What could we use a battery free, self charging Freevolt for?


There is a new technology that uses the wifi, bluetooth, or other radio signals around us to provide power for small devices. It is called Freevolt. What could we do with this?

One idea is to marry it with an acid gas sensor in the Glowforge to alert us to the presence of hydrochloric acid, hydrogen cyanide, etc that might be generated from bad glues and other materials. Combine it with a graphene based supercapacitor for more power.



Interesting physics, very small amount of power…but developing. Thanks for posting that. - Rich


So how much power are we really talking here. They said they’re using it to power a camera and some sensors. Would we be able to pull enough to make, say, a sloth like robot that wouldn’t be able to move terribly fast but which would be able to run indefinitely wandering about sipping RF signals for juice? I can think of a lot of things that you could do with this kind of tech


The amount of power depends on the RF density. Cities are usually RF dense environments, but have dead zones too. For instance a house or business with Wi-Fi would be ideal. Lots of opportunities for low power electronics. - Rich


I have an old project on the back burner waiting for the enabling technology to come to life and this could be it. I call it the CCD Chirper, or Cricket for short. It would be a a security system that is powered by radio waves or movement next to it and send a CCD camera compressed signal to a facility to alert security of an intruder. It would also let out an audible chirp that would awaken and trigger other nearby sensors and together their pictures would capture the wider crime scene. Crickets go silent when disturbed and this would be sort of the reverse response.

They already have such things in intelligence circles that snap a picture when someone passes by and they look like a piece of rice. Bad sentence. The device looks like a piece of rice, not the people. lol


Yeah that seems like a good use for this. You could use capacitors to store up a little extra energy too which would increase the amount of things you could do with a cricket once it goes off, then it would charge itself back up waiting for the next perpetrator to wander by


As you might realize, the hard part is finding the low power chip that can send out the encoded data in a pulse of very narrow width. Pulse power can be quite high, even though the energy is very low. And then of course, there is the matter of developing the receiver capable of seeing these pulses.


Sensitive enough to sense the pulse and sophisticated enough not to be constantly tripping on the RF noise. Or you need to get your cricket to kick out enough of a signal to be easily identified over the noise. Any particular reason these would need to be wireless? Seems like some tiny embedded wired sensors could accomplish a similar task with high sensitivity and with the right wiring you’d have access to all the power you’d need


Good point. I thought some wireless devices would be useful outside to capture an escaping vehicle.


It would be a good application for a “tick” like device (to stick with the theme) that you could fire at a fleeing vehicle to tag it then get pings back as the device passes through dense RF fields. Wouldn’t need to be robust enough to send out GPS signals, just enough that with the right equipment you could zero in on where the little bugger was pinging from


For that matter, the chirp could be radio, not audible. The psychological effect on the perp to the sudden onslaught of chirps might be worth it.


That’s a great idea? Want to help me develop it? I could use all the help I can get. I also have been considering what drone technology might bring to the picture. Could we beam power to a drone supercapacitor to increase the drone’s range?


I thought of a slogan, “Chirp the Perp”.


Fair warning I’m a simple mechanical engineer, I know just enough about circuits and nano electronics to get myself in trouble. I’m always happy to throw my designing skills into a project though


The truest indicator of your value in any project, is your willingness to admit your limitations. Only then are you open to getting the best people for the task and letting them shine. Without knowing you, I perceive you as possessing real genius in this regard, as do many in this forum.


Falconers attach small radio devices to their raptors. If the bird fails to return, they use directional antenna equipment to find it again. The device will ping for days. - Rich


There are other devices that are seeking to gather energy from the warmth of the users hand to add some charge back into smart phones. - Rich


I have some experience with that type of thing, I volunteered for the Division of Wildlife a lot growing up doing field work with my parents. When they would take samples from deer or elk or bear we’d throw on a radio collar. Needed to be a lot bigger so the battery would work for a full year but that’s the idea, just something directional you could use to triangulate location would be plenty


Seriously, I view this forum as an opportunity to share new ideas, develop new concepts, and pursue collaborations of all kinds. If anyone thinks I can help in some way, I am here to listen to your vision.


This would be great for drones. The fancier ones have GPS, but if it is low on power or crashes into a thicket, this type or signal would be useful.