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shobhan03
07-11-2010, 01:53 PM
hello there,
i am in search for colour sensors that have the maximum possible range of detection of colours. whats the maximum range a colour sensor can sense the colour..? could you give me some links or possible names of them to buy.?
thanks in advance.

vikas
07-11-2010, 05:10 PM
Use a camera ...

shobhan03
07-11-2010, 05:43 PM
Use a camera ...


yeah but how will it work fast..? i need to identify the the color quick too in least possible time. wouldnt a camera take time ?

vikas
07-11-2010, 06:07 PM
High speed Cameras can capture a Bullet in motion ... your application requires higher speed ?

MohitM
07-11-2010, 07:53 PM
A cheapo colour sensor could be made out of photosensors/LDRs and glass filters of the colour of your interest. Place a colour filter over a sensor to get a colour channel pair. The photosensor responds only to the light of the colour of its filter. Of course, the response curve depends on how good or bad your filters are.

In fact, this is how digital cameras work. Do a search on "Bayer filter". The wikipedia article is good. (http://en.wikipedia.org/wiki/Bayer_filter)

allbits
07-11-2010, 10:56 PM
what speeds are we looking at??
What range are we looking at??
Whats the size of the object we are looking at??

your definition of maximum possible range could be 100m, mine could be 10m, somebody elses could be 1Km.
It will save a lot of time for you and people at RI if you can give more details.

shobhan03
07-11-2010, 11:11 PM
what speeds are we looking at??
What range are we looking at??
Whats the size of the object we are looking at??

your definition of maximum possible range could be 100m, mine could be 10m, somebody elses could be 1Km.
It will save a lot of time for you and people at RI if you can give more details.


now thats good point you asked. the range is 1 to 1.2 m . primarily i have to distiguish between black and white colours..the sensor is not stationary,it will be on the bot.

shobhan03
07-11-2010, 11:17 PM
High speed Cameras can capture a Bullet in motion ... your application requires higher speed ?

not as high speed as the bullet. i wish to put the sensor/camera on the bot ,hence it wouldnt be stationary.

vikas
07-12-2010, 12:53 AM
Just use a directed infrared transmission , white will reflect ( ull have signal ) , black will not ... Will be very and very simple.

Is it for a competition then post a link , might suggest a better approach.

shobhan03
07-12-2010, 06:13 PM
Just use a directed infrared transmission , white will reflect ( ull have signal ) , black will not ... Will be very and very simple.

Is it for a competition then post a link , might suggest a better approach.

ok this seems good. so how about this plan now, i can have one transmitter on the bot which transmits directed IR ray, the ray get reflected when the objected with white or black is found and the recvr which is also to be placed on the bot detects it and accordingly the signal is processed by the micro-processor. but i think there has to be some angle or else the reflected IR ray would coincide with the transmitting one..?

adith
09-01-2010, 03:50 AM
Colour sensors are available at Roland electronics in hyderabad Part no being Sharp Make PD153 and Taos make TCS230