Harish:

Have you done the lab work we asked you about 3 months ago?

How is the sensor pickup and detection stuff working?

Have you recalled the posting I made where in I showed that a 200 or even a 400 step stepper will be nearly useless for accurate angle measurement. See...

http://www.8052.com/forum/read.phtml?id=61439

I guess you purchased a PFD (see http://www.8052.com/forum/read.phtml?id=61706 ) you have apparently not drowned yet.

Have you yet figured out your third variable problem? Your scheme with two targets WILL NOT give you triangulaton. It will take 3 targets or some other fixing of the position of the vehicle in order to achieve position determination with just two targets. You were asked this detail over and over before and it is clear you still have no full concept of the problem.

You should be using a DC motor with a carefully regulated speed control as monitored by an encoder on the motor so that the motor is known to have a constant angular velocity. Then you need to mount two additional sensors on the vehicle itself to measure a known angular displacement for the laser assembly. A high resolution reference can then be attained using a timer to measure the motor displacement through the known angle. Using this you can achieve 16 to 20 bit or better resolution for your angle measurement. This is what you need to make a reasonable triangulation system. Plus work in that third target!!!

Michael Karas