Looking for windscreen rain sensor design

[oldmp]

Windscreen Rain sensor

hi,

I need a circuit, which automaticly controlls the wipers of my car, when it rains. I searched with google, but i can't find any usefull information, just complet KIT's, such as HELLA Raintronic... It has got an optical sensor, for the windscreen, and wen some raindrops are falling on the screen, it controlls automaticly the wipers... I need something like that..

can someone help me?

How it works?

 

[aibelectronics]

Re: Windscreen Rain sensor

Your circuit I think is VERY easy. But sorry I have no schematics.
I think you'll need to do a lot of sleeves-rolling to get across this one. Inco-oporating the features of different circuits would do the trick.

Check discovercircuits and you'll see the schematic for a water seepage alarm. Your sensor circuit should be very close to this. Of course you wouldn't need the loud speaker.

The motor part is the easiest. Your sensor circuit forward-biases a transistor which in turn energises a relay, to connect the car battery to the wiper motor. And boom! your wipers start wiping.

Cheers!

 

[oldmp]

Re: Windscreen Rain sensor

hi,

The "water seepage alam" works with the conductive method. It needs 2 probes. If they are in water, it controlls something, what you want. But i need a schematic, with OPTICAL sensors.. So the rain sensor is inside the car, not outside the window...

 

[aibelectronics]

Re: Windscreen Rain sensor

umm... an optical sensor? To see the rain drops falling or what? I'm somehow lost. :?

 

[Borber]

Re: Windscreen Rain sensor

Look:
https://www.audi.co.nz/liveupdater/ArticleGlossary.asp?ArtID=838629129