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Motion detector controling LED Answered

I would like to know how to combine narrow width motion detector to control LED Say putting two sensors side by side and each controlling independent LEDs. Not sure how to go about it. Is there kits available that I can modify? Also, I thought about using IR but I dont want to break a beam rather I hope make something thats like any outdoor motion sensor light but in a small scale that can control each LEDs. Any leads? I got almost zero experience in electronics. Well, if you count elementary school elec class that I took but forgot everything about it. thank you

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jifjif (author)2007-10-18

Its nothing more than an art project actually. I want series of lights that move along with you as you pass by it.

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Goodhart (author)jifjif2007-10-19

Just don't wear it to an airport ! LOL *sigh*

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Patrick Pending (author)jifjif2007-10-18

I think the simplest way of achieving this would be, to use the shadow cast by a person walking by to trigger the LEDs. An LDR (light dependent resistor) circuit would probably be the simplest, you would probably run into problems if the ambient light level changed though. Cheers, Pat. Pending

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jifjif (author)Patrick Pending2007-10-18

thanks Pat is there a kit that could modify to achieve this that you know of?

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Patrick Pending (author)jifjif2007-10-18

You would need to replicate the circuit for each LED that you plan to use, so buying kits would be expensive. Try searching for "LDR circuit" you will get tons of links. Pat. Pending

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jifjif (author)Patrick Pending2007-10-18

gmoon, good suggestion i guess calibration would be an issue, the project it self is moving or near day light where the light changes also, thx again Pat, i will look in to that.

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gmoon (author)jifjif2007-10-18

Photo transistors at least have simple lenses, but not optical-quality ones. Maybe something as simple as a pinhole-type focusing element together with the phototrans?

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jifjif (author)gmoon2007-10-18

hmmm thats gonna be tough. Calibrating that would be difficult since i would need to find a lens in between photo transistor and pinhole. but i will give it a try. thanks again. will post progress if any

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gmoon (author)Patrick Pending2007-10-18

This approach uses a matrix of independent elements, and would be a very cool art project. The largest obstacle would be that each photo-sensitive cell would need a lens element. Photo transistors, CdS resistors, photo diodes, etc. measure incident light--light falling on the matrix itself. You want to measure light hitting objects 3-10 feet away. Each cell would not only need a lens, they would all need to be 'aimed' also, or the results would be fairly incoherent (some jumblyness would be cool, for the fx, tho.) Like the wood mirror, doing this in a darkened space, and providing your own illumination will help...

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jifjif (author)2007-10-18

any thoughts on using web cam and pixelating the image to convert them in individual light activator?

thats getting too complicated but i was thinking more like the "wood mirror"

http://www.smoothware.com/danny/woodenmirror.html

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Patrick Pending (author)jifjif2007-10-18

The "Wooden Mirror" is an amazing piece, but very complex. Cheers, Pat. Pending

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guyfrom7up (author)2007-10-18

what you want is ultrasonic stuff, you can buy some stuff for like 7 dollars. Don't try using IR LEDs, it doesn't work, I tried, It can only sense like an inch away.

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Goodhart (author)guyfrom7up2007-10-18

well, you can make them more sensitive, but then, if you wish to detect "bodies" up nearer, they could give an awful large amount of false positives. But then again, so do many motion detectors (I have a pair at home for security reasons that I don't use because they would go off every time an automobile went by the house with bright lights on....*sigh*

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Patrick Pending (author)2007-10-18

It would help a lot if you explained in more detail what you were trying to detect and why. Cheers, Pat. Pending

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