super cool have seen alot of these pov projects popping up

That’s freakin’ awesome. If you could buy one premade with a dock for recharging and changing the text I’d definitely get one because I lack the skills to build one.

Would be really good for night clubs etc.

- Jussi

I know that there are many pov-projects going on and I do not claim the invention of “persistence of vision” for me. Not at least I posted the project in ladyadas forum so everybody can see where I got the basicstarttechnics from.

The difference to the other projects is the wish to make it availabel for the people that are not able or willing to solder / program and to give it a special use (communicating with unknown people). This will be clear in V.2 with usb- dockingstation to reload the built in li-ion battery and write txt on it very easy.

Posting #5 has a link to a keychain POV that you can spin to create messages in the air. They used an accelerometer to detect the velocity changes and thusly the resultant current velocity. This seems like overkill as increasing spin velocity could stretch a leaf spring. The springs end position could be detected with a variety of cheap methods (capacitance, light reflectivity, magnetic field) to determine velocity.

POV = Persistance of vision