AGV Need help.

Most people use ultrasonic rangefinding for detecting obstacles. It's pretty simple to implement, you switch the transmitter using the computer and have an amplifier to tell the computer when a signal is recieved by the narrow-band reciever.

You can do some dead-reckoning with acceleration sensor chips. I suppose this could compensate for slip in turns.

There's loads of ways to program obstacle avoidance, depends what it's purpose is really. Is it trying to reach some target by going round obstacles? Could just get it to turn left whenever it hits something.

Dear Deepak Rajput:

Many factories use wires embedded in the factory floor. The wires have a carrier frequency applied to them. The robot is instructed to keep the selected frequency between its sensors. Collision avoidance in that case is simply stop-and-wait.

Any kind of a coil. For your project, you might only need one wire. Amplify the signal received, and compare it with an opamp. If the differential voltage goes high "+", turn left proportional to the difference. If the differential voltage goes high "-", turn right proportional to the difference. If either sensor produces a zero output, stop.

As of obstruction detection, you could simply use a diffuse infrared emitter/detector. They are not expensive, probably suitable for a project of this nature. They do not work well in detecting roving mirrors or polished metal surfaces, or snow for some reason (looks white to me!). Other than that, they are pretty good. "Banner" is a good brand.

David A. Smith