Reflective Tape Detecting Robot

[0506203]

I have to design a robot that can work its way through a maze made of a reflective foil tape on the floor. Does anyone have any suggestions of methods of detecting the tape so that the robot doesnt cross the walls. Trying to find info about designing an IR photo-reflective sensor but cant find much.

Cheers
Mark

 

[Krumlink]

Why not use a ultrabright White LED setup and some CDs Photocells on each side of the tape to follow it? Dont use foil tape, try white electricians tape.

 

[Sceadwian]

The single most important thing you need to do when designing a line following robot is shielding the sensor from the outside environment. IR, visible, or UV doesn't matter, you need to shield the sensor module. Use one light in the middle, and two sensors to either side.

When the left sensor exhibits a negative change to received light you need to turn right.
When the right sensor exhibits a negative change to received light you need to turn left.

Ideally you want an analog sensor and the ability to control the drive wheels in an analog manner so that it can react more slowly to slightly drifting off the line as opposed to completely losing it. Foil is relatively universally reflective, but the plain mat might not be so you need to determine the reflectance value of the mat and chose a color of light that the mat absorbs best. Use an RGB LED and filters over a series of light sensors and you could even chose which color line you follow.