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shubhamgautam
09-24-2008, 12:06 AM
On one micromouse site it was mentioned that AC coupling/Capacitor coupling along with synchronous detection can help us prevent the problem of ambient light.

Well i can understand the principle behind this method , but i have doubt that suppose i indeed do Ac coupling , then will by sensor be able to detect different background colors while following white line, bcos while detecting synchronously , we will only observe say a rising voltage or falling voltage(depending on circuit) , so white can be detected from black easily, but can white be detected from other background colors ie blue or red or green etc?

Also the timing between firing the IR transmitter and the time after which we should read the IR receiver will (i guess) decide how many colours we can detect.

In short I am not sure if this method will be quite sucessful in my case.
any comments plz!!

orion
09-26-2008, 12:03 AM
The ac coupling surely would enhance the performance...will clean up most of the dc noise (ambient light)

so white can be detected from black easily, but can white be detected from other background colors ie blue or red or green etc?
You can detect white line on black,green,blue surface but not red! Since u'll be using an IR transmitter, the red color will reflect back the IR to a great extent and would appear as good as white to the receiver.


Also the timing between firing the IR transmitter and the time after which we should read the IR receiver will (i guess) decide how many colours we can detect.
To detect colors, u'll need a completely different approach:
http://www.robotroom.com/ColorSensor.html

Hope this helps.
Regards,
Mohit