Hi ,
I'm beginner and i have a problem

I have to programme a robot who can follow black line.
When he lost black line he must turn left then right to find line.

I began to write program and it looks that:

task main()
{
while(true)

{

if (SensorValue(light) < 40)
{

motor[motorA] = 50;
motor[motorC] = 50;
}

else

{
if (SensorValue(light) > 50)

motor[motorA] = 40;
motor[motorC] = -40;
wait1Msec(250);
}
{
if (SensorValue(light) > 50)
motor[motorA] = -40;
motor[motorC] = 40;
wait1Msec(250);

}
{


if (SensorValue(light) > 50)
motor[motorA] = -40;
motor[motorC] = 40;
wait1Msec(250);
}

{
if (SensorValue(light) > 50)
motor[motorA] = 40;
motor[motorC] = -40;
wait1Msec(250);


}
}
}



And whats wrong?? Pealse for quick ask for ma question.

Here's an example of a line following program.



Try that first for the line tracking behavior. You should probably use a timer or an encoder (rotation sensor) in order to track how far it's gone.

In order to use a timer you must first clear it:



and then in a while loop:



Let me know if you have any more questions!

I`m was wrong express , the problem is that ,
robot must search black line in right and left.

I'm sorry, I don't think I understand. Do you want the robot to rotate left, then right, until it finds a black line? What do you want it to do after that?

I wont to do something like this
http://www.youtube.com/watch?v=JNprjLI7294

with the “sample program” it should work
Anyway, tomorrow I will work on a different approach to make robot trying to go straight on the line, instead of dancing on it.