Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: malex on May 14, 2009, 06:06:06 PM

Title: Sensing colour at a distance
Post by: malex on May 14, 2009, 06:06:06 PM

I'm trying to build a bot that can detect walls at a distance and turn accordingly.  The catch is that the walls are actually orange pylons and not a solid surface.  I understand the logic on how to implement a system to detect how far an object is, however I'm not too sure how to start detecting the colour orange at a distance (a meter or two would be sufficient I think...).

Can anyone point me to some hints?  I've read the guides on the site and they seem to only cover short distance colour detection.

Title: Re: Sensing colour at a distance
Post by: galannthegreat on May 14, 2009, 06:10:49 PM

Use a Sharp IR sensor with the camera. More specifically something like this would work:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=425-2062-ND (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=425-2062-ND)

Title: Re: Sensing colour at a distance
Post by: sonictj on May 15, 2009, 04:22:59 AM

Quote

The catch is that the walls are actually orange pylons and not a solid surface

if there are holes/discontinuities in the wall I would suggest using sonar rather than ir.  Sharp ir's have a narrow beam of detection.  As Admin says these sensors are susceptible to thin obstacles such as chair legs.  I would also recommend using a camera for the color detection.