Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Arislan on October 18, 2006, 05:36:13 PM

Title: Colour sensor?
Post by: Arislan 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.
Title: Re: Colour sensor?
Post by: JesseWelling 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.....
Title: Re: Colour sensor?
Post by: JesseWelling on October 18, 2006, 06:14:21 PM
http://www.taosinc.com/
Just found this here : http://www.societyofrobots.com/robot_parts_list_sensors.shtml
Title: Re: Colour sensor?
Post by: dunk 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.
Title: Re: Colour sensor?
Post by: Arislan 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.
Title: Re: Colour sensor?
Post by: Admin 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.