AGVs use a number of different navigational methods to move around the work place. The earliest AGVs followed a wire embedded in the floor. Nowadays it’s becoming increasingly popular to equip AGVs with laser target navigation systems. LGV, or laser guided vehicles, are computer-controlled vehicles that are used in material handling. These vehicles navigate by using laser transmitters and receivers on a rotating turret. They are especially popular for repetitive actions or for transporting extremely heavy loads.
There are two different types of lasers used for laser target navigation systems; modulated lasers and pulsed lasers. At first I thought the laser beam was visible, something similar to the laser pointers that are mounted on guns. However, I was sadly mistaken. The lasers on LGVs are actually invisible. These invisible lasers bounce off reflective tape placed on walls, poles or machines at the height of the laser. The LGV calculates its position by measuring errors between expected and received angle and distance measurements from the retroflectors.
Unlike the AGV in my previous post, LGVs can go in reverse. They aren’t burdened by a train of carts to restrict movement. Laser guided vehicles can come in many different types including, high reach lift, fork lift, conveyor-bed and reel LGVs. High lift LGVs are commonly used for transporting and stacking heavy pallets and can carry up to 1200 kg. The benefit of laser target navigation systems is the ease of which routes can be changed using a PC. This makes it easier to add more carts to the system and expand the work area.