impedance. You need a low impedance source to drive it even on a trivial basis.
- shakna 1y agoA lot of pacemakers on the market today are remote access. They can be dialled into by your doctor and adjusted, in concert with live alerts and logs. Thats not infintisimal power requirements. (Cellular is cheap, but not nothing.) Whilst we do have long lasting applications in places, a pacemaker was a poor choice of the article.
- Bluestein 1y agoI shudder at the hackability potential of these things ...