DC motors problem

i found a simple schem of Line follower mobot using transistors.. the motors spin in the same direction(clockwise) when i build in Simulation..

Seems like i should work fine. Simulating, though might be tough.

The LDR resistance should matter somewhat. Normally they get smaller in resistance when hit with light and nearly open when dark. I'm thinking a CDS photoresistor, here.

When the beams are "balanced", the thing should travel in a straight line.

A darker surface will make one motor turn slower, thus turning the unit.

Now, I have a problem. I don't know what the "line" is made of? reflective material? Are these cells at an angle?

I can envision a reflective tape with the sensors near the edges and mounted at an angle.

You say you put - to Vcc and + to the collector. Are you saying this - and + are indicated on the motor? or are you referring to the old "hook-up scheme". Because the dc motor should run at the same speed no matter which way it is hooked up.

If the motors are marked with _ and + then most likely they are designed with built in diodes?