Line follower lost line problem

[windozeuser]

I made a line following robot, but I need an idea on how to make it get back on the line when it "loses" the line and strays off the track. The problem I'm having is when the robot reads 0x00 from the sensors it means there is no line so it should stop the motor, but I have no idea on how to make it get back on the line.

The biggest problem is taking wide sharp turns and straying off the line by overshooting it

I was thinking of recording the last valid reading it was on the line, and make it do that until it finds the line, but it seems too "hackish"

Anybody with any ideas or experience in this area, I would appreciate your input

 

[upand_at_them]

You got the right idea, you have to keep track of what it was doing before it lost the line and them compensate to get back. Turning right and lost the line?...Make a hard left. Turning left and lost the line?...Make a hard right.

Here's a good resource: Wright Hobbies Robotics, line follower

 

[Mr RB]

Most of the competition line following robots have a number of sensors for each side, so instead of just 2 sensors they might have 6, ie 3 on each side extending outwards.

That allows them to still track the line even if the line is no longer on centre, so they can correct position without stopping and turning as the competition is often time based.