In a decision we completely agree with, these industrious young women decided that playing in the rain would only be more fun if it included an interactive light show. They wanted the rain itself to cause LEDs in their umbrella to light up. To achieve this, they put piezo sensors on each of the 8 panels of the umbrella. When that panel gets hit, its LEDs light up. You can see in the video after the break that it was quite effective.
Their next step should be to somehow increase the resolution to be similar to this one, while maintaining interactivity with the rain. How would you sense rain drops with more definition though?
[via Adafruit]
If you aren’t concerned about a precise one-to-one mapping of drop to LED, then use the piezo sensors to detect the sound of each drop hitting a rough area on the top and use it to trigger a random LED on the underside in the same area.
You wouldn’t get the point to point definition but you could get the hit rate accurate – and since no-one can really see the drops hitting the top it would have the same effect.
A bunch of these stuck on?
..’raindrops keep falling on my LED’…
Where’s the video?
I am so glad someone did this. I prototyped something quite similar for the arty category of the 555 contest, but didn’t bother to complete it full-scale with an umbrella.
You could use ALL sensors, and triangulate as many drops as possible. Obviously, you can’t do them all, the ones that fall at the same time. But if you can pick out individual drops, you can triangulate their location. Processor intensive though.
Rain? what’s that? Instead of singing in the rain, the wheat farmers will be crying the blues if there’s no timely rain soon. An out of the ordinary project to keep things from getting boring.