Comments on: Automatic Color Detection

By: KLOZ

KLOZ — Sat, 12 May 2007 05:19:13 +0000

The main factor with speed is the time it takes for the LDR to reach a stable resistance. In my project this is about 1/4 second. It could be less, I never made mesurments. just figured leaving it at 1/4 would be safe. And Yes I could have used multiple LDR’s with COlor filters, but the main problem with that would be the fact that I would need more then one ADC chip, at $4 a pop that would throw off my cost savings. And not to mention using more of my 32 pins on my Propeller board.

By: Colin Karpfinger

Colin Karpfinger — Fri, 11 May 2007 06:31:22 +0000

thats an interesting way to do it, with diff colored LEDs and photo resistor.

Whats the limiting factor of speed? I would guess the mechanics, but I can’t be sure.

By: Tony

Tony — Thu, 10 May 2007 23:05:11 +0000

so this thing actually takes about 4 and a half minutes to completely sort a bag of M&M’s ? the one in my class only takes about 2 minutes to sort 2 (measured) cups of colored erasers.

By: Airton

Airton — Thu, 10 May 2007 15:19:16 +0000

You don’t need to assume that is a foto resistor. The correct name is light dependent resistor or LDR as you can see in any databook

By: bender386

bender386 — Thu, 10 May 2007 13:07:53 +0000

you can do it backwards with 1 white led and some LDRs with coloured filters on them.

and is photo resistor another name for light dependent resistor or are you thinking of something different because they are LDRs

By: Graham

Graham — Thu, 10 May 2007 11:53:54 +0000

“light dependent resistor (I’m assuming he means a photo resistor)”

I think he meant light dependent resistor, LDR an established term.

By: n3rrd

n3rrd — Thu, 10 May 2007 06:07:53 +0000

The video is running 4.5x faster than real life, sl.

By: Wolfmankurd

Wolfmankurd — Thu, 10 May 2007 02:51:39 +0000

I thought the 4.5x means it’s been sped up 4.5 times?

By: Tony

Tony — Wed, 09 May 2007 22:52:41 +0000

will o\\\’brian, i wonder if i get a sticker for seeing that one lol. nice job by the way looking forward to doing this pretty soon as my final for electronics class.

By: SL

SL — Wed, 09 May 2007 22:19:11 +0000

damnit, I noticed that before the change, too, but I thought ‘meh, he means LEDs’…

aw.

neat hack though — I’m amazed at how fast the thing is. Seems that he indexed the carrier to the right edge of the track, since if you look closely it returns all the way to the edge before moving out to deposit an M&M. If he figured out how to use relative positioning, it could be even faster…
though then you might get some cumulative errors.

By: Will O\\\\\\\'Brien

Will O\\\\\\\'Brien — Wed, 09 May 2007 18:20:13 +0000

Doh, Erik doesn’t since he didn’t use a valid email address.

By: akmixdown

akmixdown — Wed, 09 May 2007 15:44:01 +0000

I don’t know about you but I can make coloured resistors… it just depends on what shade of brown you want and how much current you’re willing to send through them. :-)

By: TheBlunderbuss

TheBlunderbuss — Wed, 09 May 2007 10:01:29 +0000

finally some color images on hackaday ! and look! capital letters!
:)

By: mrasmus

mrasmus — Wed, 09 May 2007 08:27:56 +0000

Several colored LED’s, I’m assuming you mean? Colored resistors :P.

By: Klintor

Klintor — Wed, 09 May 2007 08:24:35 +0000

I did this YEARS ago with a lego mindstorms kit. Easy Peasy.