Author Topic: Colour sensor?  (Read 3831 times)

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Offline ArislanTopic starter

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Colour sensor?
« on: October 18, 2006, 05:36:13 PM »
http://www.lynxmotion.com/images/html/proj050.htm

I'm a bit confused by the above robot. Can someone explain how it can see colours? I don't see a camera attached to the robot.

Offline JesseWelling

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Re: Colour sensor?
« Reply #1 on: October 18, 2006, 05:52:53 PM »
I see that he has 3 trim pots and I'm guessing that's to tune the input from a wavelength specific photoresistor of some sort. maybe you could use celophane covered photoresistors....never really heard of it but.....

Offline JesseWelling

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Re: Colour sensor?
« Reply #2 on: October 18, 2006, 06:14:21 PM »

Offline dunk

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Re: Colour sensor?
« Reply #3 on: October 18, 2006, 08:06:57 PM »
if you have a look here: http://www.lynxmotion.com/images/jpg/color.jpg you will get the idea.
it is illuminating the m&m with different colours of light.
switch on the different colours of led, one at a time and
a red m&m will reflect back more red light,
a blue one will reflect back more blue light,
etc.

dunk.

Offline ArislanTopic starter

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Re: Colour sensor?
« Reply #4 on: October 19, 2006, 09:24:20 AM »
Thanks! I hadn't realised the meaning of "cds" on the schematic. This explains the meaning:
http://www.robotroom.com/ColorSensor.html

It looks like that researcher got a lot of good photoresistors for a bargain :S Unfortunately I moved to Brazil recently and nothing here is cheap.

Offline Admin

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Re: Colour sensor?
« Reply #5 on: October 19, 2006, 09:51:46 AM »
ive been thinkin of making a color sensor tutorial for awhile now . . . and not just for visible light . . .

what dunk said is the cheapest/easiest way . . .

the taos sensors are for only a single color, so you would need multiple of those designed for different colors . . . those are higher precision, meaning they work great for telling the difference between shades of colors.

 


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